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Raffay
22-Feb-2013, 21:51
Hello

I see a lot of formulas for developers I mean in terms of dilution, I initially thought that it is primarily for saving on developer. However, while I was looking for different films to buy on the internet, some films had instructions like "for better tonal values use 1+4 or 1+10 etc. etc."

I want to know does dilution affects how the film is finally developed, is there any science behind it?

Cheers
Raffay

Heroique
22-Feb-2013, 23:49
Lots of ways to address your question.

And yes, lots of science, but personal experience & plenty of notes prove best for me.

One example: For contrasty negatives (imagine a snowy scene w/ evergreens in broken sun), I’ve often used a dilute developer & increased development times to help preserve shadow detail, while also keeping sufficient density in the high values. I usually plan this development process at the time of the actual shot, giving the shot more exposure than I normally would. A search for “compensation development” will generate a lot of useful information about this specific use of dilute developers.

Leigh
23-Feb-2013, 00:23
One fundamental requirement...
You must always use at least the minimum amount of concentrate for the amount of film being processed, regardless of what dilution you use. Developer capacity is on the spec sheet, given in "rolls". A roll is one 36-exposure 35mm, one 120 roll, four 4x5 sheet films, one 8x10 sheet film, or anything else that can be proofed on a single sheet of 8x10 paper.

=====

Exposure (effective ASA), dilution, agitation, and development time all affect the final results.

The tradeoffs are different for every film/developer combination.

If you really want to nail a combination you need to go through the full process calibration used for the Zone System. That's really overkill for most people, but it's there if you want to use it.

The main factor controlling your results is consistency. You MUST do everything exactly the same every time.

- Leigh

Doremus Scudder
23-Feb-2013, 03:03
Just a couple of comments to augment the above.

First, compensating developers are usually weaker (i.e., more diluted) and work to reduce contrast because they exhaust in the denser areas of the negative effectively stopping or slowing down development in those highlight areas, but keep working in the shadow areas, which are less dense. This effect only works if there is enough time between agitations to allow the developer in the denser areas to get used up, so compensating developers are often used together with schemes of reduced frequency of agitation. Some use stand developing (where agitation is reduced to once every few minutes or longer) for extreme compensation. Many "normal" developers can be used more dilute and with less frequent agitation to achieve this compensating effect.

Some developers, such as D-76, contain a lot of sodium sulfite at full-strength dilution. This relatively high concentration of sulfite acts as a silver solvent during developing. It dissolves some of the developed-out silver and then redeposits it on other silver grains. This has the effect of softening the grain, but reducing acutance of the negative somewhat. Many like the smooth look of solvent developers. Note that the instructions for D-76 say that you should dilute the developer 1+1 if you want less solvent effect (sharper, coarser grain, but more acutance). In this case, the dilution has a direct effect on grain rendition.

With many developers, diluting has no real effect if you keep the agitation intervals short and extend developing time to compensate. This can, however allow longer development times in cases when full-strength developer would result in uncomfortably short times.

Finally, I found that diluting some developers can reduce fog a bit with extended development. I've used HC-110 diluted 1+63 from concentrate to get expansions (N+1 and N+2) from T-Max films. For some reason, using the 1+31 dilution seems to fog the base more and affect shadow detail. I'm not sure why this happens.

Hope this helps a bit,

Doremus

Raffay
23-Feb-2013, 03:50
I am using D23 at full strength with 5 sec agitation per minute. I think my pictures are not very sharp and are quite high in contrast, what dilution do you guys recommend. Here is a sample:

http://www.flickr.com/photos/february71/8484796121/

Cheers
Raffay

Bruce Watson
23-Feb-2013, 09:34
I want to know does dilution affects how the film is finally developed, is there any science behind it?

If you want to know the science behind film development, there are huge tomes on the subject. Grant Haist wrote the definitive work, Modern Photographic Processing (http://www.haistpress.com/books-on-processing.html), in two volumes. Took him something like 20 years. Over 1400 pages total. You want detail, this is where the detail lives.

The quick and dirty condensed version can be had from books like Anchell and Troop's Film Developing Cookbook (http://www.steveanchell.com/index.php?option=com_content&view=article&id=52:the-film-developing-cookbook&catid=38:technical-books&Itemid=113).

The super short version is that you increase dilution of developers primarily for two reasons. First is economy -- use only the developer concentrate that you need and no more. Second is time -- more water means longer development times to reach the same density. This is often useful since too short a development time can create uneven development artifacts.

Years ago I carried out some fairly detailed experiments on my own trying to figure out this very question about dilution. I did this with HC-110 and 5x4 Tri-X, and later with XTOL. What I found about graininess and tonality is that while there is a small effect from changing dilution, it was quite small -- I could just barely see it with a 10x loupe on a light table, comparing films side-by-side. I couldn't see it in a print until 15x which for 5x4 film is a print of impractical size. The difference was that the film grain was a little better formed (a tiny bit bigger, a tiny bit sharper) at higher dilutions, and there was a tiny bit more micro-contrast at higher dilutions. The effects on tonal values were vanishingly small, and certainly not worth the trouble.

In my work I've found much bigger effects on tonality from exposure and development time. What works for me is to have just enough density in the film to render the tonality I want in the final print, and no more. Years of researching brought me back to the most basic of principles in photography: Expose for the shadows and develop for the highlights. This has been the "secret" of B&W chemical photography for the last 150+ years.

So, you want better tonality? Control your negative's density by getting the proper exposure and proper development time. There's no magic bullet -- no magic dilution. Just a lot of work learning your process.

premortho
24-Feb-2013, 15:56
I'm going to have to agree with Bruce on this one. D-23 is a "soft" developer...maybe the best soft developer ever. You have to adjust your exposure times until you hit the magic that this developer is famous for. For Pan film, use same numbers as D-76 (time) for Ortho, use D-76 numbers for a guide, then inspection. I don't know what film you are using, but the developer is not the problem. Greta Garbo can't be wrong.

Raffay
24-Feb-2013, 18:50
I'm going to have to agree with Bruce on this one. D-23 is a "soft" developer...maybe the best soft developer ever. You have to adjust your exposure times until you hit the magic that this developer is famous for. For Pan film, use same numbers as D-76 (time) for Ortho, use D-76 numbers for a guide, then inspection. I don't know what film you are using, but the developer is not the problem. Greta Garbo can't be wrong.

I am using Ilford HP5, FP4, and Kodax TMAX400

premortho
25-Feb-2013, 15:48
I'm probably not the best to consult on this problem. I've only shot three brands of film for other than snapshots, for 65 years. Ansco (the best), Kodak, and Arista rdu. I tried a roll of hp-5 once, didn't like it, so never kept at it to get it to work. Never have used T-max films either. I only use Arista edu. ultra 100 because I can't get plus-X anymore. I have heard from friends who use Ilford that they expose hp-5 at 250, and fp-4 at 80 or 64. Kinda the opposite of D-23 is Rodinal. If you can get Rodinal developer, try that and see if you like it better.

mdm
25-Feb-2013, 18:01
If your scans look soft, its probably not the developer. Assuming the exposure was in focus to begin with, then the scanning process will expend some of the negatives inherent sharpness. On an epson flatbed scanner a film holder that can be focused and that keeps the negative flat, such as a betterscanning holder or a home made version, helps a lot. Then if you want more sharpness wet mounting may be the way to go. Scanned film usually needs some sharpening in photoshop or some other image editing program.

David

Raffay
26-Feb-2013, 08:28
I was reading up D23 in the film development cookbook, and it was referred to as a divided developer. The first bath was D23 and the second bath was Borax granular, I have been using D23 only and want to know the second bath is required.

Raffay

Corran
26-Feb-2013, 08:48
Out of curiosity I looked up the T-Max Developer tech pub. It mentions that 45ml of developer should be added for each roll of 36-exposure 135, so I assume that's how much developer they say is being used.

However, I've been experimenting with different dilutions and I used 6ml in 240ml of solution for a roll of 135, which worked fine. I wonder if there is a better way to determine the absolute exhaustion rate of a developer?

chassis
26-Feb-2013, 10:18
My current combination is Tri-X exposed at EI 100 and stand developed in D-76 1+3. My normal te is about 11.5-12 minutes at 68 deg F. I haven't read much about this combo. I like the results.

Raffay
26-Feb-2013, 12:06
Divided D-23 is a different formula and approach.

One recommendation is to shoot at 1/2 box speed (HP5+ and TMY at 200, FP4+ at 50). Another recommendation is to develop in D-23 1:1 rather than full-strength.

As already stated, expose for the shadows (and develop for the highlights). This is much easier if your lighting is ideal to begin with. Learn how to find lighting that is already perfect for black and white film, and you'll save a lot of time. It sounds like a joke, but it's meant in earnest. The light should be not too harsh, and not too soft. Then you can concentrate on the subject, and with Large Format equipment they will automatically look beautiful.

Thank you Ken, I guess it is time for me to read up and bring my knowledge up a little before I make someone go mad explaining things to me. I actually don't exactly know how to go about expose the the shadows and develop for the highlights... So I guess it is time for me to quit asking and start reading so that I can ask more questions that require clarifications and not concept building ones :)

Btw, your photography and specially the D23 formula on your site made LF possible in Pakistan as there are no other chemicals available for some strange reasons.

Cheers
Raffay

mdm
26-Feb-2013, 13:32
Even more important than the reading is to do, and then to learn from your own mistakes. Sometimes reading is the last thing you should do. The zone system is best left alone until you need it, if at all. It is a potential minefield of fussiness and infinite testing. Experience is the best teacher. Maybe take lots of notes and keep it simple until you find a system that works for you. And go back to the theory later when you can use it to explain some of your results.

premortho
26-Feb-2013, 14:25
I'm going to make the most outrageus, old fashioned recce on here. If you are shooting 4X5, get a box of Ilfords Ortho+. Develope it under a deep red safelight. In un-divided D-23. You will learn more about film developing in one box of Ortho film than in almost any other way. Especially where you live. After you go through that box, and realize that panchromatic film is the same stuff, except has an added dye to make it sensitive to red light. So, you can learn exactly how film responds to exposure vs. developement. And it all translates to panchromatic film, but without having to litterally work in a stygean gloom. Like I once said, I started 67 years ago. So I learned to develope undewr the red light. My grandfather was a great believer in the Watkins Factorial Metheod of developement, and he taught it to me. I reccommend you apply it to your work. Essentually, you time from the instant the plate or film is drowned in the developer until it flashes up. You multiply that amount of time by a "factor", depending on the developer.

premortho
26-Feb-2013, 14:31
Once you develope a system of factors, you'll have a grip on developement, even on that pesky, over-rated, but almost universally used pan film. On that subject, my grandfather had a great respect for pan film. "Good for portraits of ladies over 25 years old".

Raffay
1-Mar-2013, 18:11
Hello,

I am thinking of a 1:5 ratio for D23. I have a 1.5 Litre tank so I was thinking 250ml of stock and then5 parts water to make 1500ml. This will save me on developer and I may get some good results, just want to try. I am not sure by what factor i am to increase the development time by. Like I am developing Ilford fp4 for 7 mins and Kodax tmax 400 for 10 minutes, I don't think it will be 35 and 50 respectively i.e. original time times the 5 the dilution ratio, would appreciate your input, thank you.

Cheers
Raffay

Bruce Watson
2-Mar-2013, 06:40
I am not sure by what factor i am to increase the development time by. Like I am developing Ilford fp4 for 7 mins and Kodax tmax 400 for 10 minutes, I don't think it will be 35 and 50 respectively i.e. original time times the 5 the dilution ratio, would appreciate your input, thank you.

In general, development time for continuous agitation varies as the square root of dilution. For example, if your normal development time is 7 minutes in a 1:2 solution, and you triple dilution to 1:6, your new time would be 7(sqrt(3)) = 12.1 minutes.

As agitation "slows" the relationship between time and dilution becomes both longer and weaker. So for intermittent agitation (like 35mm inversion agitation in a small tank), many people like to start with the idea that doubling dilution -> doubling development time. So if your normal time is 7 minutes and you double dilution, you then double development time to 14 minutes.

When you get to stand or semi-stand agitation, all bets are off. You'll just have to test and see what works best for you.

And I should reiterate that these are considered starting points. You'll still have to test and optimize times for your materials and individual workflow. And you should check to make sure you use enough stock developer to avoid exhaustion of the developer; developer exhaustion can play havoc with the image and can make a mockery of your development times.

premortho
2-Mar-2013, 19:31
Well, Raffay. What to say. If you dilute D-23, it's a one shot developer, so develope than throw it away. If you use D-23 straight, put it back in the dark brown bottle with a screw top, and top it up with a little fresh developer (kept in real small bottles) seems like that's a little more economical, doesn't it? And economical doesn't always mean money...it's also with chemicals, which you may not be able to get any time you want them. Likewise, every dilution of D-23 changes the way the developer acts.
Hello,

I am thinking of a 1:5 ratio for D23. I have a 1.5 Litre tank so I was thinking 250ml of stock and then5 parts water to make 1500ml. This will save me on developer and I may get some good results, just want to try. I am not sure by what factor i am to increase the development time by. Like I am developing Ilford fp4 for 7 mins and Kodax tmax 400 for 10 minutes, I don't think it will be 35 and 50 respectively i.e. original time times the 5 the dilution ratio, would appreciate your input, thank you.

Cheers
Raffay

Raffay
2-Mar-2013, 20:30
My point exactly, if I do 1:1 Dilution then to make 1.5 litres I will have to take 750ml stock and add 750ml water, that will leave 250ml in stock which will be useless as it will not be enough for the next round and I am not sure if it is good idea to make 750 stock next time rather than the usual 1000ml. I was hoping that if I could 1:5 then the math works fine, and wanted to know if that much dilution will improve development and if yes by how much I should increase the development time.

Cheers
Raffay


Well, Raffay. What to say. If you dilute D-23, it's a one shot developer, so develope than throw it away. If you use D-23 straight, put it back in the dark brown bottle with a screw top, and top it up with a little fresh developer (kept in real small bottles) seems like that's a little more economical, doesn't it? And economical doesn't always mean money...it's also with chemicals, which you may not be able to get any time you want them. Likewise, every dilution of D-23 changes the way the developer acts.

premortho
3-Mar-2013, 05:49
Well, my point is, if you use D-23 straight (not diluted), you put it back in the bottle (quart) for next time. You only would make up the little bit that was absobed in the emulsion. Even if you don't make up what you used, it keeps for 3 months or more anyway. From what I understand about where you live, I'd lay in several pounds of the chemicals just in case the supply gets cut off.

chassis
3-Mar-2013, 08:09
I need to correct my previous post for the archives. I am using D-76 1+2, and stand developing Tri-X at EI100 for 11 minutes at 68F for "normal" or "N" results.

Processed a negative yesterday using this approach, and it came out looking well-exposed with reasonable contrast. I will contact print it tonight or tomorrow and see how it looks.