How do I know when a developer is spent ?

AndyCoulson

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Hi, I'm still very new to this ...

From one dev mix I've so far developed four positive paper 5x4 sheets, and four 200 ASA (ok ISO) sheets of 5x4 film and I'm wondering if that's it for this dev ? It's Ilfosol 3 by the way, if that's relevant, and it's a weird shade of blue now I think.

The sachet says it's good for 2 rolls of 35mm, I'm guessing that's 36 images each, 72.

My dodgy maths works out that 72 frames of 24x36mm (ie 35mm) film is 62,208 mm squared area, and
one sheet of 5"x4" film, 140x112mm area, is 15,680 mm sq, so four sheets is 62,720 mm squared ... ie approx the area of two rolls of 35mm film (36 each)

Does that work ? 2 rolls = 4 sheets ?

And given I've also developed 4 papers as well, then it's definitely time to mix some new Dev ?
(My film images are very 'thin' but as it's old film, and I'm still getting used to using a phone app light meter to meter for the Wista, and I've assumed dev times for 5x4 are similar to 35mm ... so many variables I don't really know what caused the thinness.

Thoughts thoroughly appreciated, thanks,
Andy
 
The usual assumption is a roll of 36ex 36mm or 120, is 80 sq inches which is the came as 4 sheets of 5x4. With modern emulsions development times are the same regardless of the format for the same film.

Ian
 
That's helpful, thanks. Does Fixer and Stop have similar life ? A roll or two ?
 
Have a read of the Ilford Rapid Fixer datasheet also Ilfostop, both have greater capacity.

Ian
 
From memory, a 1 litre working solution of Hypam will fix 21x 80 sq inches.....so 21x 120 films or 21x 10x8 sheets of film.

Mike
 
From Ilford's documents:

1706469702162.png

I generally use separate fixers for film and paper so as to avoid cross contamination particularly of any residual anti-halation dye that ends up in the film fix. I don't think this is strictly necessary, I've just always done it that way.
 
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Thank you - I'm enjoying learning these things.
Shameless Self Promotion Follows:

I have aggregated a great many photography-related documents into a single location for ease of location. Among them are many Ilford, Kodak, et al specifications sheets and publications as well as operating and service manuals for many cameras. Feel free to browse at your leisure:

 
A contact sheet of either 35mm or 120mm film is more-or-less 10x8 or say, A4, so equivalent to one 10x8 or four 5x4 negs. All developers I’ve seen can be stretched to do more, but with decreasing reliability. Many have instructions on how to increase development time for more consistent results. Some developers use replenishment, but that seems to be for larger tanks used commercially.
The obvious solution is to use one-shot developer.
There are kits available to test the condition of fixer.
 
Andy, there is a simple way of keeping tabs on your film fixer.
Mix a fresh batch of fixer - 1 part fixer+4 parts water.
Take a spare piece of undeveloped film and swish it round in the fresh fixer, and time how long it takes to completely go clear. Make a note of this time.
When you process your first batch of film, fix it for twice the clearing time.
The fixer is re-usable, but gradually loses its strength. A piece of undeveloped film will take longer to clear. When the clearing time becomes double what it was originally, discard the fixer and mix a fresh batch.
Quite a few people use this method, and it does seem to work.

Alan
 
Shameless Self Promotion Follows:

I have aggregated a great many photography-related documents into a single location for ease of location. Among them are many Ilford, Kodak, et al specifications sheets and publications as well as operating and service manuals for many cameras. Feel free to browse at your leisure:

Remarkable ... the Complete Self Instructing pdfs would take a lifetime to read, learn, practice - fantastic resource, cheers.
 
Andy, there is a simple way of keeping tabs on your film fixer.
Mix a fresh batch of fixer - 1 part fixer+4 parts water.
Take a spare piece of undeveloped film and swish it round in the fresh fixer, and time how long it takes to completely go clear. Make a note of this time.
When you process your first batch of film, fix it for twice the clearing time.
The fixer is re-usable, but gradually loses its strength. A piece of undeveloped film will take longer to clear. When the clearing time becomes double what it was originally, discard the fixer and mix a fresh batch.
Quite a few people use this method, and it does seem to work.

Alan
I'll try that Alan, good tip. Thanks again.
 
A small refinement on the fixer test is to put a drop of fixer onto the emulsion and wait for it to clear. This exact time doesn’t matter. Now immerse the whole piece and watch for the spot to disappear. This is easier to see than judging a whole piece as it’s tricky to judge the point of complete clearance without something to compare.
 
I use the film clearing test for fixer. Is there an equivalent for paper fixer? 80 sheets of 8x10 is a lot, and I generally make a new batch before then so I've been wondering whether there is a simple way to test it.
 
Fixer is fixer, so the same test should work.
Here’s another method, from the publisher of the Massive Dev Chart.
Perhaps for paper, the critical factor is what’s left in the paper after washing.

https://www.digitaltruth.com/data/formula.php? FormulaID=57

 
I use the film clearing test for fixer. Is there an equivalent for paper fixer? 80 sheets of 8x10 is a lot, and I generally make a new batch before then so I've been wondering whether there is a simple way to test it.
Hi Wendy,
A chap called Peter Hogan used to sell a fixer testing fluid. You take about 10ml of used fix and put in a drop of the fluid and if it turns chalky the fixer is spent. He is no longer in business but I suspect there will be a formula in The Darkroom Cookbook to make your own. Possibly also check John Finch (Pictorial Planet on YouTube) as he seems to mix up various concoctions.
 
A small refinement on the fixer test is to put a drop of fixer onto the emulsion and wait for it to clear. This exact time doesn’t matter. Now immerse the whole piece and watch for the spot to disappear. This is easier to see than judging a whole piece as it’s tricky to judge the point of complete clearance without something to compare.

I used to occasionally do fixer testing but found that keep track of the amount of film or paper processed (I use separate fixers for each) was sufficient.

When I make up a batch of fixer (typically 2 liters at a time) I put up a "sticky note" in the darkroom that indicates the date it was mixed. Then I just track the number of "10x8 equivalents" processed.

For example, TF-4 fixer will handle between 15-20 "rolls" of film per liter of developer. (A "roll" us understood to be 80 sq inches of film, so 1x 135x36, 1x 120, 8x 9x6, 4x 5x4, or 1 10x8 all can be though of as a "roll" in this context.)

Each time I process a "roll" I add this to the running total kept on my sticky note. I replace the fixer when one of two conditions is met: I am approaching max rolls recommended (in this case, it would be 60-80) or 6 months has elapsed since the fixer was mixed. Typically, this means I am well below t he max number of recommended "rolls" at the 6 month mark as I am unlikely to shoot 80x 10x8 equivalents in that time.

I store fixer in repurposed 1/2 gallon brown glass brewer's "growlers" with polycone style caps on them and have never seen fixer exhaustion from this scheme. To the contrary, my films are still clearing in less than a minute at the 6 month mark.

I do the exact same thing for paper fixer.

As an aside: I recently made up 1 US gal of Kodak Fixer because I wanted a hardening fixer for processing Efke films. It is muuuuuuch slower to clear film - taking 2+ min or so - as compared to the TF-4. I'm sure it works fine, it's just a rather different formulation.
 
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