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RodinalDuchamp
1-Mar-2015, 06:15
I started tray developing and I noticed as the film was washing that I had some severe finger prints on the them.

I don't remember having touched the films surface other than when I shuffled them for a pretty wash and then after I shuffled them in fixer after development. I used a slosher for development so I know I didn't touch the surface during development.

I'm pretty sure the negatives are damaged beyond redemption but I need to know how to avoid this.



130072

Michael Wesik
1-Mar-2015, 06:52
I would try doing a test with only one sheet of film. If the issue is under-fixing of some kind, processing a single sheet should offer some insight.

Doremus Scudder
1-Mar-2015, 06:58
A major cause of fingerprints is contaminated fingers. I once had some damage from fixer stuck in glove finger that had seeped in through a pinhole in the glove. Other than that, I've never had a fingerprint from tray developing... Hundreds and hundreds of sheets with and without nitrile gloves.

Also, maybe your fingerprints are from another step, e.g., loading/unloading holders, etc.

That said, I haven't used every film out there. Some may be more susceptible to fingerprints than others. Which film is this?

And do try a fix/rewash and see if it helps.

Doremus

vinny
1-Mar-2015, 08:00
One word. GLOVES
You should be wearing them anyway.

djdister
1-Mar-2015, 10:21
As Doremus noted, this is most likely from chemical cross-contamination on your fingers during processing. These are not just "fingerprints." Exactly how you cross-contaminated, and during which step, only you can tell...

RodinalDuchamp
1-Mar-2015, 17:03
OK now that I analyze it is possible that I went from fix back to dev to retrieve the next neg without properly cleaning my hands.

Tracy Storer
1-Mar-2015, 19:36
Keep 2 buckets, one with soapy water(alkaline), and one with plain water. If you need to go "backwards", you can neutralize acids from stop/fix in the soapy water and rinse before going back to the developer. Best to avoid this if possible, but if you think you might need to do it, it can help. I may have read about this from Michael A. Smith in regards to developing by inspection, aka DBI.

RodinalDuchamp
1-Mar-2015, 21:18
Thanks guys. I have modified my process so I take all negs out of slosher at once and then into individual fix trays so no cross cont. I probably had fix on my hands while retrieving. Luckily this was a test run but I now have important negs I don't want to ruin.

Luis-F-S
1-Mar-2015, 21:22
One word. GLOVES
You should be wearing them anyway.

+1 or develop in tanks. L

analoguey
1-Mar-2015, 22:15
What's been said above. Also, if you're doing trays -you should have at least 4 trays, right? Dev, stop, fix, hypoclear /post fix? so your chances of going from fix to dev are reduced -at best, you'll contaminate stop a bit.

Another thing you can try is use one hand only to remove film from dev tray the other to remove from fix tray.
Best thing is to wash hands between solutions. And gloves work well too.


Btw you can still
Print these. I bet they'll Print okay.
One question -aren't you handling the film only at the tips?

Robert Oliver
1-Mar-2015, 22:16
Gloves! And water containers to dip your hands into when needed....

And never touch the emulsion part of the negative to be safe, only grab tips and corners

Doremus Scudder
2-Mar-2015, 07:26
OK now that I analyze it is possible that I went from fix back to dev to retrieve the next neg without properly cleaning my hands.

Don't do this!

As noted above, you should have more than just two trays and shouldn't be going directly from developer to fix. A stop bath is cheap and is simply a much better option than a water rinse. However, you should have something between develop and fix!

As for technique to prevent contamination. Your hands should be like the film; they should never move upstream in the process. So, when development is finished, take up all the films (however you do it; I just grab them all and fan them out in my hand like a hand of cards) let them drain and then immerse them in the stop bath. Don't leave a film in the developer and then go back for it. The same applies to stop and fix.

I bet your fingerprints will go away once you refine your technique and stop contaminating.

Best,

Doremus

Ken Lee
2-Mar-2015, 08:26
I keep a small bottle of rubbing alcohol in the darkroom. After mixing all the chemistry, after putting on my IR goggles (which sometimes have some powder on them)... just before removing the film from the holders... I clean my fingertips thoroughly and blow them dry. That has solved the problem for me. I presume it would work just as well for those who wear gloves.We need to remove oil as well as chemicals from our hands/gloves.

Another option is to discriminate between hands: once the film has gone into the stop bath, only use that hand for stop bath and for subsequent agitation in the fixer. As others have pointed out, never return the fixer hand (or glove) to the developer.

RodinalDuchamp
2-Mar-2015, 09:22
Thanks all for taking time to help me. I've made some adjustments to my process, I will be much more careful now that I know how sensitive the film can be. My experience until now has been in tanks only.

jnanian
2-Mar-2015, 16:43
i always try to fingerprint my negatives and sometimes my prints
it ends up being a mark or authenticity ..

RodinalDuchamp
6-Mar-2015, 17:24
Just wanted to update, I now use gloves and use extreme care when handling wet negs. I am also very careful when taking negs from stob bath to fixer and returning to grab another negative, I rinse my hands in water before taking the next one. Since I've started doing this I have been very fortunate not to have these bad marks. Thanks to all whom offered their advice.

Doremus Scudder
7-Mar-2015, 02:57
Just wanted to update, I now use gloves and use extreme care when handling wet negs. I am also very careful when taking negs from stob bath to fixer and returning to grab another negative, I rinse my hands in water before taking the next one. Since I've started doing this I have been very fortunate not to have these bad marks. Thanks to all whom offered their advice.

RD,

Why don't you just lift all the negatives out of a solution at the same time? That's common practice, and you'll never have to go upstream to get a second or third negative again.

FWIW, when developing, I immerse sheets one-at-a-time at five-second intervals. When time is up, I make sure all the negs are in the same order as they went in, then I lift all (up to 8) negatives out of the developer and drain for 15 seconds (this is figured into my developing scheme). Then, I immerse them in the stop bath one-at-a-time, in the same order as they went into the developer and at five-second intervals. Exactly the same developing time for every negative. I use developer one-shot, so don't care about stop dripping from my gloves into the developer try. However, I could easily just hold the negs over the stop tray after the initial rinse so that didn't happen.

When I've shuffled the negs through the stop for a minute, I gather them up, let them drain and then transfer the whole stack to the fix. I shuffle once through the stack and then start timing. I never have to rinse my hands, since they are all moving downstream, and I never have to go upstream to get a negative.

Hope this helps,

Doremus

RodinalDuchamp
7-Mar-2015, 03:43
RD,

Why don't you just lift all the negatives out of a solution at the same time? That's common practice, and you'll never have to go upstream to get a second or third negative again.

FWIW, when developing, I immerse sheets one-at-a-time at five-second intervals. When time is up, I make sure all the negs are in the same order as they went in, then I lift all (up to 8) negatives out of the developer and drain for 15 seconds (this is figured into my developing scheme). Then, I immerse them in the stop bath one-at-a-time, in the same order as they went into the developer and at five-second intervals. Exactly the same developing time for every negative. I use developer one-shot, so don't care about stop dripping from my gloves into the developer try. However, I could easily just hold the negs over the stop tray after the initial rinse so that didn't happen.

When I've shuffled the negs through the stop for a minute, I gather them up, let them drain and then transfer the whole stack to the fix. I shuffle once through the stack and then start timing. I never have to rinse my hands, since they are all moving downstream, and I never have to go upstream to get a negative.

Hope this helps,

Doremus
I haven't figured out exactly how to lift all all the same time. I am using intervals to place and lift each one separately to avoid handling more than one at once in hopes of avoiding scratches