Question about film development and contrast

[monochromeFan]

page 12 in the section titled lighting states

When processing a film exposed in oveercast conditions, you can increase developement time by about 20% to boost contrast a little. You can make negatives exposed in brilliant sunlight easier to print by over exposing the film half a stop or so, and cutting development by about 20%.

Subject matter

You may occasionally wish to increase development time a little if your subject is very low in contrast. The reverse however is not true: high contrast subjects rarely require any special treatment unless the lighting also creates deep shadows.


is this completely accurate, or are these two sections cancelling themselves out?

[Doremus Scudder]

This is accurate, but not very precise. The Zone System is a lot more precise: you measure the scene contrast and then find a specific development time (which you've tested out in advance) for the contrast conditions in that particular scene.

I think where you are getting confused is with the "overcast" conditions. Subjects under overcast skies, but without the sky in the image are low-contrast subjects; there are no areas lit and shadowed by direct light. On the other hand, on day with bright overcast where you have a scene with the sky in it, the sky can be quite bright. The problem here is that the rest of the scene is low-contrast. Bright overcast landscapes are often a challenge.

Also, as mentioned before, if you shoot roll film, you may want to simply find one good "normal" development time that places negatives of normal-contrast scenes in the middle of the contrast range of the printing paper you are using (say #2-#3 filtration with VC papers) and deal with needed increases or decreases of contrast by changing paper contrast.

If you really feel the need to tweak development times, then learn the Zone System well, how to place shadows, meter highlights and then establish film-developing times for the different scenarios you encounter. Most roll-film users don't bother with this, however. Nor do I recommend it, especially when just starting out.

From your other posts, I assume you are applying the Zone III shadow-placement technique from the Zone System. That will get you well-exposed negatives. The next step is to meter highlights and identify scenes that are "normal" (textured whites "fall" in Zone VIII - five stops away from Zone III). Make negatives of these scenes. Develop and print them with a #2.5 filter. Tweak development time until most of your "normal" scenes print well in the #2 to #3 filtration range. Then leave it at that for a while. You can use the higher and lower contrast filters for scenes that need them.

Best,

Doremus

[Vaughan]

increase developement time by about 20% to boost contrast a little... \over exposing the film half a stop or so, and cutting development by about 20%

This is the foundation of the Zone System when applied to controlling the photographic process from visualisation to finished print. Precision (as @Doremus so elegantly put it) is needed to know how much to change exposure and how much to change development to achieve the desired results.

These days IMHO the end result is NOT a finished print so expansion and contraction of negative density is not necessary, and better results can be obtained by manipulating the scanned digital image in the editor of your choice.

[monochromeFan]

This is accurate, but not very precise. The Zone System is a lot more precise: you measure the scene contrast and then find a specific development time (which you've tested out in advance) for the contrast conditions in that particular scene.

I think where you are getting confused is with the "overcast" conditions. Subjects under overcast skies, but without the sky in the image are low-contrast subjects; there are no areas lit and shadowed by direct light. On the other hand, on day with bright overcast where you have a scene with the sky in it, the sky can be quite bright. The problem here is that the rest of the scene is low-contrast. Bright overcast landscapes are often a challenge.

Also, as mentioned before, if you shoot roll film, you may want to simply find one good "normal" development time that places negatives of normal-contrast scenes in the middle of the contrast range of the printing paper you are using (say #2-#3 filtration with VC papers) and deal with needed increases or decreases of contrast by changing paper contrast.

If you really feel the need to tweak development times, then learn the Zone System well, how to place shadows, meter highlights and then establish film-developing times for the different scenarios you encounter. Most roll-film users don't bother with this, however. Nor do I recommend it, especially when just starting out.

From your other posts, I assume you are applying the Zone III shadow-placement technique from the Zone System. That will get you well-exposed negatives. The next step is to meter highlights and identify scenes that are "normal" (textured whites "fall" in Zone VIII - five stops away from Zone III). Make negatives of these scenes. Develop and print them with a #2.5 filter. Tweak development time until most of your "normal" scenes print well in the #2 to #3 filtration range. Then leave it at that for a while. You can use the higher and lower contrast filters for scenes that need them.

Best,

Doremus

Thats what im trying to achieve, decent negatives that tend to fall within a contrast filter range of grade 2 or 3. I HAVE had the problem of the dull, gray skyless over cast day, adn the over cast day with visible sky. And bright sunlight.

Ive had an unfun road with making prints, and i had to spend a good deal of time deducing what things to change to get improvements.. And at this time the only things left to try changing are improving my negatives, changing my paper without going into the poor house, and figuring out the right way to use a set of hand held multigrade filters.

[Tim Meisburger]

Thats what im trying to achieve, decent negatives that tend to fall within a contrast filter range of grade 2 or 3. I HAVE had the problem of the dull, gray skyless over cast day, adn the over cast day with visible sky. And bright sunlight.

Ive had an unfun road with making prints, and i had to spend a good deal of time deducing what things to change to get improvements.. And at this time the only things left to try changing are improving my negatives, changing my paper without going into the poor house, and figuring out the right way to use a set of hand held multigrade filters.

What kind of enlarger are you using that doesn't have a tray for filters? I use an Intrepid light source on a crown graphic that has filtration built in, but when I used to use the ancient graflarger (made before multigrade paper), I made a wire rack that hung from the standard under the lens to hold filters, and that worked fine.

Are you using old paper? I have used a lot of it, and it can be difficult to get good prints from really old paper.

Have you checked that your darkroom is dark, and safelight safe? If not, you could be getting fogging that lowers contrast.

The zone system is usually explained in a weirdly complicated way. Let me see if I can make it clearer (probably not). The human eye can see tones from brilliant white to absolute black. At the beach we can see tones in the white sand under the hot sun, and the texture of a towel in the deep shade under a beach umbrella. Paper (and film) doesn't see that well; it can only record tones from almost white to almost black, so in a print the beach becomes textureless white and the towel featureless black. The paper can only see the middle tones.

Imagine we have divided the spectrum from pure white to pure black into eleven tones (called zones), but our film or paper can only see five. In a contrasty scene, you want to darken the highlights slightly to push them down into the readable range of the film so we can get some detail, a process called contraction. In a flat scene you might only have a three zone range, so to get more contrast we want to make the darks a little darker the the highlights a little brighter to use to the full five zones we have available, a process called expansion.

The zone system asks you to evaluate a scene to determine if the contrast range. If it is greater than the recording ability of the film or paper, we contract. If it is less, we expand.

Most people these days do contrast control with filters, rather than modifying development, but no matter what you need to ensure you have sufficient exposure so there is detail in the shadows to modify.

Not sure if that helps.

[esearing]

I am assuming you are using a 4x5 or larger camera.

Buy yourself a stouffers step wedge with at least 20 1/2 steps, or a target that has multiple tones. Put the wedge in front of your film in a holder and defocus on a white sheet of cardboard on a sunny day. Meter the cardboard and open 5 stops. or meter the target zone 5 tone and open 5 stops. Repeat for 4 or 5 negatives. Develop the negatives in your standard developer one at a time starting with "normal". You should get a good idea of how many of those zones from the wedge appear on your film. Now adjust your time + and - 20% (or 15%) and see how those tones change on the next 2 pieces of film. And if you have film left you can alter your time by more or less to see the impacts. You can do the same with a scene that has 6 or 7 stops if you don't want to work with the step wedge. Until you do this kind of testing you will not fully understand how your film reacts to time changes during development.

You can then explore the effect of dilution and time for scenes with many stops of light to see if your developer provides the contraction of the brightest tones while still maintaining shadow detail. Waterfalls on a bright day are excellent candidates for this test. Expose for dark wet rocks on zone 3 and let the bright white water and or sky fall on zone 9 or 10. The test is to see if you can pull down those bright spots so they print with a hint of gray and detail.

[Mark J]

defocus on a white sheet of cardboard on a sunny day

To be more specific, the lens should be set up for infinity focus, so that the f/numbers are correct as marked on the lens.
Hence you just point it at the card without refocusing.

[paulbarden]

Thats what im trying to achieve, decent negatives that tend to fall within a contrast filter range of grade 2 or 3. I HAVE had the problem of the dull, gray skyless over cast day, adn the over cast day with visible sky. And bright sunlight.

Ive had an unfun road with making prints, and i had to spend a good deal of time deducing what things to change to get improvements.. And at this time the only things left to try changing are improving my negatives, changing my paper without going into the poor house, and figuring out the right way to use a set of hand held multigrade filters.

Are you using any published books on the subject? You should consider it. Henry Horenstein's "Beyond Basic Photography: A Technical Manual " is a very good resource. Since you are already scratching at the surface of Zone System principles, maybe get a copy of Ansel's "The Negative" and get some proper education on what it means to expand and contract the tonal scale of a negative when needed. (Which is what you're asking about)

IMO, you'll save yourself a lot of "trial and error" pain by imbibing some quality writings on these subjects. Coming to the forum to ask specific questions is fine, but studying what has been written by people like Horenstein and Adams will get you what you need faster, and help you understand the issues better.

[Bruce Watson]

All this is saying is "expose for the shadows and develop for the highlights" which is about as old as photography itself. There are dozens if not hundreds of exposure and development methodologies out there, but they all devolve back to this.

[Serge S]

Excellent explanation!

This is accurate, but not very precise. The Zone System is a lot more precise: you measure the scene contrast and then find a specific development time (which you've tested out in advance) for the contrast conditions in that particular scene.

I think where you are getting confused is with the "overcast" conditions. Subjects under overcast skies, but without the sky in the image are low-contrast subjects; there are no areas lit and shadowed by direct light. On the other hand, on day with bright overcast where you have a scene with the sky in it, the sky can be quite bright. The problem here is that the rest of the scene is low-contrast. Bright overcast landscapes are often a challenge.

Also, as mentioned before, if you shoot roll film, you may want to simply find one good "normal" development time that places negatives of normal-contrast scenes in the middle of the contrast range of the printing paper you are using (say #2-#3 filtration with VC papers) and deal with needed increases or decreases of contrast by changing paper contrast.

If you really feel the need to tweak development times, then learn the Zone System well, how to place shadows, meter highlights and then establish film-developing times for the different scenarios you encounter. Most roll-film users don't bother with this, however. Nor do I recommend it, especially when just starting out.

From your other posts, I assume you are applying the Zone III shadow-placement technique from the Zone System. That will get you well-exposed negatives. The next step is to meter highlights and identify scenes that are "normal" (textured whites "fall" in Zone VIII - five stops away from Zone III). Make negatives of these scenes. Develop and print them with a #2.5 filter. Tweak development time until most of your "normal" scenes print well in the #2 to #3 filtration range. Then leave it at that for a while. You can use the higher and lower contrast filters for scenes that need them.

Best,

Doremus