When using a rewind tank, do the times for each stage stay the same? I know it's supposed to take one minute to wind the film from one side to the other, but if the directions call for 10 minutes, does that mean ten passes, or do I need to compensate for only a small portion of film coming into contact with the chemicals at a time?
(I'm using the Photographers' Formulary reversal kit, it's the first time I've tried it and only the second time I've used anything but a spiral tank.)
Times for a rewind tank vs. spiral
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audadvnc
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Check the George Selinsky home processing page, specifically the articles by Martin Baumgarten:
http://www.geocities.com/gselinsky/
I have found the processing times using a rewind tank to be much longer than those of a spiral or any other developing technique due to the relatively short percentage of time the film is surrounded by the chemical bath versus wrapped up on a reel. For instance, I typically develop negative b&w film in D76 for 6 minutes when using the "bucket" method, but will develop a 100' spool of 16mm for a half hour in a rewind processor to achieve an equivalent density. And fixing in a rewind tank takes so long that I do not recommend using traditional sodium thiosulfate fixer - it just takes too long (an hour or more) - use ammonium thiosulfate rapid fixer in rewind tanks.
http://www.geocities.com/gselinsky/
I have found the processing times using a rewind tank to be much longer than those of a spiral or any other developing technique due to the relatively short percentage of time the film is surrounded by the chemical bath versus wrapped up on a reel. For instance, I typically develop negative b&w film in D76 for 6 minutes when using the "bucket" method, but will develop a 100' spool of 16mm for a half hour in a rewind processor to achieve an equivalent density. And fixing in a rewind tank takes so long that I do not recommend using traditional sodium thiosulfate fixer - it just takes too long (an hour or more) - use ammonium thiosulfate rapid fixer in rewind tanks.
I doubled the times, which seemed to work, but there was a problem of some kind.
It didn't fully reverse. After the bleach, it says the rest of the process can be done in the light. At that point, it was a nice negative. After the rest of the steps, it was neither a negative nor a positive. For example, in one section, the background is black. In the negative, this comes out white. In the final, it's gray. In the same section, there's white in the foreground. In the negative, this is black. In the final, it's still black. Throughout there's odd things like this--parts that reversed and parts that didn't. One bit was particularly strange: in the scene there's a black dog. In the finished film, the dog starts out as a negative--white. However, as the scene goes on, she starts to get positive--fading to a dark gray.
What might be the cause for that? Was the second development too short? Too little re-exposure? Something else?
It didn't fully reverse. After the bleach, it says the rest of the process can be done in the light. At that point, it was a nice negative. After the rest of the steps, it was neither a negative nor a positive. For example, in one section, the background is black. In the negative, this comes out white. In the final, it's gray. In the same section, there's white in the foreground. In the negative, this is black. In the final, it's still black. Throughout there's odd things like this--parts that reversed and parts that didn't. One bit was particularly strange: in the scene there's a black dog. In the finished film, the dog starts out as a negative--white. However, as the scene goes on, she starts to get positive--fading to a dark gray.
What might be the cause for that? Was the second development too short? Too little re-exposure? Something else?
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audadvnc
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Solarization can be caused by several process steps. Perhaps you didn't expose the film to a bright enough light after bleaching. Perhaps the bleach was exhausted or you didn't let it work long enough. Or the temperature may have been off on one of the chemicals.
Monobath are you out there?
Last summer I got back a 16mm TriX 7278 roll from Film & Video Services in Minneapolis with bizarre solarized sections and emulsion loss along the edges of the film. They blamed it on expired film, but I think they ran their developer too hot and boiled my image away. But I've not had any problems with their processing several rolls 16mm and S8 since.
Monobath are you out there?
Last summer I got back a 16mm TriX 7278 roll from Film & Video Services in Minneapolis with bizarre solarized sections and emulsion loss along the edges of the film. They blamed it on expired film, but I think they ran their developer too hot and boiled my image away. But I've not had any problems with their processing several rolls 16mm and S8 since.
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monobath
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Sounds like partial solarization, as audadvnc said. But that could be completely wrong, too. It might be the result of incomplete bleaching.
Solarization often, but not always, produces edge effects at light/dark transitions that show up as heavy lines, almost like an outline. They are called Mackie lines. Do you have any of these in your film? They would be white on a non-reversed portion, and black on a reversed portion.
If it is solarization, I'm pretty sure it would have to occur before the bleach phase. In other words, during first development. You might want to carefully check your tank for light leaks. Look around the crank handles and the edges of the lid. Check the drain stopper and the re-exposure window. Take the reels out, cut some strips of unexposed film from a 35mm roll in the dark and put them in the tank. Then put the lid back on and turn on the lights. Work the crank handles like you were processing film. Then lights out, remove the film strips from the tank and put them in a regular developing reel and process them in D-76 or whatever negative developer you have on hand. You should be able to see if you have any light leaks after the processed film is dried.
Solarization often, but not always, produces edge effects at light/dark transitions that show up as heavy lines, almost like an outline. They are called Mackie lines. Do you have any of these in your film? They would be white on a non-reversed portion, and black on a reversed portion.
If it is solarization, I'm pretty sure it would have to occur before the bleach phase. In other words, during first development. You might want to carefully check your tank for light leaks. Look around the crank handles and the edges of the lid. Check the drain stopper and the re-exposure window. Take the reels out, cut some strips of unexposed film from a 35mm roll in the dark and put them in the tank. Then put the lid back on and turn on the lights. Work the crank handles like you were processing film. Then lights out, remove the film strips from the tank and put them in a regular developing reel and process them in D-76 or whatever negative developer you have on hand. You should be able to see if you have any light leaks after the processed film is dried.
I have experimented quite a lot with rewind vs. spiral & bucket methods.
Spiral and bucket timings are the same. (as are most methods when the chemicals are in constant contact with the film)
When using a rewind tank like the G3 you will need to times by 3.5
So 6mins for spiral is 21mins in the rewind.
It is also a good idea to pre heat the tank.
After loading your film add water that is approx 2 degrees warmer then the temp needed for the chemicals, then give it 2 winds. (with the light tight lid on
)
If you are doing long developments try putting the tank in a bath of warm water of the same temp needed for you chemicals.
Also on the bleach step try this until the bleach is completely used up 10mins or more.
And very important with the rewind it to wash properly, I give it at least 5 winds between of water between each chemical step. Add water (of the correct temp) wind once, empty, add more water... So change after each wind so five lots of water is needed the wash off the chemicals between steps.
Good luck,
Chris.
Spiral and bucket timings are the same. (as are most methods when the chemicals are in constant contact with the film)
When using a rewind tank like the G3 you will need to times by 3.5
So 6mins for spiral is 21mins in the rewind.
It is also a good idea to pre heat the tank.
After loading your film add water that is approx 2 degrees warmer then the temp needed for the chemicals, then give it 2 winds. (with the light tight lid on
)If you are doing long developments try putting the tank in a bath of warm water of the same temp needed for you chemicals.
Also on the bleach step try this until the bleach is completely used up 10mins or more.
And very important with the rewind it to wash properly, I give it at least 5 winds between of water between each chemical step. Add water (of the correct temp) wind once, empty, add more water... So change after each wind so five lots of water is needed the wash off the chemicals between steps.
Good luck,
Chris.
I guess the most efficient way to dry film is wound around a drum(dowel).gianni1 wrote:How do you dry the film?
Gianni
I can't be bothered to build one. My method is to hang one end from a solid object using a bulldog clip run the film down my hallway, slide a paperclip through one perforation and attach the paperclip to a tripod via another bulldog clip and back down the hallway, etc. etc. It makes navigating through ones apartment very tedious. I highly recommend it.
Ralphie.