Fixer capacity and TMax

[PVia]

Of course, we've all read and experienced the fact that T-grain films use fixer capacity more robustly than other films, but does anyone know exactly how much more? I usually count the number of films that go through my fixer, but when processing TMax films, should I count every film as if it were 2 films, or what?

Thanks in advance for your input!

 

[Paul Verizzo]

Of course, we've all read and experienced the fact that T-grain films use fixer capacity more robustly than other films, but does anyone know exactly how much more? I usually count the number of films that go through my fixer, but when processing TMax films, should I count every film as if it were 2 films, or what?

Thanks in advance for your input!

Cut a bit of film leader, fresh, not the first, old bit. Put it in your fresh fixer, both in a bowl or cup. Swirl a bit. Note how many seconds to clear. Now, how long you want to extend that is up to you, but maybe 2X. Or, just keep testing until your used fixer is so slow that you get tired of waiting for a snip test result.

 

[PVia]

I know about snip tests, but I was just wondering if anyone had a capacity count for TMax...

Thanks, though...

 

[Trevor Crone]

I slavishly put 40 sheets of 4x5 TMax 100 through 1 litre of working strength fixer diluted 1:4 (Fotospeed FX30 odourless fixer). I wash the film thoroughly for 30-40 minutes changing the water every 5 minutes with vigorous agitation, this removes any trace of the 'pink' colour.

 

[Lowell Huff]

I know that it is the conventional thinking that "designer grain" emulsions require more fixer solution to fix than do "random grain" emulsions. I have never seen any empirical data to support this supposition. The fact is that "designer grain" emulsions are about using less silver per square meter than more. Since we are fixing silver, less silver implies more capacity per liter of solution.
While removing the sensitizing dye stain is not a function of fixing, it is completed in the fix bath. Fixing capacity is a function of the amount of Amm thio or Sodium thio in the working solution. Dye removal is a function of the amount of SODIUM SULFITE in solution. Two different reactions.
Here is another statement bordering on heresey. " Washing vigorously for more than ten minutes is a waste of life!"

 

[Paul Verizzo]

I'd prefer a snip test...

I know about snip tests, but I was just wondering if anyone had a capacity count for TMax...

Thanks, though...

....over "reccomended" number of rolls. Probably a very conservative CYA number. Too many variables between the labs at, say, Kodak and your home. And you don't have to add!

 

[Photo Engineer]

Have you tried the Kodak data sheet? They have lots of information there on process capacity.

PE

 

[kodachrome64]

I'm going to have to agree with Paul, a snip test is probably the best way. There are just too many variables to say you can fix X number of rolls of traditional films and X number of rolls of T-grained films in a liter of fixer (I would think). The snip test will tell you what you need to know and is giving you data on YOUR methods and not the methods of the lab. I would also agree that EK's estimate is probably pretty conservative. Let's remember they are in this business to make money. You can re-use your fixer pretty much as long as you are willing to wait...it comes down to however much your time is worth.

Prepare a pint of fix for traditional films and a pint for t-grained, and compare how much time it takes for each to exhaust it. Use whatever threshold you like, though most seem to consider fixer exhausted when it takes twice the time to clear as with fresh fixer.

 

[dancqu]

I slavishly put 40 sheets of 4x5 TMax 100 through
1 litre of working strength fixer diluted 1:4,
(Fotospeed FX30 odourless fixer).

I wash the film thoroughly for 30-40 minutes changing
the water every 5 minutes with vigorous agitation,
this removes any trace of the 'pink' colour.

An equivalent of 10 8x10s or that many rolls of 120
using 1/5 liter of fixer concentrate; 50 rolls per/liter
of concentrate or 20ml of concentrate per roll.
Likely the concentrate is about the usual
strength as concentrates go.

That 20ml is what I was using on other than iodized
films some time back. A very dilute fixer, 1:24. Slow
but down the drain when done.

The fix was followed by three ROOM temperature
washes and a PhotoFlo; roughly the Ilford
sequence for film. Dan