Quick Question Tray Processing

[Leigh]

Interestingly, when I turn on the lights after development, the RO water tray is an inky purple-blue.

Nothing unusual about that. It's the water-soluble anti-halation dye from the back of the film.

If you use a pre-wash, the dye ends up in it.
If not, it ends up in the developer.

- Leigh

[Doremus Scudder]

One caveat!

Yes, you can turn on the lights as soon as the development has been stopped by an acid stop bath IF:

1. Your developer is an alkaline one (i.e., not Amidol, etc.) and is truly stopped by the stop bath and...
2. If your fixer is also acid.

This latter is important. If you use an alkaline fixer, carried-over developer will be reactivated in the alkaline environment and start to work again, this time on the newly-exposed parts of your negatives that just got exposed by your turning on the lights. Developer is not washed out in the stop bath, just rendered inactive. In an alkaline environment it gets reactivated and will start developing again. If you have non-image exposure, fogging will occur (don't ask me how I know this).

Alkaline developer plus acid stop and acid fix and you'll be fine turning on a light right after the stop.

FWIW, it's sometimes fun to turn on the light after the film has been in the stop 30 seconds or so and examine the image with the uncleared image, then transfer to the fix and watch the image clear.

A side note on tray processing: It's not hard; it has been my main method for well over 30 years now. Get a couple of scrap sheets and practice shuffling, first in the light, and then with your eyes closed and then in the dark. You'll find you gain dexterity quickly. Do this before you develop real film.

Best,

Doremus

[Pere Casals]

Can I get away with b&w film using low power red light AFTER develop & stop bath? This would make things a helluva a lot easier for me.

After stop bath you can open lights at full power, no problem. I do it always. Just ensure stop bath time is enough, I open lights after 20 seconds with acid stop bath or 40s with plain water stop bath.

B&W film must be done in the dark, not safe light. Does the entire process have to be done in the dark?

I do that:

> I place the tray inside a paper safe so I can develop lights open, you may use any kind of light tight box. Or you may do that in darkness...

> Then I close lights to move the sheet to a plain water stop bath, after some 40s I open lights, development is stopped so light is not harmful anymore, then I move the sheet to the fixer tray.

> As I'm fixing lights open then I know the fixer strength from the time it takes to clear the negative, this is removing the not developed silver halide that's yellowish. Fixing time should be 2x the time it takes to clear.

> When a sheet is in the fixer tray I can start developing the next one inside the paper safe or light tight box.

[Two23]

For developer i use hc110. Fixer is photographers formulay 4.


Kent in SD

[Bill Burk]

TF-4 is an alkaline fixer, so the advice may be to leave the lights off for a while.

I don't know first hand, but think you might be better keeping the lights out.

[Pere Casals]

TF-4 is an alkaline fixer, so the advice may be to leave the lights off for a while.

I don't know first hand, but think you might be better keeping the lights out.

Bill, I've tested it well and I found that fixing lights open is safe. Checking it is as easy as processing two not exposed film ends, one fixed lights open and the other one in the dark, you won't find a difference in the fog, testing with a densitometer.

Even in the case we open lights just when we move film from developer to stop there is a very little risk that we add fog, because the newly exposed crystals won't start their development until some 1min has passed, because development starts after an induction time, and by then the stop bath has stopped well any development.

This negative was tray processed and "lights open" fixed (common alkaline rapid fixer) , base+fog is 0.10D: https://www.flickr.com/photos/125592...5/28693688313/

Anyway I reiterate, if one finds that fixing film lights open is convenient then he can check that there is no damage, just processing 2 film ends and comparing.

Paper is different... fixing lights open is very risky because it should be ensured that no developer remains inside, wich is specially difficult with FB paper.

[interneg]

There's no reason to use anything other than an acid stop - otherwise you're risking all sorts of problems - especially with a water rinse instead of a stop. In particular you are relying on the inductance time of the processed film being long enough relative to the ambient light in the room you are working in to not cause fog. It's lazy & bad practice. Doremus' procedure is how it's supposed to be done if you want to get the lights on early.

With Ilford & some other FB papers (current Adox etc, however, not Foma & especially not Fomabrom) you can get the lights on 15-20s into the fix, if you are using film strength fix. This is possible because of the structure of the emulsion (very specific controlled grain structures, high chloride, low iodide) & the speed with which it fixes - given that they are designed to fix & clear in 30s, this should not be surprising. The higher iodide (slower fixing) Fomabrom paper doesn't work this way.

[Pere Casals]

There's no reason to use anything other than an acid stop - otherwise you're risking all sorts of problems - especially with a water rinse instead of a stop. In particular you are relying on the inductance time of the processed film being long enough relative to the ambient light in the room you are working in to not cause fog.

With film, 20s in acid stop or 40s in plain water stop are well safe to open lights, development has been totally stopped so induction time plays no role.

Induction time only plays a role if you open lights before development is stopped. I was recommending stopping before openning lights, and considering induction time as an additional safety belt that ensures that no harm is there.

I agree that photopapers are more difficult, and better if fixing well before openning lights. While I've never had a problem with film I've destroyed prints by openning lights.

[Two23]

I gave it a shot last night. Set up my trays in my bath tub and had everything ready. Had my Gralab 300 timer sitting in easy reach on my toilet and film holder in my hand. I turned off the lights, plopped a sheet of 4x5 FP4+ into the HC110, and reached over to start the time. Oops, not plugged in! Used the tiny light on my watch to find the wall outlet and plugged the timer in. Oops--forgot to unplug the red safe light from it. The room lit up red! Quickly unplugged it and decided to continue processing to see what I got. Finished the develop time and dropped the sheet into the 1:3 vinegar stop bath. Gave it a minute, used the dim light of my cell phone to see if anything on the neg. There was! Poured the PF4 into the fixer tray, turned off the phone light, and dropped the sheet into the fixer. Continued until I had washed the sheet for a minute and then turned on the light. There was an image, but there was also a shadow of the edge of the tray across the negative. Obviously the red light screwed it up. Undaunted, I tried a second sheet, this time in the dark. (Had to move the glow in the dark timer further away from the trays.) Success! The neg came out perfectly! Unfortunately the lens was not well focused. At least I now know I can do it. I'm waiting on receiving the Stearman SP810 I ordered to do 5x7 (and 8x10 some day) but until then I can process 5x7 sheets if I need to .

Thanks to all for help.


Kent in SD

[Leigh]

Success! The neg came out perfectly! Unfortunately the lens was not well focused. At least I now know I can do it.

Very good, Kent.

Congratulations.

- Leigh