bleaching negatives to remove flare/light leaks?

I've read about this very briefly in a magazine where Bruce Barnbaum used some kind of bleach on a negatives to tone down a light leak.

Recently I've been using a seagull medium format camera since it was the easiest to get my hands on and I think something might have happened with the shutter mechanism. I took a roll for 120 TriX400 the other day in bright sun. I just got done developing the roll and have looked at it and even made a crude positive of it to be able to study what I thought might be going on.

There seems to be some kind of a triangle starting in the lower left hand/central area and expanding out to the right corner. The top of the triangle is a little curved so it sorta seems like it could be a blade problem with the leaf shutter. It's not quite in all of them. It started a little bit on the 3rd frame and then it persisted until one shot which was just a bracket of the previous shot so it was taken quickly so I assume that the leak didn't get time to expose it.

I'll probably just end up taking the photos over again with 35mm since I know that camera works well but I wanted to know what it might take to try to bleach the leaks away at least a little bit. Is there a tutorial somewhere? What I thought I remembered seeing was to use a spotting brush and dab the area a few times where you need to work on it and then put it into fix and then rinse it off and repeat until it's as good as it's going to get. Will this just work with normal household bleach? What dilution?

Thanks!!

Andrew

if anybody would like to see the problem let me know with your email. I wont' post it here since it's a little sensitive.

Don't use household bleach. Use potassium ferricyanide. and your technique is right although it is best to have the water running and be prepared to put in on the bleach area quickly. This is done before you fix by the way. Make the bleach look like a lite version of urine. ..so very dilute. Jock Sturges does this often for highlights that get into the shot when he doesn't want them. It will take some practice, though.

For some reason photographers today seldom use lens shades. While your problem sounds like a light leak, it sould also be lens flare. TLR's are particularly prone to this problem because of the fact that the front lens element is not recessed as much as is the case for 35mm lenses.

I've used Bruce Barnbaum's technique on 8X10 negs applying bleach with a small brush. For finer detail, I'll use a spot pen desgned to remove black spots from prints - I believe the chemicals are the same. I place the negative on glass sheet with light behind & keep water handy for diluting bleach running into areas I do not want to affect. After bleaching & rinsing, I then place neg in fixer, etc..

Photo Techniquest just came out with one of their little specials, this one full of articles by Barnbaum, including the one on PF bleaching. I recommend it.

cool, thanks for the resources. I'm pretty sure it's a light leak though because it's in the same spot on each of the photos where it's present. It's also in photos that would never have any flare like in shaded areas.

So if I were to use this potassium ferricyanide highly diluted I will apply it sparingly and then rinse with water every so often? Will I fix after each rinse or just at the end? Will it hurt to dilute more that what seems necessary so as to have an even more graduated effect?

Thanks!

In Barnbaum's article on correcting a defective negative, he works slowly - rinsing & fixing frequently. It's hard to determine the extent of bleach effect until after fixing, so you want to gradually remove the defect while retaining the original image "underneath".