Largest print size from medium format ?

Discussion in 'Medium Format' started by john_dowle|1, Jul 22, 2011.

  1. Does anyone know what are the largest print sizes from medium format, 6x4.5, 6x6, 6x7, 6x9 etc...., I was wondering what size you can print up to and keep optimum quality. Thanks for any help as usual.
  2. Thats a bit like asking how long is a piece of string, but suffice to say MF can outstrip Digital and if you want to get a Drum scan done then you are miles in front. After that get yourself a workstation with megga memory and Prefect Resize 7 and take the whole lot even further. One essential point in all of this is that your original image be as sharp and well defined as possible, I am putting 15mp files through PR7 and achieving some outstanding results with a print resolution of 300dpi, please don't confuse resizing in Photoshop with PR7> Photoshop is a total mess, sorry to say that but the output is dreadful.
    Optimum quality in the finished product is totally dependent of the initial image and nothing else.
    But just how far do you want to take you images.
  3. It depends. On the film used and the tools used for capture. I have a 30x40 print on a wall in my office that was made with the large print in mind. I used a tripod, remote camera release and put the mirror up before final capture.
    Also, keep in mind that the larger the print the farther back the viewer usually stands to look at it.
  4. I usually shoot 6 X 6, but crop, so it's effectively 6 X 4.5. I can't physically print larger than 11" X 14" in my darkroom, but have printed 20" X 24" in a friend's darkroom and could have gone much larger, given bigger trays, paper, and enlarger.
  5. Photoshop is a total mess, sorry to say that but the output is dreadful​
    What is that saying about a workman who blames his tools? It's so strange that no one else seems to have noticed this 'fact'.
    Like that piece of string, the size you can print to depends on many variables, particularly including how close the viewer is to the print.
    Even 35mm film was on some occasions enlarged to billboard size (18x60 feet, ) and displayed by Kodak in Grand Central Station in NYC.
  6. A lot of factors go into how big a print can be made optimally. I have printed 645 negs shot from a Helicopter chasing a train at 40x60 with iso 400 color neg film and they were incredible--but the grain was obvious up close. At a reasonable viewing distance, they were flawless (scanned on an Imacon and printed through a RIP). I never saw it, but one was printed for display at 8x10 feet and I heard it was incredible as well (I don't think I would have thought so as the photographer, but non-photographers have very different perspectives on these things.)
    Everyone has their own "Optimal" definition as I suggested above, so one can only experiment and see where your tolerance is. Not all lenses and cameras are created equal either. I have some images shot with a different 645 camera that I wouldn't probably want to print much larger than 24x30 or so--if that. So it is a matter of taste as well as what you worked with through the process.
  7. I apply a rule of thumb of 10x linear enlargement for absolute maximum print size, so a 6x6 neg would give a maximum print size of 24 x24 inches. That said, it all depends on what film you use and how good your technique is. Personally, I would not enlarge a 6x6 neg above 16 x16 inches. Generally, a larger print will be viewed from a greater distance so faults would be less apparent.
  8. John,
    Back in the studio days, I made many prints up to 40x60 from 6x6 Hasselblad negatives. These would all have been done on Kodak's old Vericolor negative stock. 16x20's and 20x24's are a piece of cake and if you shoot from a tripod with a cable release (and consider mirror up exposures), you will have no trouble going as large as you wish. By the way, I've seen similar size images from a colleague who used an early model RB67 with the early lenses. Shooting and lighting technique can contribute or detract from the image quality, so be careful with how you handle the camera.
  9. I've seen 6 foot high prints from 6x6cm that were as sharp as you could ever wish for a print that size to be. OTOH I've seen murals from 5"x4" that were horribly soft.
    One thing to bear in mind is that depth-of-field is geared to the final print size, and if you stick your nose right up to a giant print, then hardly anything will appear to be in focus - so f/22 becomes like f/2.8 on a smaller print at normal viewing distance. Step back to where you can view the whole print and everything snaps back into focus.
    If the viewing angle (not distance) is kept the same, then the apparent image quality will be almost identical whether the print is 4 inches or 4 metres across. Then there's the pictorial or interest factor of the image itself to take into account. If we find a picture aesthetically pleasing we tend to step back to admire it, but if we're interested purely in the subject matter or technical quality then we tend to lean in to examine it more closely. For example; would anyone criticise Edouard Manet's paintings for their lack of detail?
  10. I too use to go as large as 40X60 from my Hasselblads with the 150MM CT* and VPS film.
    A good tripod is a must, no photoshop, no tricks, just a straight print from the negative.
    And I could have probably gone larger!
    But I found I could go no larger than a 16X20 from my Mamyia 645 with the same focal length and tripod.
    The optics do make a difference when you are going large.......not trying to start a war. Just my experience with my equipment, same film size involved.(you mileage may vary)
    That's why I changed to all Hasselblad back in 1980, to be able to sell larger prints........started out with the 645 in 1974, switching from 35mm.
    In smaller print sizes I saw no difference between the two cameras.
  11. david_henderson


    It depends. It depends on so many things , some of them qualitative, that the real answer is almost certainly as big as you want or need or can cope with.
    These factors are important
    • Is the photograph as sharp as it can reasonably be, which probably means made on a good tripod and head?
    • Is the exposure spot on?
    • How are you going to make the prints? If analogue then one set of numbers will apply. If scanned and printed digitally then another.
    • What are you going to use to scan the original? The print size potential will be very different if you answer "flatbed" than if you say "drum scanner".
    • Who is scanning? Is it you with a scanner that you've just bought, or a lab fully conversant with how to get the best from their scanner? Or is it you with a film scanner with which you are fully skilled at producing big scans and have all the accessories necessary to keep the film flat whilst scanning.
    • Who is going to make the print file and how experienced and skilful are they at optimising the scan for printing, including the various methods and points to apply sharpening?
    • If analogue, what constraints does the enlarger place on the size of print practically available?
    • How close will the finished print be viewed ?
    • What are your atandards and expectations?
    There will be other factors that I've forgotten. For me, the answer has generally been that I haven't been comfortable beyond say 20" sq from a 6x6 original using analogue processes, in my case prints from slides. Using scan and print digitally I have little difficulty in getting prints 36" sq from the same originals, and I could probably go larger - these prints do not depend on viewing from far away for their apparent sharpness. Sp long as you can flex viewing distance with quality, you can have as big prints as you can get someone to make.
  12. It all depends on the end resolution you are prepared to accept, and which back. If you have an 80 megapixel back, and want to print at 300dpi, you can print at 34.4" x 25.8" / 874mm x 656mm
    If you're happy to print at 200dpi (which should be fine for a large print) then you can print at 51.6" x 38.7" / 1311mm x 984mm
  13. I think everyone has touched on the type of film and the technique used so I'll just talk about an average shot. First I have to say I shoot
    with a Mamiya RZ 67 Pro and some Fujifilm Acros iso 100 black and white film. I have the film processed online and then when I get
    them back simply scan on a not so expensive canon 9800?? I usually print on an Epson R1400 that prints up to 13x19 just fine. I
    have had some scans drum scanned and then printed online as large as 24x36 without any problems. I also had some 24x36 prints
    done from a digital file that came out of a Kodak DCS 14n and I have to tell you the prints look just as amazing as the medium format
    scans. I didn't want to believe it but I looked very closely to both prints and they are almost identical. I wish I could show everyone
    both prints side by side.

    I do have to say that the film looks very different than the digital but equally as good. The Kodak has this artistic almost acrylic paint look to it. When you look at 100% crop you can see what appears to be brush strokes. Weird huh?

    I guess what I'm trying to say is if you take great care in the capture process you can achieve anything.

  14. No offense Eddy, but if you scan it with a Coke bottle, a web cam will be as good as the RZ.
  15. “…I was wondering what size you can print up to and keep optimum quality.”
    I could print up to 16x20 inches because that was the largest size paper and easel I had for my enlarger.
  16. Dave I am shocked that you would say that about my dear beloved RZ! The canon scanner I use is not great but far from being a
    coke bottle. I can also attest to drum scans because I have done lots of them in my time and I can say that some are not as great as
    the price being asked. I still say that the RZ is one of the best cameras ever made and still produces great images. That's my story
    and I'm sticking to it!

  17. I have made excellent prints up to 32x24 inches from Velvia with a 645 camera and a quality scanner. My printer is 24 inches wide, thus that is the largest I have tried.
  18. He was not talking about your rz but about your scanner, i scan with a similar scanner to look at my negs (from rz too)
    and when i scan for printing on an imacon i can see a huge difference, even more difference when printing analogue
    (which I love).
  19. Thanks for clarifying Sander. I agree but sometimes I get some real crapy scans from a drum scan even though it's not
    the norm. Can't help what others do. I wish I had enough money to spend on a drum scanner so I could do my own
    stuff but man those things are expensive!

  20. Well, you can print very large. Read more details here - it's about Fuji rangefinders 6x9 format and image quality
  21. Good drumscans will always be better than the best flatbed, if you want to get all yhe benefits of using a good medium
    format camera you need good scans, if you say you are happy with flatbed scans, I think you've not made a good
    large print.

    To stay on the subject, I make analogue 90x90cm prints on a regular basis which I find very pleasing.
  22. Thank you all for your responses, Jens, the Fuji GW690III images on your website are superb, many thanks.
  23. JDM has a long way to go before he reaches to pinnacle of perfection, he sadly has problems reading QUOTE >
    What is that saying about a workman who blames his tools? It's so strange that no one else seems to have noticed this 'fact'.
    Like that piece of string, the size you can print to depends on many variables, particularly including how close the viewer is to the print.
    Yes the output in Photoshop is a real mess, but I don't use Photoshop it's not one of my tools I choose to use for resizing, but JDM elects to criticise me for mentioning that fact I use PR7 and I am far from being a poor workman JDM, his ideation regarding prints is somewhat adrift of reality, I always ask people to step back and view the canvass in all it's totality and then step forward and look at all the fine detail that you could not see from afar.
    Well PR7 has done some magnificent work for me, and will continue to be my No1 tool in the future, Cheers OnOne.
  24. Adrian, you and no software can render more details into an image after it has been captured.
    This translates into the simple fact that a scanned image with a size of 12.900 x 8.600 **native** pixels definitely features more details than any currently available digital system - at a color depth of 48 bit or 16 bit per channel of course.
    As good as Perfect Resize might be, if the detail is not in the original you need a magician to squeeze them into your file in the post process.
    As I've written in my article about the resolution of a 6x9 camera loaded with ASA 100 slide film, a perfect prints size from a standard scan @ 4.000 ppi gives you a print size of 3,4 meters x 2,27 meters or 11,16 feet x 7,45 feet without any resizing.
    Read this article to understand the resolution topic.
    After that, you might read the rest about resolution and resolving power
  25. I don't think we are on the same wavelength, problem is I have never claimed that PR7 will put detail into an image, it will however preserve detail to an outstanding degree, where you will find other methods of enlargement will loose detail.
    Sorry you are entertaining ideas that are too far off the beaten track for me, please don't make the stupid mistake of thinking I'm just a Digi Pixie merchant, I have a couple of Fuji GX680's and all the bells and whistles that go with them.
  26. Jens, I just had a look at your article on resolution, in which you claim that 35mm Velvia is equivalent to 175 megapixels of digital capture. I'm almost speechless - it's completely false and misleading. Please show me just one 35mm colour scan which can even keep up with a 22 megapixel equivalent. This test can easily be done with the same lens, to keep things consistent. So far, I have seen many film v digital real world tests and 35mm film seems to be equivalent to 10 MP or so. Velvia might beat the average 100 iso film stock but not by a factor of 17!
  27. Graham, I'm sorry, but I've laid out the math behind it. Do the math for yourself. It's not the mega pimples that count, it's the resolution and resolving power. Follow the links in my articles, ask aunt google for more information. Resolution doesn't mean pixels, it means the separation of a white and black line.
    This is a 35 mm Provia 100 F slide, scanned @ 4.000 ppi @ 48 bit color depth:
    This a a crop of the above image. No, not a 100% or 1:1 crop, it's enlarged to 200% (of the red rectangle in the above image):
    Show me your 10 MP image and with the same crop, and then let's talk. But not BS, let's talk about bare facts. Hard visual facts.
    Even with a higher res digital cam you will end up with blocky squares at this level of magnification and detail.
  28. I'd be happy to do a comparison with you, but without the same lens and subject matter it's a bit pointless. I did take this photo the other day though. I've enlarged about the same area of the image. Where the film crop is very blurred and noisy, the digital crop is full of detail. It's not even close.
    100% Crop:
  29. Wow >>--------> That is dreadful, however do you put up with that, I would have burned my cameras if I had to put up with that, it's dreadful, come on change your camera and lens.
  30. Sorry Graham, I was not referring to your set of images, afraid sometimes it's like hard work if these guys have not seen or worked with the latest software, gets difficult to explain to them about the end result and striking a balance between initial image detail and when to let the digital process take over.
  31. No problem - I understood your comment :)
  32. Sorry, but your sample is a fake:
    If it is a 10 MP camera, you usually have a lot more DOF than a full frame - as shown in the original image.
    However, in the second image it is obvious that you've used your zoom lens in a tele position: the bush at the lower left corner is out of focus, while it is completely in focus in your so called 'original' image.
    That's typical for digital shooters. Most of them can't master the math behind photography, and when they start to 'prove' that digital is so much better they start to lie and deceive - like you in your allegedly 100% crop with the thin DOF which reveals that you've used a zoom or tele lens for the shot and not a cut out or crop of the posted original.
    Come on, give me a break, you can not hold a candle to me and you will never be able to even come close to the quality, color depth, resolution and resolving power of film with your toy camera.
  33. That's a disgraceful comment. Not only is the photo real but I never claimed it was a 10MP shot. Double fail.
    I sense that you are getting desperate as everyone can see the digital file annihilated the film file. It's sad that you can't accept the truth, but that's your own issue. What's sadder is that you make it your mission to spread this misinformation around the internet.
    Why don't you put your money where your mouth is. I'll bet you $10K right now that this photo is real and I have the RAW file to prove it. I accept Paypal ;)
    p.s. I don't even own a zoom lens
    p.p.s. after Jens has paid up, I'll post the raw file for everyone to see :)
  34. Jens > Give it up, you're fighting a loosing battle, you are working on nothing more than assumptions that are bordering on the delusional, I have some of the finest film gear ever made and I know how to use it and what film is best for my purposes, but I'm not bigoted and I have embraced the digital world and been rewarded for it. Please don't start preaching until you know who you are preaching to, it can get embarrassing, and I'm certain that is not here as a sounding box for Bigotry.
  35. Whilst Jens's film crop appears believable, Graham's crop has too much detail. Even if it were a 5x4 piece of film, I doubt that there would be that much detail - especially in the hairs in the ears.
    everyone can see the digital file annihilated the film file​
    Not everyone can see that.
    p.p.s. after Jens has paid up, I'll post the raw file for everyone to see :)
    How about offering to send some of us a JPG of that RAW file by e-mail so we can see for ourselves? (before you get your $10,000!
  36. Steve, what size is Grahams file ?
  37. Ok, it seems a few film buffs out there are a bit out of touch with what digital can do (and one is just out of touch with reality completely) so here is the full-frame digital file, converted to JPG:
    This all started with Jens' outrageous call that a 35mm Velvia is equivalent to a 175 megapixel digital capture, and I can assure you my digital camera is far from being 175MP! I hope that Jens removes that ridiculous article from his blog now but I doubt it. His head is firmly in the sand...
    Jen's crop posted above just confirms my suspicions about film - it looks very similar in detail to a 10MP digital file, scaled up.
  38. We are still waiting for your promised 10 MP file for a valid comparison.
  39. Jens, I made no such promise and frankly I see no point in responding to you after you've proven how rude and ignorant you are. The file is real and you made a fool of yourself, and now everyone knows it.
    My above post is for everyone else who is interested in the truth. I'll let the image speak for itself.
  40. Well, that file is not a full frame shot, it's a Leaf Scan Back image:
    As I said: most digital shooters are liars... talk about a 10 MegaPixel image and posting a large format digital image from a scan back.
    We are still waiting for your 10 MP image from a full frame camera you liar...
  41. OMG your stupidity has no limits. It's not a scan back. Research it for yourself. You do know how to use google, right? Secondly, a scan back can't make an exposure at 1/200.
    If you actually believed what you're saying you'd take that $10K bet. Now it's pretty obvious that you are trolling.
  42. Graham Mitchell said: Jens, I made no such promise​
    You did:
    Graham Mitchell said: So far, I have seen many film v digital real world tests and 35mm film seems to be equivalent to 10 MP or so.​
    And then you post a 'full frame' image which actually is a Leaf Scan Back digital file - NOT from a 35mm system for a valid comparison.
    Dishonest liar.
  43. Steve, what size is Grahams file ?​
  44. Gentlemen! Gentlemen!<br><br>While i do know that anyone who thinks 10 MP gets anywhere near 35 mm film quality must have been inspired by the burning of some hallucinogenic herb ;-), and that file size is the least significant metric imaginable (!), it serves no purpose to let tempers fray.
  45. Graham's file measures 10,300 x 7,752 pixels so is from an 80MP sensor. Despite my previous reckoning that there was too much detail in the crop, a similar crop of the large file gives the same image.
    This shows that there is a lot of detail in an 80MP image. This is to be expected but it is a bit better than I thought it would be. However, the crop from the film image is very good too considering it is only a 35mm frame.
    In reality, the posted images show how good both recording mediums can be when used correctly and should not be used to show that one is superior to another. Whilst Graham's 80MP image does have more detail than a 35mm film image, it would be easy to go up to medium format then 5x4, 10x8, etc. if winning a resolution war was really important.
    The reality is that both film and digital are now capable of very good results and the best one to use is the one which suits you best and which you are happiest using.
  46. Hi Steve, I'm glad you got the file. I wasn't posting to say digital is better than film (I'm an ex medium format film shooter myself). I posted my file to demonstrate how ridiculous Jens' claim was that a 35mm film image could be equivalent to 175 megapixels - more than double the resolution of the high-res file I posted. I really dislike seeing such online 'experts' evangelically publishing such false articles and perhaps encouraging people to buy the wrong equipment for them. And yes I have seen film v digital real-world tests which put 35mm film in the 10MP range.
    You might find this article interesting:
    It was written a few years ago now, and compares 39 megapixel digital with 4x5 drum scanned film. The conclusion was that it was very close and that the film still had the edge. Since then, many 4x5 film users have compared resolution with 80 megapixel backs, and found the digital backs to out-perform film. So it seems fair to equate drum scanned 4x5 film with around 60 megapixel digital.
    How anyone believes that 35mm film can come even close to 4x5 film is beyond me.
  47. The point is that Graham stated that a 10 MP image is on par with 35 mm film, so I posted a 35 mm sample. Then he posted an 80 MP image to 'prove' his statement for the resolution of 10 MP without mentioning it is an 80 MP image - comparing apples to bicycles for his false statement.
    As Q.G. de Bakker said: anyone who thinks 10 MP gets anywhere near 35 mm film quality must have been inspired by the burning of some hallucinogenic herb.
    So, we are still waiting for Grahams 10 MP digital image... or even 12 MP from a 'full frame' system as he stated. For a viable comparison!
    I have posted some MF film samples in this article - scanned @ 4.000 ppi on a film scanner. Using an Imacon X5 or a drum scanner will deliver considerably more detail. For a correct comparison you would need to use at least an Imacon X5 (which is half the price of a Leaf back). In this case the two systems would at least be on par.
    For anyone who is interested in the data: the cut outs or crops in my above mentioned article are exactly 450x300 pixels at 100% from a 11.732x8.690 pixel image - almost the same size as the Leaf image. Download the Leaf JPG, and do some 450x300 crops and compare for yourself.
    Besides this, I can't help if a person like Graham reads my articles without understanding/comprehending and putting them into a false context by citing only parts of it and posting them here for a misleading interpretation.
    Last word: I know and acknowledge that an 80 MP sensor delivers a hell of detail, and I agree that both film and digital are on par for MF. But again, this wasn't the point when Graham started his 10 MP to 35 mm film comparison.
  48. I have sold a 4m wide print (400cm, 157") essentially from a 6x7 film original. Big prints are looked at from longer distance so same level of detail is not needed in posters as in smaller prints, and that makes optimum quality a bit vague concept.
  49. I think we are in danger of spending too much time arguing about resolution as we are probably now at a point where both film and digital users are constrained by the laws of physics.
    It is my view that because of these constraints, for the same sensor/film size, we will get very similar resolution from both.
    There are still some advances which could be made to sensors. Most recent improvements seem to be with low light capability (something which doesn't interest me at all). Perhaps more effort needs to be made to improve the dynamic range.
    I still think that the camera type you want to use is the best one for you and this is much more important than any differences in resolution, etc.
    I used to use a Nikon D100 but went back to film. The quality and resolution of the D100 was plenty for me and I know it has improved greatly since but it is the amount of computer based post processing time which I didn't like. I would rather be in a darkroom.
  50. "[...] as we are probably now at a point where both film and digital users are constrained by the laws of physics."

    Perhaps, yes.
    But it should be pointed out that both are not limited in the same way nor to the same limit.
    For instance, the colour pattern put in front of digital sensors poses a far greater limit than any law of nature imposes on optics and film's capability to capture what optics will allow.
    There are other limits though. Posed by some other laws of nature, perhaps best dubbed the 'laws of pragmatics": when you get what you need, you get what you need. Right?
  51. I had a 6x4.5 neg printed at 1 meter X 1.5 meters (I guess about 40 x 60 inches) and it looks great. It is soft and grainy close up, but from normal viewing distance it's really nice. IMO you can go much larger than many people say you should. Wall size prints don't need 300 dpi - text on a page needs 300 dpi. You can test yourself at A4 to get a feeling for it.
  52. Jens, I've just come in on this and have no "beef" with anyone here, but honestly what you're claiming is just ridiculous. And that sample you've posted just looks blurry as anything to me.
    If we're making silly claims; here's mine. I'm attaching a shot from an 8MP bridge camera (honestly) with about the same area cropped at 100% from the frame. IMHO my crop looks far sharper than yours. Notice the Amnesty International symbol on the young lady's tabard? Let's stop the war right now!
  53. jens,
    I have a question on your resolution article.
    Fuji Velvia 50 resolves 160 lppm [ line pairs per millimeter ], Fuji Provia 100F Professional as well as Kodak EliteChrome resolve around 140 lppm. This is the finest level of detail it can resolve, at which point its MTF [ Modulation Transfer Function ] almost hits zero.​
    How are these tests performed? Do they use a high contrast target like 1000:1?
  54. Let's not go down another track, particularly not one that has a big sign reading "Dead end" in big letters and in plain view at its beginning: high contrast or low contrast does not matter.<br><br>Yes, you lose sight of things sooner when a low contrast is reduced even more than when starting out with a high contrast.<br>But resolution is resolution: the ability to keep two points separate. A matter of point spread size and energy distribution therein.<br><br>And another 'yes': films like the ones mentioned have no problem (in everyday, 'real life' situations) resolving those numbers of lp/mm. There is absolutely no point in trying to contest those. (If you want to have something to niggle about, jump on that "lppm", which has one "p" too many and is one "m" short ;-) ).
  55. And another 'yes': films like the ones mentioned have no problem (in everyday, 'real life' situations) resolving those numbers of lp/mm. There is absolutely no point in trying to contest those.​
    So a 1000:1 contrast ratio is found in everyday, 'real life' situations?
    But resolution is resolution: the ability to keep two points separate.​
    Then why do film manufacturers give lower resolution numbers for lower contrast targets? Isn't resolution resolution?
    Films are resolving those numbers through what lenses?
    What about the lenses in scanners?
  56. Going down that Dead End anyway? Use the net and inform yourself. Those figures are nothing but extremely realistic.<br>And another Dead End? Yes, lenses resolve even more. Even mediocre thingies have no problem matching or surpassing film's capabilities.<br>And a third Dead End: scanners have no problem resolving detail even finer than both film and taking lenses can (re)produce.<br><br>If you (or anyone else) want to fight a battle, pick one that actually is one. The Big Contentious Issue still is (see this thread) whether sensor technology has advanced to the point it can match the lenses that are put in front of sensors (the answer to that still is "not yet") and the film it is replacing (undecided yet, mainly because it depends a lot on what you are looking at, and for).
  57. Why wont you allow Jens to answer? I directed my original question to him. Why is this a dead end?
    He has written several articles addressing this issue so I wanted to ask some questions. Why isn't that allowed? We have a discussion concerning large prints. Why aren't resolution figures part of that discussion?
    Can you point to any film resolution tests that show these film resolution figures to be extremely realistic?
    Why is asking a question tantamount to fighting a battle? It seems to me you are trying to stifle the discussion. Why is that?
  58. "Can you point to any film resolution tests that show these film resolution figures to be extremely realistic?"

    Yes. One that proves to be very useful here on PN: "The resolution of photographic film", Zeiss Camera Lens News, March 23, issue 19, page 6.
    (It used to be available on Zeiss' website, but the publication has been changed into a blog, and the archive no longer contains a working link to that issue. It's too large to post, but i will extract the page and post that later.)

    Asking a question is, of course, not tantamount to fighting a battle. But asking about things that are well known, well established, serves no purpose (hence "Dead End"), except, perhaps, distracting from the real issues (Tactics? Battle?).
    How long do you suppose have we been using lenses and films that we need to establish what they are capable of, now? ;-)
    But when it comes to whether or not digital has caught up, the issue, without fail always turns to what film can do. As if we don't know that... and as if saying that one thing isn't that hot would make another thing, that isn't better, look good.
    But we know what films and lenses can do. What can digital do?

    And before we get entrenched in another Dead End battle: no, i have nothing against digital, am not saying anything about the relative merits of the two media. Just commenting on The Usual Way the issue gets obscured and bogged down by the Seemingly Inevitable Dead End Questions.

    Now, who is not allowing Jens to answer anything???
  59. Marc, the film fanatics can't produce any detailed photos to back up their claims, so they keep referring to those meaningless numbers. Be wary of anyone defending Jens' article or maths - they clearly live in a land where their film is sprinkled with pixie dust to give it a magical 175 megapixel resolution and they can't be reasoned with :p
    Kodak themselves say on their website that "resolution level (2048 x 3072 pixels) captures all the image data 35 mm film has to offer". Ouch, that's 6.3MP.
    Here is a list of tests including real world image tests of film v. digital. They seem to agree with my original assessment that 35mm maxes out in the vicinity of 10MP. By the way, I used to work at one of the largest repro houses in Melbourne in the film heyday and we would never scan a 35mm frame at more than 4000 pixels long (10.6 megapixels), because there was no more useful image information after that point. That was on a top Heidelberg drum scanner.
    Ok, now to some links with real world results:
    Here the author concludes that 35mm film is beaten by an 11 megapixel digital camera:
    Here the tests show that 35mm Provia gives very similar results to a 6MP digital camera:
    Same conclusion here:
    Here the author finds that an 11 megapixel camera beats 67 film:
    Here the author finds that 39 megapixels almost catches up with 4x5 film:
    Shutterbug magazine finds that 6MP digital is approximately equal to 645 film:
    Here are some test results of a variety of film and digital cameras:
    There are hundreds of tests like this out there, all with approximately the same results.
  60. "[...] the issue, without fail always turns to what film can do [...] as if saying that one thing isn't that hot would make another thing, that isn't better, look good."

    "Marc, the film fanatics can't produce any detailed photos to back up their claims, so they keep referring to those meaningless numbers. Be wary of anyone defending Jens' article or maths - they clearly live in a land where their film is sprinkled with pixie dust to give it a magical [...]"


    How very boring. Every time again, the same inane thing...
    Luckily, most people know what they get from whatever medium they use, and use them precisely because they do know what they get from them, be it film, digital or both.
  61. Marc, the film fanatics can't produce any detailed photos to back up their claims, so they keep referring to those meaningless numbers. Be wary of anyone defending Jens' article​
    What about me, a 100% film user, defending your 80MP image and reversing my opinion of it having been able to look at an actual file?
    There are film fanatics who use huge pieces of film - up to 20" x 24". These have more detail than anyone will ever need or ever get from a digital sensor but it's not a competition is it?
  62. Steve, you're right - it's not a competition. I am just trying to correct some false information posted earlier in the thread which several people are still trying to defend. I actually bought 4 rolls of 120 last week and am looking forward to shooting B&W for the first time in years!
  63. I'm not sure where these silly figures for film resolution are coming from, but they certainly don't tie in with my 45+ years experience of using film.
    Someone asked about the methodology used to get these figures, and I can partly answer that: The measurement of resolution figures for film doesn't involve use of a lens. They're either contact printed, directly projected onto the film with a moving slit and lamp arrangement or more likely these days scanned with a laser. However they're produced, they're totally divorced from any means commonly used in real life to capture an image by using a camera.

    I'll attach an extract from a PDF by Zeiss - the company, not some Fanzine using Zeiss in its title.
    As a little background; the MTF curve of film or a digital sensor needs to be multiplied together with that of the lens used to produce a combined system MTF. So, for example, if the two MTF curves hit 30% contrast at the same resolution figure, then the combined contrast would be 30% of 30%, giving 9%. This would take the combined MTF below the accepted perceptual threshold of 10% contrast, and would therefore be seen as the cutoff point of resolution.
    The MTF curves below show the combination of a very good lens working close to the diffraction limit at f/5.6 and what Zeiss considers to be a typical colour film. You can see that the 10% limit is reached at around 80 line pairs per millimetre, which relates closely to my own experience. In pixel terms this would be equivalent to just under 22Mp on a 24 x 36mm frame - a long way short of 175 Mp!
    Remember this data originated with Zeiss, so if anyone wants to argue with it, argue with the big Z.
  64. Thanks for posting that Joe. I would argue that 10% MTF is too low. 30% seems more reasonable, which happens at 50 lp/mm, or an equivalency of 8.6 megapixels. Of course you can argue about where to draw the line and there is no correct answer, and the result will often be lower anyway due to the lens or film not being up to the high standard shown here.
    By the way, your maths wasn't correct. The interaction of MFT works like this - the combined MFT is 1/((1/a)+(1/b)) where a and b are the two individual MFTs. Example: at 60 Lp/mm, the above film has an MFT of 32 and the lens, 70. The combined MFT is 1/((1/32)+(1/70)) = 22%, which is the same result shown by the graph.
    Your example of two MTFs of 30% combining would give an MTF of 15%, not 9%.
  65. In reality, the figures for resolution of sensors or scanners or quality of lenses and film and pictures of test charts mean anything.
    To me, all that is important is the quality of a print. If it looks good, it is good.
  66. I meant: 'don't mean anything'.
  67. R.J.

    If that publication you were calling a fanzine is Camera Lens News: you should know that it is the publication produced by the very same people from the very same Zeiss Camera Lens Division you give thanks for providing the graph. ;-)

    A more serious point though: yes, you can measure film resolution using film only, i.e. without lens. But doing it the way the Camera Lens Division did obviated the theoretical attempts to answer the question what that would mean when we put that film in a camera, put a ens on that camera, and expose the film as we normally would.
    Theory can be fun, but you do have to know when it is helping us to get closer to knowing 'what's up', and when it does the exact opposite.

    So though you say you can "partly answer" what "the methodology used to get these figures" was, you demonstrate that can't. Notice how the people from Zeiss' Camera Lens Division themselves explain how they arrived at those "silly figures", while you put your trust in some theoretical considerations instead! ;-)

    And finally: the length of my experience with film easily match yours, and i can confidently say there's nothing silly about those figures.
    So much for that sort of "evidence". ;-)
  68. Since we're all having so much fun, and nobody's posted an image from a D3x or M9 yet, I just thought I'd chime in with a quick look at the images Q.G. posted.

    The larger (presumably full-frame) image is 450x294.
    The inset rectangle image is 450x300.
    The inside of the red rectangle in the larger frame (and I'm going with the inside to give the maximum estimated resolution) is 17x12 pixels. Obviously the rounding isn't quite right for the aspect ratio, but we'll go with it.
    Pixel peeping at the inset image, I can't see an edge that transitions in fewer than four pixels. That's being extremely generous in my opinion, but I'm sure it can be debated.

    Blown up to the resolution of the inset image, the whole image would be something like 450x450/17 by 294x300/12, or 11912x7350, or 87.6MP. That would tally with a 2x enlarged 4000ppi scan of 37.8mm by 23.3mm, which is a reasonable approximation to full frame.

    Now, I claim that the linear resolution of the inset image, given that each transtion seems to take four pixels, is no more than a quarter of this. In other words, actual detail is something like 5.47 megapixels.

    Now, you can argue that a digital camera with a low pass filter and a bayer sensor can't resolve its nominal pixel count, and that to beat this definitively we need either a camera with four times the resolution (such as a D3x, or - more or less - a 5D2), no filter (such as an M9), or no bayer sensor (SD1). And you can argue whether the lenses are up to it anyway, although it helps that the thickness of the film isn't an issue for a digital sensor. The film grain is also much more visible than any digital noise is likely to be at similar ISO.

    I love film. I shoot film - and digital. But, while I'm still waiting for someone with a high-end digital camera to make the point, I thought it was worth pointing out that the apparent resolution of the example film image isn't all that great. All I can show off is a D700 image (a 161x116 crop scaled up to 450x300, which is the same proportion of the total frame shown in the red box) - this is unsharpened, JPEG from the camera, and simply an example I could find easily, remembering that the D700 is known for having a strong low-pass filter and only has 12MP. Still, I think it's comparable to the film image.
  69. For reference, here's the source image.
  70. "[...] a quick look at the images Q.G. posted."

    Just for the record: i haven't posted images.
  71. Oops - terribly sorry, Q.G. I got confused while multi-tasking. The images I referred to were, of course, Jens's.

    Of course, I should also say that the film image is a much better example, and also a much nicer photo (especially since the latter was a documentary image that I just pulled out as the first thing I could find that was ISO 200 and shot with a macro lens). But that's not the camera's fault. :) I'd say the differences are small (looking at the scratches on the silver on mine, and the detail in the painting on the scan); the film is possibly slightly sharper, but the grain is pretty distracting at this scale.

    Of course, there's a lot more resolution and (relatively) finer grain to be had from medium format film - or 5x4 - and I'm in no position to go shopping for a medium format digital back. So I won't be stopping shooting film any time soon, but nor do I expect my 35mm slides to give a significant improvement in resolution over my DSLR.
  72. If you take the trouble to go to Jens' 3rd link, he shows and gives more details on the same 35mm image and same 200% crop. The important point is that he states that his full 35mm scan is "21 MegaPixel". Now that's way more reasonable than the 87 megapixels scanning that he claims is necessary for 35mm in his 2nd link. And it agrees with the "just under 22Mp" that Rodeo Joe related to us from his extract of Zeiss "best case 35mm" work.
    But the ironic thing is that Jens' image doesn't even come up to "best case 35mm" performance. When I copied the 200% crop from his 21 megapixels scan into my image viewer and examined it up close, I saw that it is clearly oversampled. The sharpest linear features and edges (such as the arch supports in the castle "picture within a picture") have transitions which are 4 pixels wide (the arch supports are double-edged so they are 8-9 pixels wide). I resized the image by 50%, flipped back and forth between the original and 50% version, and all of the same detail was still present, albeit more pixellated of course. I then resized the 50% version by 2x, back up to 100%, the same sampling as the original. This resizing necessitated interpolation of course. The original and resized-from-half-sampling version are stunningly similar - which verifies my original impression that it was oversampled. I will acknowledge that the original was a tiny bit sharper in some of the arch supports. So it's not fully 2x oversampled; I'll be generous and estimate 1.5x oversampled (where 1x means correctly sampled). 1.5x oversampled in both axes means 2.25x too many pixels in area. And 21 megapixels divided by 2.25 is...damn close to the 10 megapixels which Jens was dismissing out of hand!
  73. I will say one more thing - Jens' treatment of Graham in this thread was absolutely appalling. To call him a "Dishonest liar" (he did so in bold font just to make sure that no-one missed it!) shocked me to the core. In my country, that would mean a very large libel payout!
    "An actionable defamatory statement has three ingredients:
    • it must be published,
    • it must refer to the complainant and
    • it must be false."
    Jens' outburst meets all three criteria.
    And it is certainly false. I knew that Graham was being truthful and accurate all along - I am familiar with his professional work and his tools. Troll cartoon aside, he showed more patience than his antagonists deserved, and did the right thing - he came back with more and more evidence to back up his position.
    This being the lawless internet, I have a feeling that Graham won't be looking for trans-national libel payouts: but a public apology from Jens would be in order.
  74. Ray, thanks but I'm not bothered by his accusations when everyone can judge his behaviour and competency for themselves. His 'scanning back' response was an instant fail classic.
    By the way, Jens' blog article which he linked into this thread gets worse - if you keep reading, he asserts that "we would need a digital camera of 87 x 2 = 175 MP to see every last detail compared to film". He and Q.G. are still sticking to this story too [​IMG]
  75. "He and Q.G. are still sticking to this story too "


    That's a libelous contention.

    I never even attached to that story, and certainly am not sticking to it. What i did was point out the silly things that are used (on whatever side of the argument) again and again, and in this thread too, in efforts to make a point and undermine what the opposite side is putting forward.
    You're strong determination to do your best to make your point must have made you blind to that. ;-)

    (Blind rage, painting with broad brushes, an inability to grasp the subtleties of an issue: all (it's one and the same thing, really) part of the range of silly things that happen, without fail, in these sorts of arguments. So no surprise. ;-) )

    Back on topic though: that assertion you plucked of the blog is true, of course. Certainly not about every bit of exposed film, but lacking a mention of how big that bit of film is and how it was exposed, it's a given that there will be a bit of film that makes it true. ;-)
    Subtleties, brushed over because too eager to make a point... A silly point, because it is not ad rem, but no more but an attempt to make someone look bad.
  76. Q.G, if you don't agree with those figures then I am glad to hear it, but you appeared to agree twice with Jens' numbers:
    "films like the ones mentioned have no problem (in everyday, 'real life' situations) resolving those numbers of lp/mm" and

    "the length of my experience with film easily match yours, and i can confidently say there's nothing silly about those figures"
  77. Ray - I agree; I browsed Jens's article, but rather than getting into a debate about what this or that film and lens combination may theoretically be capable of (and I have seen some very high resolution monochrome detail resolved by film), I thought it best to restrict myself to the actual image being shown here. As I said, I agree with you about the 4xoversampling - from Jens's other images, he does seem a bit keen on showing a scan that's got more pixels, but not necessarily more detail, than a digital image (there are some point sampled enlargements that are a little misleading).

    I think it may have been a little misleading of Graham to post a medium format digital image (very nice though it was) in response to a 35mm film scan, without stating up front that this was the source. Still, there'e been a lot of putting words into other people's mouths on this thread (especially the whole 10MP thing); I'm sure it would be better if we made sure we were sticking to the facts.

    Anyhoo. I have no intention of dismissing film, I just wanted to make the point that the image Jens presented is not a mind-blowing example that digital isn't up to snuff.

    As Joe said early on, the issue is not the print size, it's the viewing angle. If you work with the maximum angular resolution that the eye can resolve (I worked from this), I calculated that the eye can resolve the pixels of my D700 when the field of view of a print matches, roughly, a 60mm lens (in good light). It's a 40mm lens for a D3x. I have a 30x20 print that's fine from a normal viewing distance, but since the image was from a 24mm lens, if you view it at the right distance (20") the camera's resolution is clearly not up to snuff. 35mm film wouldn't be either; I keep meaning to get a 35mm (focal length) lens for my Pentax 645 for this kind of image, or just go large format. Hence I'm genuinely interested in the answers on this thread, in addition to the film/digital debate (which I agree has been done to death).

    I'm mildly curious how much resolution-per-film-area drops as film size increases. The increased thickness of 5x4 film makes matching 35mm resolution difficult. The flatness of 120 film may or may not allow it to keep up with 135. The larger formats have more total resolution, but I doubt they're absolutely identical per unit area; after all, 5x4 can get away with f/64 solely because of the larger size.

    The short answer to "how large can I print 6x7 at maximum quality" is: 6x7, because a contact print will have higher resolution than a projection. After that, it's very much a sliding scale.
  78. Graham,<br><br>There are many figures bandied about in this thread. I have no problem believing (as if it would be a case of 'believing') the figures Zeiss provide concerning the resolution films are capable of recording in every day shooting situations. There's nothing strange or controversial about those. On the contrary: they are part of that well-established, broad knowledge base gathered through many decades of using film and witnessing how film progressed.<br><br>How that translates to MP is the issue hotly debated over and over again. Discussions that are quagmires of misunderstood misinformation, partizan 'factoids' and convoluted ways of reasoning, in which terms are often given new, convenient, meanings, and in which inconvenient factoids are ignored. On both sides of the argument.<br><br>In other words: if you wish to think (as you apparently did) that i attached myself to anything Jens (or anyone else) claims, you of course are free to do so. Doesn't make it true. Just illustrates how silly these debates all too often are. ;-)
  79. Graham. Re the maths of combining MTFs. I made no mistake. The product of percentages is exactly how the combined MTF contrast figures are calculated, and give exactly the same results as Zeiss's graph. To use your example: 70% of 32% is 22.4%, (70/100 * 32/100 *100) which coincidentally is almost the same figure as arrived at by your method of 1/(1/32+1/70) = 21.96. However this is a pure coincidence, and if you check the results using your method with other points on the Zeiss graph, you'll find they're at variance.
    Take the 80% (lens) and 52% (film) contrast points at 40 Lp/mm.
    80% of 52% is 41.6%, exactly as shown on Zeiss's graph. Using your method we would get 1/(1/80 + 1/52) = 31.5, which doesn't agree with the graph.
    Again, if we take the two points that are the same for both film and lens at approximately 92% and 17 Lp/mm.
    92% of 92% is 84.64%, which also agrees with Zeiss's graph. But 1/(1/92 + 1/92) = 46. Oops! Sorry, but that's a mile out. And 30% of 30% is indeed 9% , not 15%.
    The full PDF from Zeiss, entitled "How to read MTF curves" is available here.
    The mistake I did make that no-one has picked up on was to use Line pairs per millimetre as the spatial frequency measure, when the standard for MTF graphs should be Cycles per millimetre. But then Zeiss has made the same boo-boo too.
  80. Regarding the question of how large can you print with a given film format, there is an experiment that is fairly easy to help decide how large of a print you can make before moving up to a larger format film would show an improvement.
    Using any format you wish take a photo with one of your sharpest lenses, in my case I use my 50mm, then change to a longer lens and take the same shot, in my case i would use around a 100mm lens. Make a series of print sizes from the photograph taken with the shorter lens and prints that match the scale with he longer lens. For example if I shoot my two photos with a 50mm and 100mm lens then for a 12x18 inch print from the 50mm shot I would make a 6x9 inch print from the shot using the 100mm lens. The result is that the two photos will have the same scale. When you get to a print size where you can see an improvement in the photo taken with the longer lens you are past the limit for the format the photos were taken with.
    Of course the viewing distance you use is going to have a large impact on when you see the differences between the two shots.
    This can all be done with a 35mm format and then scale up the results for larger format.
    My guess is that if you are viewing the print close up that enlarging past around 8x will be produce a print that be noticeably poorer compared to going to a larger format and enlarging less, again viewing the print up close. Clearly the exact number depends on the film, lens and scanner (if use) to make the print.
    Another way to look at this is some people are pretty happy with their 4000 ppi scans for film, but if they took the same shot with a format twice and large and scanned at 2000 ppi scan the larger format scanned at 2000 ppi would look far better.
  81. Joe, the same formula that I posted appears here:
    and here:
    and page 6 of this presentation:
    It also appears in this link, but with a cautionary note which I have quoted below:
    "Several sources use the formula 1/r_final = 1/r_lens + 1/r_film to compute the final resolution. This formula is an approximation to the exact calculation consisting of the convolution of the response of the film and the response of the lens. This approximation is most valid when both the film and lens are being used near their resolution limits (spatial frequencies with very low contrast). This corresponds roughly to f-stops up to f16. Thus the formula is pretty good for 35mm and MF work. However, when the frequencies involved are nowhere near the film limits, the formula is a poor approximation which predits a worse 1/r_final than what you actual get. For f-stops of f32 and higher, what you get on film is in fact practically equal to the aerial resolution, and the formula shouldn't be used in that case."
    Norman Koren writes:
    "The response of a component or system to a signal in time or space can be calculated by the following procedure.
    1. Convert the signal into frequency domain using a mathematical operation known as the Fourier transform, which is fast and easy to perform on modern computers using the FFT ( Fast Fourier Transform) algorithm. The result of the transform is called the frequency components or FFT of the signal. Images differ from time functions like sound in that they are two dimensional. Film has the same MTF in any direction, but not lenses.
    2. Multiply the frequency components of the signal by the frequency response (or MTF) of the component or system.
    3. Inverse transform the signal back into time or spatial domain."
    This isn't very clear to me so I'll have to look into it further.
  82. Graham. In those links you gave the addition of reciprocals is being used to add resolution figures, not MTF contrasts. An MTF curve can be used to find the limit to resolution, in cycles/millimetre (or more crudely lp/mm) of a system or individually of a film, lens, sensor or scanner say, but resolution is only one axis of the MTF curve.
    So if we define the limit to resolution of the film in Zeiss's graph as 40% contrast (a bit high, but the lens contrast is only shown to just under 40%), and the limit of the lens as 40% as well, we can see that the respective resolution figures are 50 and 140 lp/mm. Now we plug these resolution figures into your addition-of-reciprocals formula and we get 1/(1/140 + 1/50) = 36.84, which isn't too far away from the real resultant of 42 lp/mm at 40% contrast as shown on the graph.
    So, in the absense of full MTF data, and if we only have resolution figures to work with, the addition of reciprocals gives a reasonable approximation to the system resolution. But it's still an approximation, and no matter how many times it's been repeated, and with what authority, it still isn't the proper way to go about things. And you can clearly check with Zeiss's graph that adding contrast figures using that method gives completely the wrong result.
    If you think about it, the product of percentage contrast makes absolute sense. If one component of the system reduces the contrast to half (50%) and another component reduces the contrast to one-quarter (25%), then the resultant contrast must be half of one-quarter, which is one-eighth, or 12.5%. Using the addition of reciprocals we'd get 1/(1/50 + 1/25) = 16.67.
    Sorry Graham, but more than almost any other field of study, photography has a store of perceived "wisdom" that turns out to be based on almost no evidence, and most of what we think we know is wrong! Such as film being an analogue medium for example, or 140 line-pairs per millimetre being achievable on 35mm film with off-the-shelf equipment.
  83. In a nutshell, Graham used the right (approximate) formula, but applied it to the y-axis values of the MTF graph instead of the x-axis values. A very understandable slip, since the y and x values often lie in the same numerical range (e.g. 0-100%, 0-100 lp/mm).
  84. Yes, thanks Joe for the correction!
  85. Apologies for the long-windedness of the above. I was trying to give a full explanation and got a bit carried away. Note to self - KISS!

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