Yikes! Negative problem

[Cheryl Jacobs]

David, it's a Bronica SQ-Ai. If it's a light leak, I'd expect it to happen a lot. I think I'll shoot a test roll and see what happens.

Here's another thought (because I'm still puzzled) -- could it be a problem with the chemistry itself? I'm pretty careful, but maybe it was weak or I didn't mix it well enough?

Hmmmm....

 

[glbeas]

Cheryl if your camera is one of the older vintage like a Mamiya C330 it may be the seals are going out on the back, might even happen on a modular back like Bronica and Hassys have. 120 film wouldn't show this effect until the seal is nearly falling out of the camera but 220 without the backing paper is vulnerable to the slightest leak in the seals. My old TLR had this problem and only showed up when the camera was at rest in a bright area. Rapid shooting usually never showed anything. It got fixed pretty soon after the discovery of the defect and never had a problem afterwards.

 

[glbeas]

Ah, finally saw the last post. SQAi backs are pretty easy to change the seals in and you can order the seal material fairly cheaply from Tamron. If you take it to a repair shop expect to pay an exhorbitant rate for this work. Peachtree Camera wanted to charge me $80 to do this, thier excuse was the seals were expensive. I got enough from Tamron to do all eight of my backs for $20. Heh!
Also if the film is not being wound tight enough in the back you can bend the little tensioner springs out a bit and will fix that.

 

[David Vickery]

Did you ever have the small tank resting on its side during any stage of processing??
It no longer sounds like a camera problem--from what we can see of the banding it seems too descrete and uniform to be a light leak and a leaf shutter could not cause this either. It really looks as if the tank was resting on its side at some point during processing. It wouldn't take much time to cause this if the film was on its side and not completely covered at all times.?

 

[Cheryl Jacobs]

David, no, it wasn't resting on its side at all. Thinking through it, If it had been on its side, considering the way the negs load onto the reels, the banding would've been vertical, rather than horizontal. I'm really at a loss for this one.

Could it be a problem with agitation? I do the standard Ilford-prescribed ten-second agitation per minute. Usually I invert four times during those ten seconds. Never had a problem before, but could that have anything to do with it?

 

[David Vickery]

How do your negatives load onto the reals? Doesn't the film travel vertically in the Bronica film holder? Your image is oriented vertically with the length of the film right??

 

[dr bob]

David, no, it wasn't resting on its side at all. Thinking through it, If it had been on its side, considering the way the negs load onto the reels, the banding would've been vertical, rather than horizontal. I'm really at a loss for this one.

Could it be a problem with agitation? I do the standard Ilford-prescribed ten-second agitation per minute. Usually I invert four times during those ten seconds. Never had a problem before, but could that have anything to do with it?

You stated that you have delveloped many 220 rolls using the identical techniques and materials? After hearing the details, I would have to conclude that the problem was a chemical one brought about by some unintentioned modification in technique and/or handling.

Here are some possible senerios: 1) The film was loaded properly but there was sufficient displacement in position to set up a condition where the developer was depleted in areas where the film layers were at closest proximity. Agitation in this case was just not sufficent to replace depleted developer. 2) The film was properly loaded but the developer was not entirely uniform due to (a) undesolved patriculate from a recently made up solution, or (b) dissolution of developer prior to loading due to temperature change of the stock. 3) Same as 1) except agitation caused too rapid development in the close areas.

Seems a little conflicting doesn't it? I use a modified agitation technique which I developed over the years: My technique is to invert three times, rap _hard_ three time to prevent air bells, then let it rest for a quiet minute. I do mostly 120 in a ss tank and reel and adopted this technique after recieving "bromide drag" in a 35mm reel (PXP, I think).

Truly, dr bob.