Bright area on prints

[tim_kimbler]

Thanks for the info on water spots to all. I have made a number of contact prints. Many are lighter on the right edge of the print, about 1/2 inch wide top to bottom. I don't see any thing on most of the negatives, all though a couple are darker on the edge. Is this due to some development problem. I use a JOBO tank and a Besler motor drive with constant 180 reversing motion. My tank is much like a 35mm tank. I do 8 negatives at a time with 10 oz of chemical at room temperature for 6.75 minutes in Extoll. I guess the negative is streaked on the edge.

 

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Tim..........

[marv_thompson]

Please tell us which edge, assuming that the code notches are in the

lower right hand corner with the emulsion facing the viewer, is

affected by the abnormality.

 

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When the negatives are loaded into the drum, does the edge that is

affected run at a 90 degree angle to the rotation, or is the edge in

line with the rotation?

[tim_kimbler]

The bright spot is on the edge opposite the notched edge on all the

negatives with the problem. I guess that would be the end of the

negative. That edge is in line with the rotation.

 

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Tim..........

[marv_thompson]

I would look for a light leak first. If the end of the negative is at

the point where the dark slide goes in and out of the holder, it is

the way I load the holders, I suspect a holder that is allowing light

in. I would try to isolate the holder that is the problem.

 

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When you process the negatives, do all of them have the defect on the

same edge or just random negatives in the batch. If is is random

negatives that also would point towards a film holder problem. For it

to be an aggitation problem, I think all of the negatives that lay

along the line of rotation should exhibit the defect.

[andrew_martin2]

I called Jobo Customer Service this morning and went over, in detail, the problem we are having. I spoke to their technical adviser, Mark (in the US 734-205-9421, until 5PM). He indicated that if the photoflow and stabilizer are introduced to the film while it is still on the reel, then you will begin to build up a contamination on the reels that will begin to affect image density at the edge of the film. This could be either gain or loss of image density. He said that their prescribed method of handling the film at this stage of processing (and also stated in the instructions for the machine), is to take it off of the reel and do this final process for photoflow and stabilizer in a separate container that is not the tank.

 

If the photoflow and stabilizer are being introduced to the film while it is on the reel, then the increase of this flaring problem we are seeing in the images would make sense. Each time the film is processed, the contamination gets worse and the image density change would be increasingly affected. So, at the beginning there was none or very little, of this problem of the current production. and it has increased incrementally over the 12 rolls would also make sense, since there were only two days that two rolls of film were processed together. If one reel has been used for ten rolls of processing, (plus our test rolls now) and it was put in the photoflow and stabilizer on the reels, there is a substantial build up of contamination affecting the film.

 

So, the roll with no density change, if it was put on a reel that had not been used, or used very little, then there would be minimal or no contamination of the reel. If a mostly unused reel was used to process Roll 70 from the R8, that is probably why we see no density change at the edge of the image. The lack of flaring would have nothing to do with the fact this film was shot on a Leica.

 

Mark said that the way to clean the reels was with Lysol or detergent and bleach, and scrub it with a toothbrush to get the residue off the reel. This second method will begin to diminish the integrity of the plastic if done too often.

 

He suggested doing a double blind test with a used reel and a clean one. I figured that if we did not know which reel has been used the most, we could shoot two test rolls and put half on each reel. This should confirm conclusively if the reel has been contaminated because two half rolls will be fine and the other two will show this image density change at the edge of the film.