Overexposed Negative Egdes

[Peter Williams]

Overexposed Negative Edges

I have been getting what seem to be overexposed edges on my negatives. I thought that it might be a problem with the way I loaded the film onto the reels, but it does not seem to happen with film from other cameras. Any suggestions are appreciated.

 

[photobackpacker]

What do the edges of the film look like. Are you seeing any density there or are they clear?

 

[Peter Williams]

The edges are clear - the film type and mfg are clearly legible on the edges.

 

[Bob Carnie]

hi peter
This looks exactly like a problem I was having with 120 film non pyro development on the jobo.How are you processing the film and is it 120 format.
Definately looks like development problem. I will go further when I know what film , how you processed and what developer.
bob

 

[Gerald Koch]

What agitation scheme do you use?

 

[Peter Williams]

THis particular film was Knoica IR 750 processed with D-76 (1:1). Used 8 1/2 minute development with 5 secs agitation every 30 sec. I got nearly the same result with TMax 400 processed in D-76 - not sure of development times, but it was from Kodak's D-76 time sheet. Both films are 120 processed in plastic tank with plastic reels.

 

[NER]

Looks like a light leak to me.

 

[Peter Williams]

Looks like a light leak to me.

Would that be a light leak in the processing container, or camera back?

 

[Gerald Koch]

Your plastic tank may not be completely opaque to infrared radiation. You really need to process IR film in a metal tank.

 

[Andy K]

I got negs exactly like that when I first got my OM10. One light-seal kit later and all was fine.

 

[Ole]

I do all my processing in plastic tanks, sometimes even in sunhsine. I have never seen any sign of light leaks in these, not even with MACO IR 820/400 or Kodak HIE. I find it very unlikely that this is what has happened hee.

This looks more like overdevelopment to me - could the agitation have been too vigorous? See if the contrast is higher near the edge, or if it's just added all-over density.

 

[Bob Carnie]

This is looks like a laminar flow problem with development. wheras the middle section of the film is not recieving the same amount of fresh chemistry as the outer edges. I have had this problem and it usually is more pronounced on the inner 120 film on the reel than the outer film when loading two up. As well my problem was on a jobo system that rolls the film back and forth on the rollers.
We found the solution to this problem was to take the drum off the machine immediately after the first rotation and manualy twist the container to break the direction of the dev. put back on machine, one rotation and then take off again and manually rotate. This is now our set proceedure for all 120 film on the jobo. If we do not do this as our operator did last week we get the minus density going the length of the film as your photo shows.
The first 15 seconds of development are critical to avoid this problem. It took us quite a long time to solve this problem and it looks like you have the same minus density in the middle of the film like ours.

 

[kaiyen]

What agitation pattern (physical motion) do you use? Do you rotate while inverting? Just invert?

I got a similar effect with a few rolls of 120 lately. Turns out that I was putting in too much developer, and not sufficiently disrupting flow. Filling the tank to the brim made it harder to get good movement throughout the tank - leaving some space in there lets it really move around.

I was just inverting - combined with the very-full tank, I wasn't getting as much movement of fresh developer to the middle as I was to the edges, increasing density on the edges.

I have never gotten fogging from my plastic tanks, either.

allan

 

[aj-images]

Try gaffers tape around the back of the camera.

 

[Peter Williams]

What agitation pattern (physical motion) do you use? Do you rotate while inverting? Just invert?

I have one with the rod that twists to agitate.

 

[David A. Goldfarb]

Presuming you have a cap, try inversion. I also think it's a development problem. I think what's happening is that the physical design of the reel is causing more turbulance close to the reel when you apply the twisting motion, so the edges are getting more development than the center. Some film/dev combos might be more prone to this problem than others, which is why you're not seeing it all the time.

If you can't invert, or if inversion doesn't help, use a different type of tank.

 

[Peter Williams]

Thank you all for the great advice!

 

[NER]

Would that be a light leak in the processing container, or camera back?

Camera.

 

[gnashings]

I have never used IR film - so please take this into consideratin - but I am using what seems to be the same method with my 120 film, and have had no issues. I have a plastic Patterson tank that (the one I mainly use) that holds 500 ml for a single 120 roll and 280ml for a single 35mm roll. I have tried twisting the rod, swishing the dev with a circular motion of the tank (which is what I do now) and inverting - and have seen no discernable difference as long as the intervals and durations were the same. I did have marks on the edges of the negs, but they were not affecting images on the frame and turned out to be residues of liquid in the grooves of the reel, which I am now more adamant about cleaning and drying, which solved that problem.

In my humble opinion, you wrote "this does not happen with any other camera..."

Whenever a problem occurs, in any of my hobbies, I try to eliminate all the variables one by one, until I have arrived at a point where I have one set of conditins that occurs with one particular problem. It seems that in this case its : that camera + film = overexposed edges. This leads me to believe, that you have a light leak. What camera are you using? Does it have removable film backs? If so, it seems that most light leaks can be traced to the area around the dark slide, and of course the edges of the film door. I would look there first. Once you eliminate that as a possibility and have no improvement, you can worry abut the other possible causes. I have found that the simplest solution is usually the best. Hope you solve it soon,

Peter.

 

[Donald Qualls]

Look carefully at the posted image.

If it were a light leak, there would be a loss of contrast in the edges where the negative density is higher, and to my eye it appears that the opposite is the case -- which is what I'd expect if the edges of the negative were developed more than the center. That's indicative of insufficent or inefficient agitation; it's common when using swizzle-stick agitation in a non-inversion type plastic tank, where the agitation may not efficiently bring fresh developer all the way to the center of the film.

 

[kaiyen]

A couple of good threads on this topic at PN are here and here

allan

 

[Peter Williams]

Thanks for the help everyone. I ran another roll through today and developed with inversion and the negatives came out great.