reversal BW, strange question re archivability

sanmich

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I know it's a long shot, but some here surely have some deep knowledge of processing chemistry:

I am shooting BW 16mm film, just for the fun of it. Family stuff, that is very important to me to keep on the log term.
It's Tri-x reversal.
the process involves negative development, dissolution of the formed image in a sulfuric acid solution, exposure to light to "burn" all remaining sensitive material, re-developement, fix and rinse.

I did the process myself at home a few times. It involves a lot of work, and is quite messy. This process ended with a sequence involving (in rewind tanks):

10 min fix
2 min rinse
2 min Hypo cllear
6-10 min rinse
final rinse with wetting agent

Since then, I have started to send those film to a company, and later discovered that they only fix for 2 min, and rinse for 2min, and that's it.

As said, am concerned by the long term archivability of these films, and I have started to re-do the whole last part on the films I received from them, but I'm starting to wonder if it is necessary:
My thoughts are:
since no sensitive material is supposed to be left in the film, maybe the short fix is enough?
if a short fix is done, maybe there is no need for the Hypo clear/long rinse?

re-doing the process is not such a problem but drying the films is a mess, and sometimes results in damage to the film. If I can be quiet about the archivability, I would gladly skip this step, but I need to be sure...

Your thoughts?:)
 
When I started reading your question, the first thought that came to my mind as I read was "well, doing it himself, at least he knows it will be fixed and washed right, since that's what really matters".

I think you are being right to worry.
 
Mike, thanks for your answer.

In the mean time, I had an idea:
I remembered that I have an old Kodak Hypo test solution.
I don't know if this stuff is stable enough, but I tried it on the film, and it looks pretty clean. very low Hypo residue.
So now, I'm even more tempted to leave it as it is, but still. Not sure...
The thing is: I would like to make a long roll out of the last batch (last couple of years).
Once mounted, no way to split it back to rewash it (I mean, I could do it, but it's even messier, and at any rate, I would be mixing between rolls thus loosing tracks of the ones that come directly from the company).
Any input is still very much appreciated!
 
San Mich the temperature of the rinsing water plays a role, 10 mins @ 20°C is okay. A 2 minute fix is short but the accepted standard in the motion picture world the used temp is 38°C though and not 20°C. The lab seems to follow the recommendations from Kodak. You can always refix the film and rinse it for longer time. The last step might not be a bad idea. Here's a link to the ECN-2 process I know different than B/W but it shows the Kodak recommended workflow . Another thing shooting stock is not designed for best archivability, for that Kodak sells KODAK Panchromatic Separation Film 2238.

Dominik
 
A 2 minute fix is short but the accepted standard in the motion picture world the used temp is 38°C though and not 20°C. The lab seems to follow the recommendations from Kodak.
Dominik

Hi Dominik

Thanks for pointing to the temperature thing.
I wasn't aware of the difference, and it explains quite a lot.
That being said, I didn't find any reference to Kodak recommendations.
If you have the data, it would be great.
Thanks
 
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