Questions about developers

snark · Jul 17, 2025

Being a rank amateur hobbyist, I don't shoot enough film to warrant mixing gallons of developer at a time and letting much of it expire, so I broke down a gallon of ID-11 powder into four parts, sealed them in vacuum bags and stored them in a cool, dark environment. Over time, the powders started turning darker, and my latest batch of this stuff yielded consistently thin negatives. Maybe I should start using Diafine and mixing the whole gallon, as it has a very long shelf life. Any other suggestions?

The Diafine instructions recommend exposure index of 250 for the film I'm using (FP4+). What does that mean?

gk fotografie · Jul 17, 2025

snark said:
Being a rank amateur hobbyist, I don't shoot enough film to warrant mixing gallons of developer at a time and letting much of it expire, so I broke down a gallon of ID-11 powder into four parts, sealed them in vacuum bags and stored them in a cool, dark environment. Over time, the powders started turning darker, and my latest batch of this stuff yielded consistently thin negatives. Maybe I should start using Diafine and mixing the whole gallon, as it has a very long shelf life. Any other suggestions?

The Diafine instructions recommend exposure index of 250 for the film I'm using (FP4+). What does that mean?

I don't know how much experience you have with developing film, but I wouldn't necessarily recommend Diafine to less experienced people. It's a two-bath developer, so you're not just making one gallon when you mix it, but two separate one-gallon developers (Bath A and Bath B) that you have to use one after the other in the same development run. Also, keep in mind that Diafine is incredibly expensive and usually quite hard to come by, at least in Europe and perhaps also in the US.
While this developer is excellent once you get the hang of it, I would personally opt for something else (and a smaller package!). Also, realize that cross-contamination, if even a little bit of Part B ends up in Part A, is disastrous — you can simply throw away the entire Bath A — and you don't want that with a developer this expensive. Exposure index (EI) actually means the ISO value, ASA (American Standards Association) is actually a fairly old name, as is the old German DIN (Deutche Industrie Norm), but the ultimate meaning is the same for all. (by the way, opening either a liquid, mixing it with water or mixing a powder means that air has been introduced, regardless of whether you seal everything airtight immediately afterwards, so a long shelf life when you mix Diafine A+B with water and store it is rather wishfull thinking)

webestang64 · Jul 17, 2025

If I were you I'd just use D-96 and be done with it as it is very easy to use.

https://www.bhphotovideo.com/c/product/1524954-REG/cinestill_800349_d96_b_w_motion_picture.html

Steve Anchell · Wednesday at 2:09 PM

This is a good question and it is good that you are reaching out for advice. I would like to begin by saying this: every decision you make when it comes to film development is based on how important your photos are to you. There are many ways to cut corners, but invariably they all lead to inferior quality.

First, dividing any powder formula is a big no-no. There is no way to guarantee that the powder will pour out in equal proportions. Don't do it.

Second, don't use Diafine. Popular with many amateurs, the formula makes many claims, including speed increasing for low light, superior tonality ... test the developer against D-11, and you will see that the claims are false. While many photographers swear by it, and I include the formula in The Darkroom Cookbook, there is a reason that photographers such as Ansel Adams, Wynn Bullock, Ralph Gibson, Imogene Cunningham, Mary Ellen Mark, et al, never used it. At least not a second time. :blush:

Third, why mix a gallon of any developer? Purchase a 1 liter bottle of premixed Ilford DD-X, D-76/ID-11, Rodinal, Kodak HC-110, or other formula and dilute it as needed for use. You can increase the shelf-life of any developer if you decant it out of the plastic bottle into an amber or brown 1-liter bottle and store it in a cool, dark place such as under your kitchen or darkroom sink.

Finally, no developer or fixer lasts forever. If you don't use it before it goes bad, c'est la vie. Don't try to "poor boy" it when it comes to the quality of your work.

BTW, the one developer that appears to last forever is Rodinal. I have a bottle that is more than 20 years old, and it is still developing film. (Why do I have a 20-year-old bottle of Rodinal? Because it got misplaced in a storage box on my move from Colorado to Oregon in 2006 and when I found it recently, I developed a roll of film, and the negatives came out as good, some might say better, than those developed in fresh Rodinal. I intend to develop another roll every few years until either the developer goes bad or I do; whichever comes first.)