Confused with fixing

[andre mueller]

Ok, so I'm done shooting for today and have just tested a snipped of film against the fixer.
That solution had already done 4 120 films in the last couple of weeks.
I poured a small puddle on the table and dropped the snipped in.
It cleared after 30 seconds.
Can that be?
And did I understand you correctly that my film will be finished fixing after 1 minute?

 

[Roger Hicks]

Ok, so I'm done shooting for today and have just tested a snipped of film against the fixer.
That solution had already done 4 120 films in the last couple of weeks.
I poured a small puddle on the table and dropped the snipped in.
It cleared after 30 seconds.
Can that be?
And did I understand you correctly that my film will be finished fixing after 1 minute?

Yes, and yes, though longer will do no harm: I normally go for 2-3x clearing time. Best way to check clearing time: http://www.rogerandfrances.com/subscription/ps how process 35-120.html -- about 3/4 of the way down. From the same site:

Fix for at least twice the clearing time. Fixing for more than this will rarely do any good, though equally, it will do no harm unless fixing is very prolonged: typically, 15x the clearing time or more. In other words, if the spot clears in 20 seconds, the minimum fixing time is 40 seconds; you can give 60 seconds for good measure; and beyond about 300 seconds (5 minutes) there is a slight but increasing risk of the fixer attacking the image as well.

If you re-use the fixer (which makes eminent sense, both economically and environmentally), this approach has the additional advantage of functioning as an exhaustion check. When the clearing time in the used fixer is twice the time for fresh fixer, it's time to mix new. This has a safety margin built in: if you're short of fixer you can go to 3x, but fixing times can get inconveniently long, and 3x clearing time really is as far as you want to go in any case, because fixer with any higher silver concentration may not fix adequately.

Cheers,

R.

 

[andre mueller]

Gracias 🙂