Exposure latitude in film

[A miller]

Advertisement (gone after registration)

Can people share their knowledge and experience with how much exposure latitude there is in black and white film, and which BW films offer more latitude and which offer less?

 

For example, i read somewhere that Ilford FP4 125 has an exposure latitude of 6 stops over and 2 stops under. True? I also heard that the ilford Delta series has substantially less latitude.

 

I am an idiot on this but it seems hugely important as a practical matter b/c it will cause me to not to overanalyze my exposure so much and allow me to be more nimble on the streets.

 

Thanks in advance for sharing your knowledge and wisdom!

 

Adam

[spydrxx]

I'd encourage you to really not think much about exposure latitude and concentrate on securing proper exposure. Your comments above sort of suggest you're considerting thinking about exposure latitude as one thinks about "auto ISO" in digital photography. It isn't the same. When one steps outside of the general parameters the manufacturer has built into film, things like graininess, contrast, and ability to print from the film on normal grades of paper suffer.

[bill]

Best latitude in mono films is to be found in the chromogenics, Ilford XP2 and Kodak 400CN. I use the latter exclusively in my IID and M2. It takes a lot to grt an unusable neg.

 

Regards,

 

Bill

 

Sent from another Galaxy

[250swb]

I would say FP4 will do maybe 4 stops over and 1 stop under. It is easier to accidentally get thin shadows without detail than it is to blow the highlights if your meter readings are roughly in the ballpark when shooting quickly and instinctively.

 

But ultimately it all depends on the contrast range of the scene. Sometimes you need to exposure for the shadows and compensate in the development for the highlights being over exposed, and sometimes you need to compensate for the shadows being under exposed when you wanted to meter for more detail in the highlights. Knowing how to adjust the exposure and development is part of experience, if you process your own film. If you don't process your own Bill's suggestion is the way to go, use XP2. In either case though unless you have a good workflow planned ahead of time the 'T' grain films like Delta are very critical about exposure and you need either the dedicated developers, or as in my case use catechol or pyro based developers.

 

No matter how experienced you are it is always possible to get the exposure wrong from time to time with a manual camera, but if you keep on top of making meter readings and adjusting the camera as the light changes before long you will be able to guess the exposure without a meter.

 

Steve

[xalo]

While I'd agree that proper exposure is important, I also know that I missed moments because I tried to get that half stop sorted out while the scene disintegrated in front of the lens. Clearly I'd have preferred capturing those moments somewhat too bright or to dark, rather than not at all. Also, "proper exposure" is very elusive (thinking once more of R. Frank's jukebox).

Anyway, with b&w negative film and for a hybrid workflow involving scanning my rule of thumb is that I get a good chance to record a scene with most to all retrievable detail when sticking within a stop of the dialed in film speed. Usually I take a measure of a darker part of the surrounding, so as to ensure that I will have some details in the shadows (avoid too much blank film base... exceptions confirm the rule). From then on, I adjust one way or the other in case of major changes of light or scene — sometimes too much or too long, see above.

Having taken on to developing again recently, I particularly notice that most of the 36+ frames are not so problematic because of their various technical deficiencies, but because they are void of meaningful or readable content...

Bref, yes, auto-iso film is not (strangely I had bad experience in particular with FP4 at the seaside), but you have some leeway. Prioritize the subject before minor adjustments. I think even Delta 100 (though I used Acros in this range) will be salvageable if you're a stop or so off. I'd try a more gentle, lower contrast development in those cases.

Cheers,

Alexander

 

P.S.: Just saw Steve's more discerning note. Anyway, my 2 cts.

[A miller]

Wow, such helpful insights from each of you! I really appreciate it! I am asking not because I intend to significantly change my workflow but precisely for the reason that Alexander cited in his first sentence. I all too often miss a moment b/c I am hung up over a half of a stop, or even a stop. The precisely spot-on exposure of an image as one walks the streets can change from second to second, esp on a sunny day in the city with all the shadows. It just can't be that the great streetphotographers in hisory were all so meticulous about their exposure. In fact, the more I learn about this concept of exposure latitude, the more it makes sense to me that the Bresson's of the world were/are less finiky when shooting those "decicive moment" shots (although I'm sure Bresson was meticulous when shooting his portraits.)

 

I don't make changes to exposure thru printing but rather make gaint TIFF files thru scanning with my Nikon coolscan 9000. I have found that elasticity of the digitized files to be greater than my M9 raw files. I think that I am finally understanding why.

 

I tend to slight overexpose my shots by a half stop to better be able to caputre underexposued areas. I find this fairly effective.

 

Is it safe to assume that Tri-X also has a wide latitude given how much it is used in street photography?

[chris_livsey]

Advertisement (gone after registration)

Look at it this way:-

 

Your film has the ability to record 10 stops of "data" from darkest to lightest.

 

A) You want to record a scene on a dull overcast day with limited tones say 4 stops from the lightest to the darkest = plenty of room to make an exposure that will work. Your film has good latitude.

 

You have a classic sunny 16 day, full sun and your subject has full shade and full sun in it = you will be lucky, even if you precisely place the middle exposure spot in the middle of the films range, to record both shadows, with detail, and highlights, with detail, at all. Your film has no latitude.

That is the same film.

 

Conclusion: latitude depends not only on the film ( slide film cannot record the 10 stops so has less inherent latitude than the above BW film in example A) but also on the scene recorded, so in B your film has no latitude even though it is the same film

 

It usually quoted that BW film has more latitude, that is because it has the ability to record a larger range of stops. The measure of how much is usually related to the characteristic curve where the longer the "straight" section (in quotes as some have no straight section actually it is a curve) the more latitude but complicated by some films having a long toe and/or shoulder which give extended range so detail (data) is recorded at the extremes (unlike digital). Some films, usually the T grain like T-Max, have a very abrupt shoulder so highlights suddenly drop off being recorded at all (much like digital). They do retain good latitude because the "straight" section ( and in these films it is usually very straight (( I know, like pregnancy it is straight or not)) is long.

 

Interesting you quote HCB, if you study his classic street work you will find he frequently shoots on the dull overcast days, I wonder why

[A miller]

Thanks, Chris. This is very interesting and informative. I really appreciate your time!

[chris_livsey]

[quote=A miller;2417792

 

I tend to slight overexpose my shots by a half stop to better be able to caputre underexposued areas. I find this fairly effective.

 

Just re-read your post.

 

This was/is the classic approach. Expose for the shadows, you can't print what is not there, develop for the highlights, usually means in high contrast reduce development, it is hard (in film) to blow the highlights totally, unless you use T-grain ,

 

Don't get too hung up on exposure, try shooting without a meter, sunny 16 rule, you will be surprised how little you get so wrong you can't use it.

[A miller]

Just re-read your post.

 

This was/is the classic approach. Expose for the shadows, you can't print what is not there, develop for the highlights, usually means in high contrast reduce development, it is hard (in film) to blow the highlights totally, unless you use T-grain ,

 

Don't get too hung up on exposure, try shooting without a meter, sunny 16 rule, you will be surprised how little you get so wrong you can't use it.

 

Hi Chris - many thanks for your last post. I do indeed try to keep my VC II meter in my pocket and try not to rely on it so much when I'm out with my IIIg and M3. But it is my nature to try to perfect the technique as best as I can at the outset with the expectation that over time I will loosen up and take a more pragmatic approach.

 

I remember years ago when I was learning how to drive, I would make sure that I could succeed at doing exactly what the driving school instructor told me, which involved using two hands to turn, stay dead center in the middle of the lane when turning and to staying within the proverbial bubble while driving on the highway.

 

I got all that perfect; and as soon as I got my bearings on the road, began driving with at most one hand, entering other people's bubbles as the contexts requires and turning in anyway possible within the limits of not leaving my lane.

 

No accidents, a few tickets here and there, and otherwise I get where I need to go faster than most people, and all in one piece.

 

I figure that's where I'll eventually end up with my film cameras when shooting in the streets....

[250swb]

I got all that perfect; and as soon as I got my bearings on the road, began driving with at most one hand, entering other people's bubbles as the contexts requires and turning in anyway possible within the limits of not leaving my lane.

 

No accidents, a few tickets here and there, and otherwise I get where I need to go faster than most people, and all in one piece.

 

I figure that's where I'll eventually end up with my film cameras when shooting in the streets....

 

Personally, as somebody who has raced cars in competition, I think you should consider very seriously the possibility that you are fxxking around with other people's lives when you drive like that on the public road, which makes over or under exposing a frame of film somewhat pathetic as an analogy.

 

However under or over exposure can be used creatively, if you are aware of the implications..... For instance photographers such as Trent Parke or Ralph Gibson intentionally over expose and over develop their films to create the image they have in their head. It is just as controllable as making a so called 'correct' exposure, you just know beforehand what you are aiming for. So don't think it is any less manly to use a meter if needed, photography is as much about working with facts as driving a car safely but fast, you don't turn up at a fast corner without both hands on the wheel and a plan.

 

Steve

[A miller]

Hey Mario - please lighten up. Of course I was exaggerating to make a point. Being called "pathetic" wasn't what I was soliciting in my comment or my thread. Your substantive comment to the initial question posed in my thread was just as judgmental. I don't know where you get off being so judgmental, but I asked an objective technical question that would be fairly straightforward to an experienced film photographer. I didn't ask to be judged as it relates to how technical I should be when I shoot and how reliant I should be on my meter.

 

I appreciate all the feedback, including the judgmental ones (and have sincerely taken them all to heart); but when the responses turn insulting it really crosses the line with me and I'd submit violates forum etiquette.

 

GEEZ!!

[250swb]

At any one time judgement is what some people have and others don't, that is the point of them asking questions. People can learn judgement, some find it difficult, and some never ever have an ounce of it. Some even unlearn judgement. So thank you.

 

Photographically the point about having judgement is that you work with facts, and by working with facts you increase repeatability and reduce the possibility of accidents where no cause is apparent. Creativity comes with using those facts, alongside the skill to 'see'. The recent trend in Lomo photography has shown that while spectacular results can be had from pure accident ( other than the photographer having the judgement to point the camera in the right direction) they do mostly go on to try and find out how to repeat their results. So relying on the wide latitude of a good B&W film to avoid making a decision, a judgement, is often ultimately a dead end. It may make one or two great pictures on a random basis, but even ten stops exposure range won't reliably translate into the photographers overall vision. Intervention is needed, like a plan, to stop photographic accidents spoiling what might otherwise be a great picture. There is no easy way even if rules can be bent or tied into knots.

 

Steve

[philipus]

Aaaanyway, trying to stay on-topic, a well exposed frame is more important than the latitude, particularly for scanning.

 

Naturally, with a hybrid workflow, it is possible to enjoy the benefits of digital post-processing, including multiple processing of the same TIFF, for instance one instance for shadows and one for highlights. It's easy to do. Here's a photo.net article by Harold Miller.

 

Also, if you're developing yourself you could try stand development. Here's an interesting article about it.

 

Cheers

Philip

[Tonki-M]

quoted from Leica M6 manual:

 

THE THREE GOLDEN RULES

1. expose colour slide films for the highlights, and let the shadows fall where they may.

2. expose colour negative films for important middle-tone areas, and never fear over exposure

3. expose b&w films for the shadows, and develop for the highlights

 

some film has more latitude towards highlight, some hold details in the shadow better, some has very good graduation in the midtones. it is best to use one for a while until you get some idea of how highlight and shadow behaves at 'proper' exposure.

[kdriceman]

Aaaanyway, trying to stay on-topic, a well exposed frame is more important than the latitude, particularly for scanning.

 

Naturally, with a hybrid workflow, it is possible to enjoy the benefits of digital post-processing, including multiple processing of the same TIFF, for instance one instance for shadows and one for highlights. It's easy to do. Here's a photo.net article by Harold Miller.

 

Also, if you're developing yourself you could try stand development. Here's an interesting article about it.

 

Cheers

Philip

 

Thanks Philip. Good article.

[A miller]

+1 Really appreciate everyone's insights.

[AlanG]

I always try to keep at least one knee on the wheel.

 

Plus X was a double coated film that could tolerate a lot of over exposure. You really would have to test your film to determine your personal standards. And the brightness range of the scene would be a big factor. Color slide film has very little latitude although you can make some adjustments when scanning or duping. And of course color negative film has some latitude but may lose color accuracy.

 

BTW the stripes on the underexposed images are from my scanner.

Welcome, dear visitor! As registered member you'd see an image here…

Simply register for free here – We are always happy to welcome new members!

[A miller]

Alan - thanks very much for your time. This was very helpful. Best, adam

[Advertisement]

Hallo,

Look here: Interesting Leica gear

[250swb]

A nice illustration Alan, but if the negatives are going to be scanned you need to factor in the latitude of the scanner and software. And while a traditional sheet of paper may have a greater DR than the best scanner, the software can selectively change all the tones in between so even your 4 or 6 stop under exposed examples may become 'acceptable'.

 

If looking to exploit the latitude of a good film it is definitely geared one way, that of controlling over exposure, not under exposure (within limits). On the basis that you can't scan, manipulate, or print what isn't there (highlight or shadow) it is the highlight end of the scale that presents the bigger problem as much less can be done in developing the film to control the over development of highlights, while many more things can be done to bring up shadows. So the 'wide latitude' of film is a bit of a myth in this context. Ten or so stops becomes two or three stops to play with if the DR of the scene is very wide and the camera is loosely set to expose well towards the shadows in the laid back scenario envisaged. So to get anything like consistency the laws of chance have to be weighed in favour of under exposing all the time, not assuming it is a 10 stop range (or whatever) all the time. This will result in a lot of thin negatives at first, but if consistently done this can be compensated for in development to make them better. The only time you can use a 10 stop range is to have metered for it and developed accordingly, otherwise the latitude rapidly trails off.

 

Steve