Fixer failure.

[gbroadbridge]

The Ilford datasheets (available at www.ilford.com) contain a wealth of information.

There you will find details about reuse and replenishment. To quote from the copy in my darkroom (which may or may not be the same as online) the following are important

Fixer pH
Specific Gravity of the Fixer solution
Film Clearing time
Silver Concentration (should be < 8mg/l or 2 mg/l for archival prints)

Really, Fixer is cheap enough to just throw away after 40 10x8 prints.

500ml of fixer costs me around 50 cents <shrug>

Graham.

 

[Mike Kennedy]

Just wanted to thank all the members who posted a reply. Thank goodness the film was not that important, meaning, it was not shots of Bigfoot or my decent off Mlt.Everest. Chalk it up to a small expense for a huge lesson. Hell,if life hands you a lemon make lemonade!
I will now use a "clip test" or a few drops of newly purchased Edwal Hypo Check.

Mike

 

[dancqu]

...what about dissolved silver and other contaminants?

Helen B has supplied information on the silver content
of papers and film. Nearly all papers run close to 1.6
grams per square meter or .08 gram per 8 x 10.

For archival results Haist has said the limit per liter is .2
grams and Ilford sets .5 grams per liter as the limit.

Worst case, very little exposed sheets; at best Haist's
limit will allow for 3, 8 x 10s per liter and Ilford's limit will
allow for 7, 8 x 10s.

Ilford's capacity limits for Rapid Fixer, film or paper
strength, are the same; 40, 8 x 10 FB sheets per
liter working strength. That 40 is not an
archival limit. Dan

 

[dancqu]

Helen B has supplied information on the silver content
of papers and film. Nearly all papers run close to 1.6
grams per square meter or .08 gram per 8 x 10.

For archival results Haist has said the limit per liter is .2
grams and Ilford sets .5 grams per liter as the limit.

Worst case, very little exposed sheets; at best Haist's
limit will allow for 3, 8 x 10s per liter and Ilford's limit will
allow for 7, 8 x 10s.

Ilford's capacity limits for Rapid Fixer, film or paper
strength, are the same; 40, 8 x 10 FB sheets per
liter working strength. That 40 is not an
archival limit. Dan

I'm amending that last paragraph. Ilford's PDF on the
subject is misleading leaving one to think that, film or
paper strength, 40, 8 x 10s per liter working strength
is correct. In short I've decided that half that 40
is correct for the 1:9 paper strength dilution.

So, 1:4 or 1:9, 200 8 x 10 FB prints is Ilford's capacity
limit for 1 liter of their Rapid Fixer. Also it is the limit
for their other fixers and for Kodaks Rapid fixers.

The above applies to that last paragraph of my
previous post and does not apply to
archival processing. Dan

 

[wfe]

Had my very first experience with fixer failure today. After hundreds of rolls of film this was my first problem. HP5+ came out green and opaque. I was in a total panic expecting beautiful negs. I caught my breath and thought about it for a few minutes and decided that it had to be the fixer so I opened a new container of fixer and remixed. Ran the film back through the new fixer and the negs look great. Not sure if they are as good as they would have been but they ore more than printable.

 

[dancqu]

[QUOTES=gbroadbridge]

"That will track pH but what about dissolved silver ...?"

A most important consideration. That is dissolved
silver per unit volume. The amount of chemistry needed
to fix an 8 x 10 is about 6 ml of A. Thio. or 6 grams of
S. Thio. anhydrous.

By Ilford, dissolved fixer per liter maximum for archival
results is 0.5 grams per liter and by Haist 0.2 grams per
liter. Worst case, unexposed paper, that max is 6, 8 x 10s
Ilford or 2, 8 x 10s Haist. The amount of chemistry needed
per liter is 36 ml or 36 grams Ilford, and 12 ml or 12 grams
Haist, per liter.

Those amounts of chemistry in one liter make for
extremely dilute fixers. Using fixer so dilute will produce
archival results with one fix and, as a little arithmetic will
show, makes for great milage. In fact one may expect
as many prints can be put through as one
would using the two bath method.

I shoot for silver levels somewhere twixt Ilford's
and Haist's maximums; 4, 8 x 10s per liter. So, on a
liter basis, 24 ml of A. Thio. or 24 grams of S. Thio.
anhydrous make a liter of fixer. Dan

"Every fixer manufacturer states in their data sheets
acceptable levels for silver, are you testing those levels."

 

[Marco S.]

I will now use a "clip test" or a few drops of newly purchased Edwal Hypo Check.

Mike,

You can also check after fixing, to be sure, that the bath completely fixed the film.

Marco