Film Latitude vs Digital Cameras

[sigmar_pietsch]

Can anyone tell me how and if "film Latitude" equates to Digital Cameras.

Example, the old Tri-X has a latitude of 9 stops, Plus-X has 7. Does film

latitude in some way translate over to digital? Or differently, when Canon

built the EOS 40D and you shoot in b/w, is it designed to work like Tri-X? Like

what b/w film. Any ideas? Thanks for your time.

[conrad_hoffman]

Once you saturate a digital sensor with too much light, that's it. There's nothing much there to recover. OTOH, you can overexpose film substantially, and there will almost always be something buried in that density that you can bring out. A digital camera is more like slide film. Overexpose a slide and there's nothing there but clear film. It doesn't matter if you put it in b&w mode, and I don't know why anyone would do that anyway. If you want b&w, convert later. So, film almost always has more latitude than digital, but you can also pull more useful information out of the shadows (along with noise) with the digital. In either case it pays to meter scene brightness range and plan accordingly.

[danielleetaylor]

I've put a lot of B&W film through my film body the past 3 months for a class in traditional B&W developing and printing. And I've been shooting my 10D side-by-side to learn how they compare and how to best achieve the "film look" using the digital.

 

I was surprised to find that the dynamic range (or latitude) was very, very close. The difference is not in the total available range from black to white, but in where more of that range exists.

 

B&W film has more range in the highlights and less in the shadows. So if the total scene brightness is less than the available dynamic range of the film, you have more room to overexpose and still recover all your detail than you do if you underexpose.

 

Digital is the opposite. You have more room to recover with an underexposure than with an overexposure.

 

So with digital you need to meter and expose to keep the highlights from blowing and let the shadows fall where they may. You can generally recover the shadow detail later, but if you blow the highlights they're most likely gone. (RAW gives you about 1 stop of recovery on the highlight end.)

 

With film you have to make sure you get enough exposure for the shadow detail you want, and let the highlights fall where they may. If you underexpose, the image will quickly become a grainy, blotchy mess.

 

You have to adjust this advice for a scene with a greater dynamic range than your DSLR or film can record. In that case you need to decide what you want to keep and what you want to throw away, and meter/expose accordingly.

 

If you meter and expose optimally for each, you will get very similar total dynamic range.

 

You don't want to use a B&W mode on the camera. Save the color information for use when converting later in post processing. That information can help you shape the tonality of the image the way you want, the way a traditional B&W photographer would shape the image with color filters.

[stwrtertbsratbs5]

I shoot B&W film because I enjoy darkroom work and because I like the results. Film is just different from digital. I've seen great results from both. But, for me, B&W ink jet prints aren't as nice as silver gelatin prints. Simply a matter of personal preference, though.

[matt_needham]

The issue with over-exposing digital isn't just a problem with digital as much as it's a problem with positive exposure systems; slide film has the same problem with over-exposure. Negative film has the same issue on the other end; under-expose it and shadow detail is lost forever. With film you've got to watch out for zero density; with digital you have to watch out for tone #255.

 

In my own experience with DSLRs shooting raw they have much more dynamic range than slide film, and a little more than most neg films. Although some folks are squeezing out 10+ stops doing their own BW film processing.

 

One thing that has really changed for me switching from BW film to digital (BW and color)is that the incredible control and precision that is available in digital processing allows me to use techniques to extend the dynamic range that I couldn't do (or wouldn't be likely to use) in my traditional BW darkroom. It's very easy to blend or combine multiple exposures in a variety of ways that give almost unlimited dynamic range.

 

Here are some articles about digital dynamic range compared to film written by people who have more time and interest in testing than I have.

 

http://www.clarkvision.com/imagedetail/dynamicrange2/index.html

 

http://www.normankoren.com/digital_tonality.html

 

http://www.ronbigelow.com/articles/dynamic-range-1/dynamic-range-1.htm

[danielleetaylor]

Robert,

 

At least for Fuji Acros on Ilford MGIV Glossy, I have a couple sets of prints (darkroom, film scan to ink jet, DSLR to ink jet) where you wouldn't be able to tell me which was which. It did take some work to match the digital B&W conversion to Acros, but it was doable.

 

Though I must admit I find the darkroom relaxing.

 

I don't know if I could match what I did today with a DSLR though. Kodak HIE printed using one contrast filter, then part of the image (sky) heavily burned using a different contrast filter. It came out pretty cool. The problem on the digital end would be matching HIE's response. I'm not sure how close a DSLR modified for IR photography comes to Kodak HIE.

 

Alas, Kodak HIE is discontinued, and I doubt I can even find another roll. The store I bought this last roll from was limiting purchases to one per customer, and they were almost out :-( With other discontinued films there have always been close substitutes. I'm really bummed about losing Kodak HIE though.

[rustys pics]

Daniel, check out Efke IR 820c film. Very slow, but similar to HIE with a Hoya R72 filter.

 

DSLR and B&W film are apples and oranges. I think silver still has an edge in B&W. The digital B&W I see makes skin have a bizarre plastic look. Best thing to do is shoot some black and white film. Make some analog prints, as scanning is really not a good way to get film to look like film.

[michaelchristensen]

I'm no expert on counting steps of latitude, but the so-called experts are usually unanamous on this issue .. that film has greater latitude than film .. it seems Fuji is conviced of it and Nikon and Canon are in constant debate as to which digital camera approaches the latitude of film .. hence, film is king on this one topic.

 

Funny thing is that you talk to strictly digital photographers today and they seem to have forgotten what a good black and white print looks like .. and they waste a lot of time and energy attempting to make that digital sensor do what film has already nailed with a hell of a lot less effort..

 

Every generation of digital camera claims to have a more film-like look for skin tones and greater exposure latitude .. I've been listening patiently to the likes of Fuji, Nikon and Canon for the last 5 years .. in fact, I've heard this nonsense from the time the top end camera was 4mp, then 6, 8, 10, and now 12! Now we hear that the Bayer pattern may not be condusive to the tonality that photographer need .. well, they are right about that ..

 

don't misunderstand, I love my d200 and like photos I've seen from Fuji S2-5 cameras .. I'm glad they are expending so much effort to do this, but c'mon guys .. a simple pro-roll of film is $5 .. and that S5 -- well I've lost count of the pennies needed.

 

Bottom Line answer from every major digital reviewing website is No, digital does not have the same latitude as film .. and if I hear the photosite light well argument one more time it's gonna make my head spin .. (laugh) .. you want latitude, shoot film ..that was easy.

[danielleetaylor]

Russ,

 

I'll have to try Efke IR 820c as a HIE replacement. It is really slow, but I'm interested in landscape IR shots any way. Thanks for the suggestion!

 

I'm not sure if your second paragraph was directed at me, but if it was: the sets of prints I'm referring to (which I made) each include one analog darkroom print from B&W film (Acros); one ink jet print from a film scan of the same frame used in the darkroom; and one ink jet print of a DSLR shot of the same scene, made as close as possible to the film shot both in terms of composition on the scene and tonality when converted to B&W.

 

There's nothing to give them away as having been produced by different methods.

 

The two hurdles I had to overcome were making the ink jet prints look neutral, and matching the DSLR tonality to Acros. The first was solved with QuadToneRip, which I can't recommend highly enough. The second took some playing around with each image.

 

One of my goals in taking a B&W developing/printing class was to get a better feel for how traditional B&W materials render different scenes, then try to match with digital. I'm going to continue with that "study", if you will, and broaden my use of films and papers in the new year. I want to do enough conversions with a traditional print as a reference that I'm able to sit down with a digital image and no reference and still shape the image to have a "traditional" B&W look.

[colinsouthern]

Film: Expose for the shadows, develop for the highlights.

 

Digital: Expose for the highlights, "develop" for the shadows.

[sigmar_pietsch]

Dear All, Thank you vm to all of you for your answers. Specific thanks for the web sites listed and to Daniel for the experimental information. In case someone is interested - I called Canon and they told me that the EOS 40D has an approximate latitude of 1/2 stop for JPEG and a bit more for RAW, maybe one stop for any camera setting. I will do some experimenting as well with my old and trusty Canon A2 alongside the 40D. Again, thanks for all your help and information.

Best - Sigmar

[mark_l3]

anyone using the zone system should be getting 11 stops from black to white. and with developer manipulation you can easily get 15 stops.

[danielleetaylor]

Sigmar,

 

That is a really weird answer from Canon. 1/2 stop is obviously not the total DR, or the 40D would record monochromatic scenes (only pure black and pure white).

 

Perhaps they were implying you could overexpose by 1/2 stop and still get an acceptable image? That seems weird to, because your latitude (in that sense) depends on the total scene brightness in relation to the total DR of the device or film recording the image. Depending on the scene, you might have 3 stops of latitude or no latitude at all. Plus I've never seen a JPEG where you could recover any blown highlight detail. In JPEG if it's gone, it's gone.

 

Oh well, the best thing for you to do is experiment with your cameras side by side, as you mention. Be sure to bracket at first. You'll soon see that the best exposure on one is not the best on the other, and it's important to bias your exposure correct to maximize DR.

[sigmar_pietsch]

Daniel,

 

Correct. For example, Fujichrome Velvia 100. I shoot lots of slides and mostly use that film. It has a latitude of +/- 1/2 stop. By latitude I refer to the range of light intensity a film can reproduce or in other words that range of stops from darkest shadows to highlights a film can handle, or in other words, Plus-X for example can handle 5 stops overexposure and still show details, yet only 2 stops of underexposure. Of course you know all this. I am just babbling. Sorry. I will do the same as you - experiment. If you ever find out more, let me know. Thanks a bunch.

Sigmar

[david_henderson]

Sigmar

 

You are confusing dynamic range with latitude, and I think misunderstanding the information you are being given. The range of light intensity (brightness) that a film can record is dynamic range. It is quite impossible for a film to have a dynamic range of +/- o.5 stop and still be remotely useful. Velvia 100 has a dynamic range of about 4 stops.

 

Latitude refers to an inexact concept whereby one can get a usable image whilst not exposing at the optimum. It's inexact because "optimum exposure" is subjective. Also because "latitude" relates to the relationship between scene brightness and the dynamic range of your medium. For example if your film's dynamic range is four stops and scene brightness is also four stops then there is only one exposure that will keep detail in both highlight and shadow and in effect your latitude is zero.

 

I agree with the comments made by Mr Taylor above , and you say you do too- but then you go on to say something completely different and contradictory. The concept of dynamic range is relevent to digital photography anfd film. A DSLR will tend to have a wider dynamic range than nearly all slide film- and notably more than the film you use.

 

I would forget about latitude. Its not a terribly useful concept in absolute terms. You just need to remember that when you're using a medium with limited dynamic range- like Velvia, its much more important to nail the exposure and to carry the means to alter scene brightness range-such as grads or fill flash.