Fixer life

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TimeShot

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Fixer Shelf Life

Does mixed Black & White film fixer have a shelf life?
Approximately how many rolls of 35mm B&W film will a quart/liter fix?

I have purchased a bottle of Kodak HC110 Concentrate. I understand it has a shelf life of years and a ‘one shot’ developer. Approximately how many rolls of 35mm will a quart/liter HC110 dilution B develop?

I haven’t developed B&W film in a long time and want to start again. Just need a good idea what to expect from the chemistry.

Thank You
 
I wait sometimes a couple of months between developing (a backlog of) film, so I am aware of the fixer going bad. What I do is place a clipped end of a roll of film into the cap of the fixer bottle with some fixer in it, when I dump the fixer into the developing tank. I can see from this clip of film what is happening to the film in the developing tank. I time how long it takes for the bit of clipped film to clear in the bottle cap, then double that time for the film in the tank. If the fixer is still strong it takes less time. If the fixer is weak and near exhaustion then it takes longer. Also, some film types take longer to fix than others.
 
this is my work flow, it will disgust some, but it works for me:

i mix about 150ml ilford rapid fixer +450ml of water giving 600ml of solution. this 600ml fits into the recommended 2 reel paterson tank.

for rolls 1 to 10, i fix around 5 mins.
for rolls 10 - 15 around 10mins
for 15 onwards, i fix around 15-20 mins.
around 20 rolls i get paranoid and i dump and make a new batch.

i keep record of all rolls developed, temp, camera, film and fixer.
 
In terms of capacity Kodak says of Rapid fixer: http://www.kodak.com/global/en/professional/support/techPubs/e103cp/e103cp.pdf
about 100 8x10 sheets per gallon or 26 per litre. Count a 135-36 as an 8x10 sheet.

Storage life once mixed depends on storage conditions, because thiosulfate also degrades spontaneously
see here. Use the clearing time as a rough guide and throw the fixer out when the clearing time doubles, or use hypo check.

Marty
 
Freakscene said:
In terms of capacity Kodak says of Rapid fixer: http://www.kodak.com/global/en/professional/support/techPubs/e103cp/e103cp.pdf
about 100 8x10 sheets per gallon or 26 per litre. Count a 135-36 as an 8x10 sheet.

Storage life once mixed depends on storage conditions, because thiosulfate also degrades spontaneously
see here. Use the clearing time as a rough guide and throw the fixer out when the clearing time doubles, or use hypo check.

Marty
Click to expand...

Man, in that case I have really been wasting a lot of fixer. I saw somewhere the advice to NOT reuse fixer, said "That's ridiculous", but have only brought myself to reuse a volume ONE time. If I understand the comment above, and I'm doing the math right, I should be able to re-use a 600 ml volume SIXTEEN times.

Maybe if we all followed my example, Kodak would not be going bankrupt.

Randy
 
patrickjames said:
You can run about twenty rolls of film or sheets of paper through a liter of fixer. That is a general rule and it isn't really dependent on the dilution of the fix (in Rapid Fixer's case). In practice you don't have to be too scientific about it. If you are not sure fix it longer but you will also need to wash it longer too. Film doesn't need a whole lot of washing. Paper is different. You really can't over fix anything unless you go way over the time. I wouldn't fix anything for more than ten minutes for example, but if you leave something in the fix for 1/2 hour it won't be horrible either.

Or you could just use fresh fix and if you are not sure just dump it and mix new fix. I prefer to do it this way. In the darkroom, with paper, I never reuse fix. For film I mix up a gallon at a time (TF-4) and use it until I get a feeling like I have used it enough and then I dump it and mix a new gallon. Not scientific, but there it is.

If you really want to go nuts you can remove the silver from the fix and use it almost ad infinitum. That is a lot of hassle though.
Click to expand...

I have been dispensing fixer from a gallon jug into a plastic 1 L bottle, 500-600 ml at a time, and then using the volume in the bottle. Like I said above, I use the bottle contents only twice (for film), which is clearly WAY too conservative. I have not reused the fixer for paper .

I think I will use each 600 ml volume five times. That way I am still being conservative (don't have to wonder if my fixer is axhausted), but not an idiot about it.

Randy
 
:D Thank You everyone this is very helpful. Like I said it's been a long time (30 yrs) since I dev. b&w film and didn't remember when I changed fixer. I worked for a newspaper and shot Kodak film developed using D76 w/Kodak fixer. Good memories
 
Mixed fixer: A few months
The capacity depends on the type of fixer and films. Regular bi-cubical type films and a rapid fixer 1+4: 8-10 films for 500ml fixer. But you can test the fix by a titration of Potassium Iodide solution (fixer test). For films: 2g-3g Ag+ is the limit on saturation.

HC-110 dil. B 1+31 : 250ml tank 250/32=7,8ml / film. A 1 ltr. HC-110 bottle will fit for 128 films then. (Going out from the USA HC-110 version).

Hopefully this helps a bit.

Robert
 
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