Okay, all you armchair photographers...

Discussion in 'Film and Processing' started by James G. Dainis, Jul 7, 2004.

  1. James G. Dainis

    James G. Dainis Moderator

    ...take a look at this. For the following, I used Fuji NPH set at box 400 ISO. My incident light meter indicated an exposure setting of f11@1/250 sec. That is in keeping with the "sunny 16" rule as it was a slightly overcast day in Arecibo, Puerto Rico yet quite bright. The following photos were taken by laying the negative strip on a light box and using a digital camera. The prints were scanned on a flat bed scanner. No photoshopping was used except to resize the photos.
    [​IMG]
    The first frame (9) was the indicated exposure, f11, 1/250
    The second frame (10) was overexposed 5 stops f4, 1/60
    The third frame (11) was underexposed 3 stops f16, 1/1000
    The prints were made at a one hour WalMart Fuji Frontier. These are the results:
    [​IMG]
    Normal exposure
    [​IMG]
    5 stops overexposed
    [​IMG]
    3 stops underexposed
    The color from the scan seems to be a bit bluer than the actual photos in which the trees are true green. But, as I said, I made no corrections in photoshop. I was rather surprised at the results. They are not that bad.
     
  2. An amazing demonstration,thanks.One thing that helped you a lot in this example is the cloudy day.The exposure latitude of any film,varies with the brightness range of the subject.You can overexpose a subject with a short brightness range more than a subject with a long brightness range before loss of sharpness,excessive grain,and long printing times cause trouble.On a bright day,you can expect slightly different exposure latitude limits due to the effect of the longer brightness range.
     
  3. Excellent demonstration James.

    5 over + 3 under = 8 stops total range used.

    8 x 0.3 = 2.4 log E total latitude demonstrated in the film.

    6 x 0.3 = 1.8 log E normal working range of a scene.

    The film has excellent latitude and a long curve before you run into the toe and shoulder. Using that estimate, 2 stops of the over and under were on the straight line, and the rest was either on the toe or shoulder, or the film has an extended straight line.

    If the density of the negatives are represented at the correct density, the film is probably conservatively rated as well.

    It seems to me that is what you guesstimated in another post? I mentioned in the other thread that I had made exposures of 400 film at 1200 and 2400. That falls between your exposures and was done nearly 20 years ago, but it agrees in spirit with what you did. Fuji has a good film there. Wonder how EK would fare?

    Now, lets see Steve do a series 10 stops over and under.

    Ron Mowrey
     
  4. Remember too that scanners are pretty good with underexposed negs, may not be so lucky with optical enlarger with -3 underexposed neg. (?)
     
  5. Print film, particularly NPH, can take a brutal amount of over exposure. Fuji Reala and Portra NC can actually take more, and I've recovered VPS images shot 4-5 stops over exposed with only slight image loss. Note this was with conventional optical enlargers.

    The large brightness range in this scene negates over dramatizing the under exposure latttide of print film. If anything, it serves to demonstrate the auto histogram capabilited of the Frontier to extract good information from a thin neg. Try it with general photo work, or use a traditional lab, and the last image will take a beating. A conventional lab would likely handle the middle image better.
     
  6. An excellent demonstration. Especially useful for those who
    obsess over whether their camera handles 1/3 stop
    increments vs. 1/2 stop increments, or those who
    argue that their camera with twenty-three segment
    4-D matrix metering versus is so far superior to last
    year's model with only twenty-one segment 3-D metering. Also good for
    answering those who ask "I'm screwed -- I accidentally exposed
    Portra 400 at 320 -- what can I tell the lab to fix it?".
    <p>
    Of course, the results could be quite different for different types
    of film (particularly if you use slide film). The lab makes
    a difference, too, and I'm impressed by the Frontier lab's
    ability to pull detail out of the underexposed neg.
    <p>
    This was standard exercise I remember doing decades ago,
    with B&W film and a conventional darkroom. I think we
    bracketed in two-stop increments from four stops
    underexposed to six stops overexposed, and tried to
    get the best possible print of each. It's good for
    everyone to try something similar at least once,
    to get a feel for what overexposure or underexposure looks like
    and to get a feel for how precise one must be in measuring
    exposure.
     
  7. Your point is what ? That the film is a good film - indeed it is.
    The comment that the conventional lab would handle the second shot better than the other 2 shots - I cannot agree with - The automated equipment in the conventional lab is very sophisticated equipment, and so is the frontier - the fact is that it is in the scanner and image processing. To understand something about the conventional lab you must also understand the process on the equipment - a full roll negative goes through a high volume (20k prints/hr) machine. There exists a technology some call it order uniformity - whereby the machine compensates its corrections on an order basis for both color and density, there is also some machines that have frame level correction and then there is a third that allows for frame level and order level in increments for both color and density. In effect the technical people of the lab control this response. None of these frames would be difficult to produce on such equipment and achieve similar if not better results.
    By the way the color being a bit bluer from the scans - color Gamut is different on the monitor than the paper - you will never get a "True Match" - but if you scan and then print - the prints from your printer should match the print "in theorey" .. you will not be able to tell the difference - it all has to do with the color space.. if you work with Digital - use TIFF files.
     
  8. So, why would I should I rate print film at other than box speed? I never saw much point in rating 400 film at 320. Since I'm now using cameras that read the DX code, I'm more worried about manually setting the ASA for one speed film and then fogetting DX is off if I change film speeds/types.
     
  9. I recently had an opportunity for the same demonstration, tho' mine was through pure brain fart.

    My cousin wanted some photos of her 15-year-old daughter dolled up in a black dress for a school party. I was switching between cameras using the only color negative film I had handy, Kodak Gold 100 (pretty good stuff, really).

    All was well until I noticed that I'd underexposed several of the nicer poses by setting the aperture for the wrong reading on the flash, which was set to 400. With that black dress I figured there was no way we'd see any texture. The best we could hope for was that the minilab wouldn't make the prints too grainy.

    Well, the two-stop underexposed shots came out pretty well. Not unacceptably grainy (looked more like Kodak 400 than 100) and some texture was still visible in her black dress.

    Naturally the properly exposed photos killed. She's a criminally cute kid.

    Some color negative films can be very forgiving.
     
  10. "So, why would I should I rate print film at other than box speed?"

    To give yourself more underexposure protection. Let's take HD400 as an example. It's data sheet says, "Satisfactory negatives result from exposures 2 stops under to 3 stops over the correct exposure." If you set your camera to rate this film at a lower EV (and you let the camera decide the exposure) then you are effectively giving yourself 3 stops underexposure.

    In the typical "girlfriend standing under a tree with a clear sky in background" scene, it is my opinion that if you mindlessly use weighted average metering it is easier to underexpose the shadows than to overexpose the sky. When we see this picture, more relevant detail is lost in the shadows than is lost in the sky, so we decide the picture is poor. If we overexpose slightly we pick up a "zone" in the shadows. We usually don't care if we lose a "zone" in the sky in such a photo.
     
  11. I never said I could print 10 stops over,I said from a tone reproduction standpoint only that many more stops of over exposure are built in to most negative films.I then said that I had seen T-Max 400 developed to a contrast index of 0.60 that had almost 10 stops beyond the diffuse-highlight region where the straightline continues without forming a shoulder.I also mentioned that 3 stops of overexposure is a practical limit,or else grain and density cause printing troubles.I found its best not to use any more of a film's over exposure latitude than is needed for adequate shadow detail.
     
  12. Re. 3 stops underexposed - The Frontier's scanner and software have done a very
    good job at extracting shadow detail which frankly I can't even see on the negative
    (the trees, left hand corner). There is no way you could make a comparable print on
    an analog system.
     
  13. An excellent demonstration. Especially useful for those who obsess over whether their camera handles 1/3 stop increments vs. 1/2 stop increments.....


    But for transparency shooting, such stuff IS necessary.
     
  14. My standard exposure latitude test using this scene (should be labeled EI 6400) has about a 6 stop brightness range, depending on zoom or size of spotmeter, which might be why I got only -2 latitude for NPH. On overexposure I drew the line at +5 due to uncorrectable magentafication, which was less of a problem with UC400. Ken S, I agree with Scott Eaton that conventional labs have an easier time dealing with overly dense negatives, especially color correction thereof, than digital process. Note for instance that clouds in James's +5 shot are too warm. NPH magentafication I encountered was primarily in scans.
     
  15. EricM

    EricM Planet Eric

    Thanks for this effort James! However, as Bill said, it's not the scene I would have chosen for such test. But thanks all the same man. ...relaxing into my armchair now...
     
  16. Thanks for the demonstration, James. I am very surprised at those results. I never had the bad luck to over- or underexpose a film so dramatically, not even in the times before DX coding of film cassettes. Nevertheless, the result are far from disastrous!

    I always shoot colour print films at nominal speeds, measuring for the shadows, and am satisfied with the results. Only exception are low-contrast scenes, which I overexpose 0.5 - 1 stop. Old habit maybe, since the times of VPS.
     
  17. On July 3rd, Steve Levine said:

    "All of the Portra 400's can handle almost 10 stops of overexposure!"

    He promised to post pictures and added that with his series of over and underexposure, similar to James examples above, we couldn't tell the difference.

    Please go here: http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=008gt0

    for the entire exchange.

    I invite Steve to follow up on his promise.

    Thanks in advance Steve. Eric and I are looking forward to it. I'm sure James would like to see them as well.

    Now, I would like to add that there is a method by which the images of underexposed negatives can be catalytically enhanced to yield more information than what James has shown. This was the subject of the work I presented at a meeting of the International Congress of Photography. It would allow 3 - 5 stops or more of underexposure with results in imaging similar to a normal exposure. Of course, grain and sharpness would suffer. You don't get something for nothing. I have not tried this method in about 20 years, and it is kind of exotic, but if there is interest, I will describe it on the forum.

    In addition, if anyone is interested, I can draw and post hypothetical curves to show what took place in James negatives to yield such good results and to explain my math above.

    Ron Mowrey
     
  18. There exists a technology some call it order uniformity - whereby the machine compensates its corrections on an order basis for both color and density, there is also some machines that have frame level correction and then there is a third that allows for frame level and order level in increments for both color and density.
    To cut to the chase, this is an overly complex way of saying that logic integrators on analog mini labs are smart enough to make corrections via global bias or each frame. Basically an upgrade from an Atari 2600 to a 5200 in a technology sense. Either is irrelevant since no optical mini-lab exists on the market today capable of accurate slope corrections beyond a 2-stop range in either direction. Even those integrators that are capable of a two stop slope, do so with little accuracy because mini-labs handle mostly amatuer print films, and amatuer print films are too F'ing erratic in terms of quality to even dream of establishing a 5 stop total slope set. 1 1/2 stops in either direction was the best I was ever able to accomplish with the most stable professional print films on the market like VPS and dedicated Kodak analyzers, and even then 1 1/2 stops was a stretch. Conventional mini labs are not capable of the process Q/C, nor material control that is required for this level of population deviation. Their common inability to get neutral or even consistent prints from B/W chromogenic films is a demonstration of this and their general lack of sophistication. If you can't produce grey correctly from frame to frame, don't tell me you can produce neutral prints along a far more difficult 5 stop slope.
    In effect the technical people of the lab control this response. None of these frames would be difficult to produce on such equipment and achieve similar if not better results
    Not sure if these remarks are based out of ignorance, or some stubborn defense of analog printing - perhaps a bit of both.
    Optical mini labs are limited in their ability to make print corrections even more so than optical custom printing. They have the option of making your print darker, or make it lighter, or change the print's overall color - that's it. They cannot alter saturation or contrast in any respect, and if your neg is under exposed you are screwed and will get a grey print with little color saturation. Digital labs however can also adjust for saturation and contrast as well as non linear histogram tweaks which is why they are so desired over optical labs for amatuer film production. The Frontier can recover the small amount of shadow detail in the under neg by digitally enhancing it while I can guarantee an optical mini lab would have produced a pretty murky print. An optical minilab however would be able to handle the over neg much better because it has no film scanner with a limited dynamic range. When you optically print an over exposed color neg you simply expose the neg onto paper for as long as it takes to slam photons through it, reciprocity be damned.
    I never said I could print 10 stops over,I said from a tone reproduction standpoint only that many more stops of over exposure are built in to most negative films.......I also mentioned that 3 stops of overexposure is a practical limit,or else grain and density cause printing troubles.
    Steve is correct. I routinely handled professional print film from demanding clients and had to manually adjust and correct each frame with exacting color tolerances. Anybody in the professional lab biz will tell you that low contrast print films are capable of 2-3 stops of over exposure and far more than 10 stops of total dynamic range, but the printing software and papers are not capable of handling it, and the film starts to hurt beyond 2-stops over. 2 stops is the reasonable limit for lab software because beyond this you cannot get neutral prints because the print time gets insanely long and paper color shifts results beyond the ability of the software to compensate. I've printed entire weddings shot on 120 film well beyond 2 stops over-exposure, but it was far from pleasant, and the film was starting to lose proper tonal range. It also took 5x as long to print the entire order vs a correctly exposed wedding, and we charged the photog accordingly for being an idiot. My 14 year old cousin can get get properly exposed slides with her Pentax K-1000, so I feel little sympathy when a grown adult can't get accurate exposures with a modern SLR/TLR and print film.
     
  19. >>>>>I feel little sympathy when a grown adult can't get accurate exposures with a modern SLR/TLR and print film----Scott <<<<<< Isn't this the scary truth?Catastrophic exposure errors,due to poor camera handling skills,does seem to be a popular malady here?
    If you want to shoot weddings,learn to check your settings(fstop,shutter,flash)every damn frame!Also if you decide to carry more than a single speed of film,carry them seperately, and pay attention when you change rolls.
     
  20. Steve Levine wrote in the Ron-referenced thread:
    "All the Portra 400's can handle almost 10 stops of overexposure!
    This doesnt mean that over exposing more than 3 stops is advisable,
    it isnt." 'Twouldn't work on my camera, which only goes down to EI 6!
    That's +6 stops; 9 with +3 EV I suppose. An Agfa minilab did produce
    semi-acceptable prints at EI 6: better than most of the stuff that
    comes out of disposable cameras with Max 800 anyway. And I metered
    for the shadows, so bright spots may have been ~ +11 overexposed.
    The reason I started doing latitude tests was a practical one:
    to determine which film is best for whitewater rafting protography
    amid shady forests.
     
  21. I am not sure if I am the only one seeing this. The last scan, which is 3 stops underexposed has more details in its green foliage (i.e the lower 1/3 area) than the other two. The other scans include a shot which is 5 stops over!

    I have a hard time understanding this phenomenon. I even for a moment don't doubt the exposure latitude of a print film. But foliage is anyways a less than normal brightness area. Check with a light meter, and see the foliage is a couple of stops below that ambient light reading. So if you expose it 3 stops under, you still get most details in the last scan above????
     
  22. James G. Dainis

    James G. Dainis Moderator

    Lakhinder,
    <BR> &nbsp; &nbsp; &nbsp; &nbsp; I can't understand it either. Take a look at the clear frame area between the sprocket holes and the foliage area above it on the negative. There is almost no difference in density. (It is the same on the original negative.) To my way of thinking the foliage all should print black the same as the clear frame would.
     
  23. Here is a slightly more standardized target. Reala 120 (100 ASA) film, shot at EI 100. I have a lot of respect for this film, and
    here are some results.

    (Shot on a bright sunny day. Light measured
    with a light meter. The camera/lens combo were tested for accuracy
    separately with Fuji Provia, so that factor is eliminated. Scanning
    is done with an Imacon scanner. The files were converted to GIF,
    and I do not know what artifacts will that bring in.)

    These are not the original scans, but what
    I could correct with adjusting the Curves. Though not very religiously
    done here, I tried to make the lower left white block to similar brightness in each. That was not the only goal though.

    You can see how at 5 stops under exposure some information can not be retrieved. 3 stop under is really not too bad -- some color shift is noticable of course. And then I have +2 and +4 stop over exposure.
     
  24. Here is 3 stop under
     
  25. Here is + 2 stop over exp.
     
  26. Here is 4 stop over exp.
     
  27. Some minor additions: No other adjustments other than curves is presented.

    Also, just below the Macbeth card, in the last two scans you can see the details in a dark-green lawn-chair. Almost like the foliage in the first few scans, it is very dark. Those details are clearly missing in the first two (under exposed) scans of mine.

    (Exposure was compensated through out for 1/3 stop, for magnification of 1:10. I could have ignored it also I guess.)
     
  28. James, Lakhinder;

    To try to answer part of your questions, here is my $0.02 worth.

    The printing process compensated for each of James prints by changing exposure times drastically in each frame. This change was the printers attempt at maintaining the overall print density at the same approximate level.

    The apparent detail is actually there because at the same relative print density, the contrast of the image in the region of the trees is lower and therefore more detail appears to be there in the print from the underexposed negative. If the normal print was printed lighter, we would see greater detail there as well. Probably much more than in the underexposed example.

    Lakhinder, I suggest that you repost your scans normalizing the density and balance of the 3rd neutral step from the bottom left. These results may be quite different. The reason is due to the difficulty of balancing on the darkest or lightest patch in a scene and the contrast range available.

    Just some thoughts.

    Ron Mowrey
     
  29. EricM

    EricM Planet Eric

    "Some minor additions: No other adjustments other than curves is presented"

    well, that makes the whole excerise pointless now.
     
  30. Eric;

    Thanks for pointing that out. I missed it entirely.

    Lakinder, if you decide to take my advice and adjust for the 3rd neutral step, make no adjustments but light / dark correction. No color or contrast changes. Then we will be able to do a good side by side comparison.

    Ron Mowrey
     
  31. Eric, do you know what the Fuji Frontier at Walmart did to the negatives? No curves adjusted?

    The purpose of correcting over/under exposed film is to somehow make it look as normal as possible -- AFAIK. And as far as the film response is on the linear region, it will be easy to manipulate the curve layer in Photoshop. If I do not correct it, exactly what will be deduced from the original scan? For example, see the next two photos.
     
  32. And 4 stop over exposed shot no correction:
     
  33. Lakhinder;

    Try my suggestion.

    Correct aiming on the 3rd neutral step with no contrast correction, just lighten or darken.

    Ron Mowrey
     
  34. I'm not sure what you're trying to demonstrate, Lakhinder.

    Using an Imacon scanner, you should be able to get very good matches between the
    properly exposed negative and all of the over-exposed negatives. This matching
    should be done at the scanning stage.

    If you've scanned without making corrections then of course the overexposed negs
    are going to look totally washed out. And then they're going to look a little weird
    when you try to normalize them by making big tonal adjustments in Photoshop.

    I don't think your test reflects any real world situation - you need to start with decent
    scans.
     
  35. Elliot, there are professionals who totally bypass the corrections
    in scanning stage -- and go to 16-bit capture. So that would go against your assumption.

    Same logic applies to 8 bit scans too! I would use 16 bit scans if it were a transparency. This is obviously not. I was trying to keep the scanner software out of the loop here -- hopefully.

    Also, what looks washed out, if it corrects well in photoshop (or however), then that is what I want!
     
  36. I looked at Color Management by Fraser/Murphy/Bunting, and using the
    Macbeth chart scanned values in LAB mode, used 3rd square as the reference, and made it LAB: 67, 0, 0. (See page 221).

    So here is the series again. No other adjustment except for Brightness control, as Rowland mentioned. I could not adjust the 5 stop underexposed scan to get me the reference LAB values. So I did what I could, and left it at that. Had I adjusted its contrast, I could have reached the reference value.
     
  37. Underexposed by 5 stops. Only brightness changed in Photoshop 7.0. But could not go all the way beyond the scale maximum!
     
  38. Oops. the size is slightly bigger. Here again is -5 stop underexp.
     
  39. -3 stop under..
     
  40. 2 stops over.
     
  41. Here is 4 stop over, normalized scan.
     
  42. Lakhinder, I still don't get it... What are you trying to demonstrate?

    Are these raw scans? I thought that Imacon raw scans could only be processed by
    Imacon's Flexcolor software. They can't be opened in Photoshop, can they?

    If they're not raw than you haven't circumvented the scanner's software you've just
    got
    the settings wrong. It's like going into a darkroom, making a print of a properly
    exposed negative at, say, 10 seconds, and then printing all your under and over-
    exposed negs at 10 seconds. What's the point? You're going to get a bunch of very
    dark and very light prints.

    You're working with arguably the best film, scanner and image editing application in
    the world - and you're producing rubbish.

    Reala is much, much better than that.
     
  43. Thanks Lakhinder;

    Now we see 3 sets. Uncorrected, 'optimally corrected' and just brightness corrected. You see the range of tonality and color that is encompassed by all of these in scanning now.

    Printing is a similar process, optimizing the picture by 'normalizing' the exposure. The pictures James shows have some degree of 'optimization' built in making them similar to the best selectable from Lakhinders pictures.

    But you see that the latitude of the film is about 5 over to 3 under or 2 over to 3 under. We can establish that 3 under is the max from both tests, but the overexposure varied from 2 to 5. Since overexposure is placed on the shoulder, it may be that the shoulder of the two batches of film may be quite different, or in other words the latitude of the films differ, but the ISO and EI values are the same.

    This may be product variation or process variation. We need more tests. Heh.

    But we already knew that negative films can be under and over exposed, and now we know that at least two stops in either direction can give us usable results. One stop is apparently quite safe.

    This is a very good test and gives us a lot of information. I'm just sorry that I don't have any tests that go as far. I usually only tested plus and minus one or two stops.

    Tests like this for several batches of film will reveal to us a combination of effects of process variations and product variations which will give us save exposure limits for this product. Tests like this across product or manufacturer lines will give limits and capabilities of these other films.

    Thanks for the great thread.

    Ron Mowrey
     
  44. Eliot;

    Of course the scanner is contributing, but then the printing process contributed to James' result as well. What we are learning is how far over and under we can expose this film and get reasonable images by any means without severe losses. We are learning that there are differences in methods of testing, processing and scanning. If we keep at it long enough we will get a true benchmark for this film, not just a statement that the film is good and capable of more. We will see if it is process sensitive, if it varies from batch to batch, etc.

    I find it worthwhile.

    Ron Mowrey
     
  45. Rowland, looking at Lakhinder's latest images most people would conclude that it is
    better to underexpose Reala by three stops than to overexpose it by two.

    Does that sound reasonable?

    Rather than taking Lakhinder's results at face value I'm questioning his methodology.

    Also, I think you underestimate the role of the minilab's software in James's prints. An
    optical print of the underexposed negative would be much less impressive.
     
  46. You're working with arguably the best film, scanner and image editing application in the world - and you're producing rubbish.
    Elliot, I like the way you put it! And I also used one of the best camera/lens to do that!

    Using an Imacon scanner, you should be able to get very good matches between the properly exposed negative and all of the over-exposed negatives. This matching should be done at the scanning stage.
    And if you want to focus on this aspect, then just look at my first four scans, which are actually from the same scans I show later.

    Rowland, thanks for your observations and suggestions. I am sure my process has flaws, as also some part of my scanner software might be out of my control! One thing I will say is, that even the original normally exposed scan (which I have not posted), does not show very bright left square block. I had not shot a normal exposure in the film I had scanned above. So I did not post. I have it from a test I did with the same film batch, but on a different day under similar light! Maybe someday I ought to repeat this experiment a bit differently. Maybe do 16bit scans..!?
     
  47. EricM

    EricM Planet Eric

    "Maybe do 16bit scans..!?"

    Why would you do 16 bit scans? 16 bit is way way in the future. There's nothing that supports it for us, the best printers are 12 bit, you more than likely print on 8 bit, but weirder, you want to go through all the 16 bit effort for a 72dpi monitor?

    If you want to do something worthwhile for this thread, take a roll of your reala in 35mm flavour, do eight bracketed exposures repeated three times over, then clip the roll at a good lab, do a front end clip at push 1, a mid roll clip at N, and an end clip at -1N. Make sure the lab clips generously and record every exposure. Photograph something tightly framed and with a worthwhile tonal range, not a white blob against a white sky with some trees in the distant background. There's some here that need to see this.

    I'd still like to see those ten stops...
     
  48. 16 bit is way way in the future.
    Eric, do you know that Photoshop allows one to import 16bit scans. And many photoshop books discuss it too -- if you care to read a bit about scanning techniques.

    You still have not answered my question. Do you know what Fuji Frontier does to the curves?
     
  49. Elliot;

    My previous post went through several revisions before I submitted it, but basically it stated what you did. James' pictures are better that one would expect, and Lakhinders are worse due to the conditions of the scan / print / test / film combinations. I don't disagree with you.

    I still say that these are good experiments that teach us something. It does not say that one should draw premature conclusions before the experiment is over. There is more to do and this is just the entry point. Eric had a very good suggestion for the next step. Three or more rolls of film with the same exposures (over and under by 5 stops or whatever) with push and pull processing.

    We all will learn by each step.

    If conventional prints are made as well, we will learn how well the digital and conventional printing methods compare and what they do.

    Lets be open minded during an ongoing process and not judge hastily.

    Ron Mowrey
     
  50. EricM

    EricM Planet Eric

    "You still have not answered my question. Do you know what Fuji Frontier does to the curves?" I didn't read your posts. Your scanning on a frontier... Of course I use Photoshop. How many filters can you use in 16 bit? Do you like using adjustment layers? What do you output on? To answer your question, no. I haven't scanned nor worked on a frontier file for two years. I hope the software has been updated since. If you want to work slower with larger files, then not notice a difference when printing, go fo it. A good read on bit depth and when you should and shouldn't work in 16 bit. Make your own mind up.
     
  51. Lakhinder's last set of ColorChecker examples shows a saturation anomaly. This would happen if the lightnesses were adjusted in Lab mode, due to the uncoupling of lightness from chroma. To avoid this I would suggest adjusting the middle gray patches in RGB mode.

    Interesting thread.
     
  52. I didn't read your posts.

    I like your style, Eric! However, my style is to do some ground work and then present it. I do not mind being proven wrong. But not by empty assertions.
     
  53. Cliff you are right. That is what I did. I do not use LAB mode, but
    decided to use it to normalize the values, since my reference values were in LAB mode. I shall present again with RGB mode correction.
    Many thanks for catching this anomaly.
     
  54. I take it back. There are other things going on here.

    How are these negative scans being inverted? Invert in Photoshop produces a tone curve that is far from anything you would get by making a photographic print.
     
  55. Lakhinder;

    That might explain what was confusing me about those last samples. I think that might clarify things more. I'm looking forward to the reposts. Now, I'm for bed.

    Its late here.

    Ron Mowrey
     
  56. EricM

    EricM Planet Eric

    "I like your style, Eric! However, my style is to do some ground work and then present it. I do not mind being proven wrong. But not by empty assertions."

    Cheers Lakhinder, but "empty assertions", i don't get it?
     
  57. Some general comments:

    1. Going back to the very first 4 images I corrected and posted above, let me add that when I did the curves based correction in PS, it is not individual color correction. But only the overall curve. Which should mean brightness and contrast.


    2. Scans are handled by Imacon software-- the variable I can not
    control. I have corrected the individual curves there of R,G,B to
    produce consistent gray scale value. (That change is a new variable
    by itself! . No contrast changed while scanning, but that would perhaps be unavoidable if I correct individual R,G,B curves for gray scale.)

    3. I am not sure I can correct just by handling brightness-control of Photoshop even a properly exposed negative
    to get its image to tally with the gray scale reference values --
    I quoted above page 221 of Real world Color Mangagement. Let us forget the other colors in the chart for the moment. I need to adjust the contrast as well. And that is what I was doing originally! The first four images.

    To summarize the net result of #1 and #2 and #3 is, the whole process
    of scanning is non-linear I would imagine. (Plus the fact that the film curve is non-linear in the two extremeties.). And just controlling the brightness is not helping here. I am not presenting these images to say that this is THE way to find the film dynamic range or latitude! Just like printing off Frontier is hardly a scientific method to evaluate film response. I have already pointed out the anomaly where 3-stops underexposed' has lot of shadow detail-- the images posted by James.

    BTW, Cliff, these scans are from Imacon scanner, and are not inverted in Photoshop.
     
  58. Weather permiiting, I'm going to shoot an exposure series Sunday or Monday. I will be using EK Portra 800 film for the test. If all goes well, I hope to post some results. I may start another thread. It will take me a while to expose, process, print, and scan these results, so don't expect results this Sunday or Monday.

    I may be able to include other films in this test. IDK yet. I'm working on it.

    Ron Mowrey
     
  59. You might want to test Portra 800 under tungsten lighting (without filtration), as this
    is how it is often used (by low light photographers).
     
  60. Elliot;

    Thats what was in my camera. I was shooting a moving 2 year old in heavy shadow and sunlight Saturday, and I didn't want to waste the rest of film. As it was, my 220 back had Portra VC 160 in it, so I shot that as well. I have the film ready to process tonight. I used my RZ instead, but had some trouble with the 800, as the shutter is limited to 1/400th, so I got 1600, 800, 400, 200, 100, 50, and 25 speeds. I got the same series with the 160, but the 160 exposure is in there as well. I used even stop increments otherwise. I just hope they turn out.

    I metered through the lens, and varied the f stop for some of the exposures. I used the speed setting on the backs to vary the speed.

    Wish me luck. The hardest part will be to decipher my notes and match them to the negatives. I suspect I'll have to repeat this again to make doubly sure of my results.

    Ron Mowrey
     
  61. Today, I shot 3 rolls of film. Portra 800, Portra 400, and Portra 160 VC. I used my Mamiya RZ. The scene was composed of the MacBeth checker and a Kodak color step scale and grey card.

    The 800 and 400 did not allow a good enough exposure range due to the shutter / f stops available to me, but I got some data.

    The 160 gave a range from ISO 800 to 25.

    I have 7 exposures coming up soon. They are drying. I will scan them in first hoping for the best. I have 800, 400, 200, 160, 100, 50, and 25. That is approximately 3 stops over, and 2 stops under using ISO 100 as the center point, and 160 as the 'correct' exposure.

    I also photographed the setup so you can see it.

    Ron Mowrey
     
  62. Here are three scanned frames from the Portra 160 VC series. The left picture was exposed at ISO 25, the middle is 160, and the right one is ISO 800. Epson scans with exposure correction enabled. No photoshopping. Pasted into Paint, and saved as one JPEG image. Ron Mowrey
    008ot0-18733084.jpg
     
  63. Epson scans with exposure correction enabled. No photoshopping.

    Rowland, thanks for the experiment. I am impressed by the response at ASA 25. That is nearly 3 stop under exp.

    To clarify my results above, I did no exposure correction in scanning stage, except to match the R,G,B guns to handle gray chart accurately (Since Imacon has no profiling built in).

    I could be wrong, but looks like Epson software takes the extreme black and extreme white into account in order to correct the scan. Something which I tried to do in Photoshop, just so that I could control better. I really don't know anything about Epson software.
     
  64. Ron, again a scan suggesting that underexposure by 2 stops looks even better than over exposing, but we all (think we) know, that overexposure benefits C-41 films.
    What usually happens with underexposed neg film is that they start to get grainy, so how does your Portra look in full rez scans?

    Another note: I wonder whether scanning (hardware, software, operator) is a big factor here in these results as both you and Lakhinder get better looking scans from underexposed negs and you both seem to rely on what your Epson or Imacon software is doing.
     
  65. Well, first, Epson scanning software has the 'adjust for exposure' button turned on as default. It cannot be turned off. If you click 'set to default' it turns the button off, but as soon as you click on 'scan' the button turns itself on again. A 'depressing' state of afairs, to be sure. I wanted no image modification. I guess the only way to get that is in the conventional proofs.

    I intend to print a proof sheet of all 7 negatives on one 8x10 sheet of paper, and use 3 - one stop brackets around the center point to show the degree of variation.

    I expect that there will be severe sharpness and grain changes with that extreme of exposures. I have seen it before. Flare alone, at 2 stops over should be a big factor in sharpness. Grain at 2 stops under should be bad. But when I make 8x10s of these, that should resolve that part of the issue as well.

    Remember, I did this with 800 and 400 as well, and they showed me similar ability, but I could not get the range of underexposure due to camera limitations. Therefore, I did not post them.

    The best bottom line I can come up with right now is that virtually every color negative film can be over or under exposed by up to one stop with no significant problem for most casual users. The discriminating professional may want to push or pull process to trim the results, and they may be unhappy with the results wrt grain and sharpness.

    In a pinch, negative films that I tested seem to have a 2 stop full range latitude on either side of the true ISO in which you can get a usable (not good necessarily) result. In other words, the film won't be blank. You will have an image. Grain and sharpness are waiting in the wings for proof. I'll be getting around to that in a few days.

    Regards.

    Ron Mowrey
     
  66. EricM

    EricM Planet Eric

    Ron, can you get the Silverfast software for your epson?
     
  67. Eric;

    I just bought the Epson a few months ago. I'm still getting used to it and have not looked into alternative software.

    Ron Mowrey
     
  68. To answer an e-mail request, here are the originals, unresized in Paint, as they came from the scanner. Don't be too disappointed if there are any problems. Don't be overelated if they look better. Ron Mowrey
    008pJ0-18744484.jpg
     
  69. And the next.
     
  70. And the last.
    008pK9-18745384.jpg
     
  71. Portra 160VC as rated: dark skin is too dark, top-row green is too
    brown, red is too dark, magenta too purple, but grays are excellent.
    Does this film have too much midtone contrast, or is it the scanner?
    Similar color problems at EI 25.
     
  72. Bill;

    IDK. Wait until I get proofs on Endura.

    Then we can see what traditional prints look like. They could be awful. I hope not.

    Ron Mowrey
     
  73. Bill;

    I have the chart on my lap, and compared to what I see on the monitor for all of the scans, the pictures at 25, 50, 100, and 160 are all too light. All of them are bluer than the original. They need more yellow.

    Ron Mowrey
     
  74. 'Wait until I get proofs on Endura...'

    Hmm, I can tell you the results:

    Prints from the frames over-exposed by one, two or three stops will all look the same
    as the print from the properly exposed frame.

    Prints from the underexposed frames will look flat and lifeless.
     
  75. If anyone wants to see an sRGB-colorspace Macbeth chart to compare,
    see dpreview.com's review of the Nikon D70, page 14, or their review
    of the Olympus E-1, page 15. On my monitor these look closer to a
    real Macbeth chart than those produced by the Canon D60 (way too dark)
    or 10D (still too dark).
     
  76. James;

    I would like to extend the life of this thread if possible, or at least follow your suggestion for carryover. I have the proofs and have done more work on the Portra family of films that I am goint to post as soon as they are dry. I have more to do.

    Elliot;

    You are in for a small surprise. The proofs don't exactly agree with your prediction.

    To all;

    The 800 and 160 proofs are drying as I type. I did an over and under exposure series on-easel from 4.5 to 32 of the 160 and then just printed the 800 at the center point. First, since the color balance and exposures were right on, I know that my C41 process was ok. I made the correct exposure first time around.

    Second, the latitude of the Portra films surprised me all the way from the 800 Portra to the 160 portra. Just as a teaser, with appropriate exposure, the prints from the 160 looked good from 800 to 50. The 25 was pretty bad. Looks like the film is more of a 200 speed than 160 in my camera. The prints with the 160 exposed at 800 indicate that with no push, usable prints are obtainable.

    I plan to do some work with the 400 and 800 to get more data, and enlarge some of the negatives up to maybe the equivalent of 16x20 for sharpness and grain. It is so hot here that darkroom work is kinda ungood though.

    Summer finally arrive in Rochester. Maybe it will snow tomorrow, who knows.

    Ron Mowrey
     
  77. James G. Dainis

    James G. Dainis Moderator

    Ron,<BR> &nbsp; &nbsp; &nbsp; &nbsp; This thread is not going to disappear. It will be in the archives for a long, long time. I didn't expect this thread to go so far. I started it because I accepted Steve's challenge to get out of the armchair and over/underexpose some film, and was rather surprised at the results.
     
  78. Thanks James.

    The results I have as straight prints are going to surprise you as well.

    They are dry now, but it is too late to scan tonight. I'll have a few posts here tomorrow.

    Ron Mowrey
     
  79. FWIW, I decided to make a Macbeth chart with the values as per the reference I quoted above (i.e Fraser/Murphy/Bunting, pg 221). This might come in handy as a point of comparison (or confusion?). This chart was created in RGB mode, and then saved as Jpeg.
    008qPK-18774084.jpg
     
  80. Here are the proof prints. I will be making 4 posts of the individual proof sheets. The center point on my enlarger is f16. The first is f5.6, or 3 stops over exposure, therefore the ISO 50 and 25 exposures are more properly exposed. I would have done better if I could have given them one more stop. Print order from left to right, top to bottom. ISO 160 check. ISO 800, 200, 50. Bottom row, ISO 400, 100, 25. Portra 160 VS.
    008qgM-18781384.jpg
     
  81. To continue, here is f8. Any blemishes you see are due to the plastic negative file which held the negatives in place.
    008qgT-18781484.jpg
     
  82. Here is f11
    008qgV-18781584.jpg
     
  83. This is the center point, f16, on my enlarger. It gives properly exposed prints for normally exposed negatives at this light intensity. Remember, these are contact proofs with the negatives in a plastic carrier to hold them in place, and a glass proofing easel.
    008qgg-18781684.jpg
     
  84. And finally f22. I did f32, but the d-max was down and the prints were not very good. I also did the 800 speed.
    008qgl-18781784.jpg
     
  85. As a final note, the scanning and uploading process introduced artifacts such as the red mottle in the d-max (black) areas of the prints. It is quite obvious in the f22 print.

    We can only make generalizations about the grain and sharpness, but it is quite obvious that the 160 film is usable from 800 to 25 with quite good results between 400 and 50. I can say the same about the 400 and 800 films within the limitations of my camera. The films looked good there up to 1600.

    I left the images at 1:1 (8x10) even though this makes it somewhat inconvenient to see the entire print. I suggest you download them and view the smaller versions in Photo Shop. I did not apply any correction to the images during scanning. No dust removal (obvious heh) and wanted you to see them as is, as much as that is possible with any conversion like this. They were treated like any other proof print in my enlarger. The extra care goes into the final prints, so please excuse my dust.

    This is not my idea of a 'good' test, but was one I could run in limited time and with limited resources. A good test would include at least one, preferrabley 3 models to test various skin and hair colors, and would also include exposures indoors with flash and tungsten light.

    I would like to see the same series on Fuji 160, 400 and 800 run to see how it does. Anyone out there up to it.

    I commented before that my C41 process was in control, as these prints were all right on my centerpoint for balance and speed. The process included a total of 2 220 rolls and 4 120 rolls 3 of which were these tests and the other 3 were my own work.

    In the near future, I hope to enlarge just a portion of these frames to the equivalent of 16x20. That is why the chart is small on the frame, so it gives me that leeway. That should give us an idea of grain and sharpness. I did not have the resolution charts printed yet to include in these tests.

    Regards.

    Ron Mowrey
     
  86. Lakhinder Walia's color chart looks muddy to me, so here's another
    that more closely matches Nikon D70 or Olympus E-1 output. It's in
    GIF so you can adjust individual color patches more easily.
     
  87. 'Elliot - You are in for a small surprise. The proofs don't exactly agree with your
    prediction.'

    Huh? I think they agree exactly.

    This is what I said:

    'Prints from the frames over-exposed by one, two or three stops will all look the same
    as the print from the properly exposed frame. Prints from the underexposed frames
    will look flat and lifeless.'

    And that is what I see in your test results.

    All the overexposed shots look fine. Ok, the shot that's a 1/3 of a stop underexposed
    looks alright too. But as soon as there is any significant underexposure (the frame
    rated at 400ASA (i.e. 1 1/3 stops under)), I see a critical lack of contrast that leads to
    a flat and lifeless image (I'm looking at the last contact-sheet you posted).

    There are no blacks in the image rated at 400ASA, and if you printed it down there
    would no whites. The image at 800ASA is flatter still.

    Of course there is a degree of subjectivity in claiming that these underexposed
    images are either 'good' or 'acceptable' - I mean they're better than nothing - but I do
    know that my clients would find them totally unacceptable. That is why I always rate
    neg film at 1 stop over - then I have a safety net if the cloud thickens slightly or the
    model backs off from the softbox.

    This thread evolved from another thread in which Steve Levine claimed that good
    results could be had by uprating your film by as much as three stops (e.g. rating
    400ASA film at 3200ASA) and then processing normally (I believe James was
    referencing this thread in his title). And James's results seem to bear Steve out (I
    wonder if they both use the same type of minilab). James's 3 stop underexposed print
    has remarkable shadow detail and contrast.

    I am sure that this is all down to the software that the Frontier minilab employs.

    Those who use Frontiers or other digital minilabs should pay attention, because
    getting an extra 3 stops out of any colour negative film is A VERY BIG DEAL.

    But for the rest of use who still prefer analog prints over digital prints, the old advice
    remains the same - whatever you do, DON'T UNDEREXPOSE COLOUR NEGATIVE FILM.

    (Thanks for taking the time to run the test. It took me a while to decode it. It would
    be nice to see colour-corrected 8x10s from each of the brackets).
     
  88. Just a small nit to pick. Earlier you said:

    'The 25 was pretty bad.'

    The 25ASA exposure only looks bad because it is fogged. This is a side-effect of the
    contact-printing process. If you placed the neg in a masked neg carrier and made a
    print, I'm sure it would look very nice.
     
  89. Elliot;

    Please compare the 160 exposure at f16 with the 400 exposure at f22. They are a close match in overall contrast and color saturation, and the color quality isn't bad. The 800 actually looks better than the 400 in the f22 proof. Of course the background is not great. The contrast in the holly bush is low, as to be expected, but it isn't as you said that "Prints from the underexposed frames will look flat and lifeless".

    Of course it isn't perfect, I never said it would be. But consider that this was with straight processing, and not a push. With a push, the results would probably be even better.

    So, I think, given the words you used, the prints of the 400 and 800 are not flat and lifeless. And with a push, they would improve.

    Under some conditions, people can expose the Portra 160 to 800 and get (my words) usable results. This is better than losing the shot entirely. Under some conditions, using 400 at 800 or 1600, and 800 at 1600 or 3200 will give usable results as well. Pushing of any of these films will improve the quality somewhat. I think we agree on this.

    Also, some manipulation on-easel and individual correction would make these prints even better, I think. There is not much color balance shift in the exposures. How do you think individual color correction would help?

    Again, I wonder how a similar test with Fuji film would look, with the use of the color chart.

    I think we were surprised at James' tests, but mine tend to agree with his. In addition, I believe Steve Levine said negative films have 10 stops overexposure latitude.

    I do agree with you that this type of mistreatment of film does not yield the highest quality. If you rate film 1 stop over, then you would rate 160 at 320? Do I take you right? Or did you mean 1 stop under and you would rate 160 at 80? I usually rate my films under by about 1/3 stop. This gives me latitude when I need it, not the other way around. Your statement is not clear to me. It seems to indicate the opposite of what you want the way I understand things.

    By underrating films ISO, you overexpose it, and by overrating an ISO, you underexpose it. Therefore, 160 at 80 is underrated by 1 stop, and the negative is darker or overexposed, but at 320 it is overrated by 1 stop and the negative is lighter or underexposed.

    It seems to me that the films I tested are slightly underrated from the actual EI that I observed. That is a good conservative measure.

    Ron Mowrey
     
  90. 'Please compare the 160 exposure at f16 with the 400 exposure at f22.'

    Ok, So that's top left on the penultimate contact sheet compared to bottom left on
    the final contact sheet?

    'They are a close match in overall contrast and color saturation, and the color quality
    isn't bad.'

    Whilst you see prints of a similar quality, I see a good print and a bad print. I don't
    see a 'close match' in contrast at all.

    How come?

    I guess you're focusing on the colour chart (a low contrast target with maybe a 3 stop
    range), whereas I am looking at the whole image (the chair, the chair's shadow, the
    bush, and even the neg rebate).

    If you look at the whole image I'm sure you'll agree that the 400ASA image suffers
    from a significant reduction in contrast.

    I'm more interested in the whole image than the test chart, and to me the 400ASA
    image shouts 'underexposure!'.

    --------------

    'With a push, the results would probably be even better.'

    Agreed

    'So, I think, given the words you used, the prints of the 400 and 800 are not flat and
    lifeless.'

    We'll have to agree to differ on this.

    'Under some conditions, people can expose the Portra 160 to 800 and get (my words)
    usable results. This is better than losing the shot entirely.'

    In what scenario would someone 'lose the shot entirely'? In most cases, I would prefer
    a punchy print with a little blur to a flat print with critical sharpness.

    'Also, some manipulation on-easel and individual correction would make these prints
    even better, I think.'

    Yes, you could print on Endura Ultra and then burn around the chair to try to pump
    up the contrast.

    'There is not much color balance shift in the exposures. How do you think individual
    color correction would help?'

    You're right - the colours are fairly similar. The densities are quite variable though,
    which makes the test a bit confusing. I just meant it would be nice to see the brackets
    fine printed to a closest match.

    'I think we were surprised at James' tests, but mine tend to agree with his.'

    I don't think so.

    'If you rate film 1 stop over, then you would rate 160 at 320? Do I take you right? Or
    did you mean 1 stop under and you would rate 160 at 80? I usually rate my films
    under by about 1/3 stop. This gives me latitude when I need it, not the other way
    around. Your statement is not clear to me. It seems to indicate the opposite of what
    you want the way I understand things.'

    Yes, sorry, I got confused - I meant that I always over-expose negative films by one
    stop. So I rate Portra 400VC at 200 (metering with an incident lightmeter).
     
  91. Elliot;

    Thanks for the clarification.

    I think there are two differences here to be resolved. First, I'm looking at the actual prints and you are looking at scans. I believe that under good illumination the prints appear closer together than they do in the scans.

    Also, I was not clear in my last post on what images to compare.

    f11 print - upper right (ISO 50)

    f16 print - leftmost single (ISO 160)

    f22 print - left lower (prints should have better match) (ISO 400 bottom)

    Or:

    Leftmost print in f11 example (ISO 160) vs lower row left (ISO 400) of f16. These two in particular are quite similar even in the shadow detail and are quite good in saturation and contrast.

    In full daylight, in the original. these look very good and with precision printing more could be done to match them.

    As I said above, this test is rather simplistic having no real flesh tones for comparison, nor have we compared different illuminants. And, as you have said, no true professional would do this intentionally except for special effects or to capture a scene that otherwise would be lost. There have been scenes that I have taken that needed the capture with no motion, in direct opposition to your suggestion of capturing with blur. This is particularly true in high speed motion detection for engineering purposes where such exposures may be necessary.

    In the final analysis, photographs of charts is nice, but can be misleading. You can't sell these photographs. You need real subjects, but the charts help calibrate possible ranges available for use when necessary.

    Oh, the ISO 25 scan is worse than the print cf the bottom right of the f8 example. I don't think I had the prints in hand when I made that comment, but if I did, I had misevaluated the ISO 25 results.

    Again, thanks for your additional information.

    Regards.

    Ron Mowrey
     
  92. Yes, when compared on the darker contact-sheets, the 160 ISO and 400 ISO images
    do look more similar.

    I can still see the faded look of underexposure in the 400 ISO image (especially in the
    bush), but I can accept that for some people this wouldn't be a big problem.

    Regarding overexposure, many people seem to believe that by overexposing they can
    increase a film's saturation and contrast (I think there's a thread running on this topic
    at the moment). My tests indicate that this is not the case with Kodak's Portra films.
     
  93. Elliot;

    See Joe Manthey's explanation and elaboration on this in the other thread.

    In as much as you increase contrast, you increase saturation. However, it depends on exposure, film and a lot of other factors. Sometimes, contrast can give the subjective illusion of increased saturation. Just as increased contrast can appear to increase sharpness.

    This is all bound up in the way the eye integrates an image, but the film is analong with no integration (in a sense) and digital is of course, digital.

    I plan on trying some additional prints to try to match the various exposures. I'm curious as well about how these 3 films perform.

    Well, thanks for the clarification. I think we are pretty much in agreement. Overexposure is good, and underexposure is bad. Correct exposure is best and professionally desirable.

    Sometimes over or underexposure is expedient, and within limits can give limited acceptable results. Over and underexposure are usually limited to a max of about 3 stops on either side if you want usable results, but 1 stop if you want more acceptable or professional quality results with overexposure preferred.

    Underexposure with a push process is sometimes useful.

    Does that seem to summarize things?

    Thanks again.

    Ron Mowrey
     
  94. 'Does that seem to summarize things?'

    Yes.

    But for my way of working, Portra's window of good exposure is from box speed to
    about 3 stops overexposure.

    I see no negative effects from overexposure within this range.

    With even slight underexposure, I feel that Portra films suffer a reduction in contrast,
    which produces a flat print.

    As well as always exposing Portra films properly, I often push process these films to
    gain additional control of colour and saturation. A half stop push is fairly standard for
    me. On occassions I'll push up to two stops.
     
  95. Sorry, that should read:

    'to gain additional control of CONTRAST and saturation'
     
  96. Elliot;

    I certainly can't disagree with you. However, others have stated in other threads here that pushing does not increase saturation and have cited the Ctein review to support their position.

    I agree with you and disagreed with their assertions. I believe that a push will increase contrast and saturation. There is support for both views on the other thread.

    The contrast and saturation levels increase in varying amounts from film to film. Therefore, one may see a small increase with one film and a larger increase with another film. In that, I agree with some of the observations posted.

    In addition, I would like to add that the pictures I posted were under optimum lighting conditions whereas normal underexposures would usually be done with poor lighting. This predisposes the photographer and those who view the underexposed results to refer to them as being flat and desaturated due to the poor lighting.

    I would like to suggest then that the flatness and drabness we associate with underexposures, often comes in part from the lighting conditions that led to the need for underexposing the film in the first place.

    Anyone care to comment on that?

    Ron Mowrey
     
  97. "I would like to suggest then that the flatness and drabness we associate with underexposures, often comes in part from the lighting conditions that led to the need for underexposing the film in the first place.

    Anyone care to comment on that? "

    Sure.

    Mostly under dim lit conditions the color balance is off, especially under tungsten light. Inevitably (at least) one of the color layers gets less exposure than the others (=underexposure) and you either end up with a flat tonality or if you try to correct for this (especially in the digital [minilab] domain) you'll amplify the grain.
     
  98. Bernhard;

    I agree.

    What about the pictures above then? They were made with 'good' lighting. No rebalancing was needed. Does this mean that over and under exposures are made better when used with good light sources, or that over and under are made worse by the bad light sources.

    If so, then I would infer that it is more acceptable and useful to use underexposures in particular when the light source is balanced and bright, and avoid some of the consequences of having to rebalance a tungsten or other 'bad' source.

    This is the way I am leaning right now. The underexposures were surprisingly good in good light. I have done enough available light to recognize the grain and balance problems you point out. I have also done enough underexposure in good light to indicate that problems with washed out color and grain are minimized in this good light to make it more acceptable.

    Ron Mowrey
     
  99. "If so, then I would infer that it is more acceptable and useful to use underexposures in particular when the light source is balanced and bright, and avoid some of the consequences of having to rebalance a tungsten or other 'bad' source."


    I agree (also with the rest of your post).

    When shooting under tungsten balanced light I give more exposure, depending on how much color balance correction I intend to up to 1 1/2 stops with Press 800.
     
  100. 'When shooting under tungsten balanced light I give more exposure.'

    Me too. Portra 800 needs an extra stop and a half under tungsten, if it's going to be
    fully colour corrected during printing (any less exposure and you get weak blacks
    with a blue cast). Alternatively, I'll use a Lee 80A filter which soaks up a stop and a
    half of light.
     
  101. jtk

    jtk

    What has been learned here?

    Reference images lacking Kodak girls always wind up in this kind of debate. Macbeth charts are primarily intended for densitometry, not for eyeballing comparisons such as this thread's.

    We need more girls, multiple ethnicities. Yes!

    Scanner differences: some scanners adjust for exposure using software alone, others adjust intensity. My old Epson 3200 depends on software, my Nikon V adjusts intensity. The Nikon's much better than the Epson with decent negs, but it fails entirely with extremely dense negatives: Epson actually does better with extreme density, just as would an optical enlarger

    Epson scanners mostly come with Silverfast SE. Silverfast SE has a much bigger range of film emulsion curves (most of which are long-forgotten products, but which can still be useful).

    It'd be mildly interesting to play Silverfast SE against Epson scan with ultra-dense negs.

    However...neither rivals Vuescan...
     

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