Aggie, yes, I'm extremely conscientious about my developing, including tapping out the air bubbles. Never had a problem until now.
Cheryl, you say this negative was the outermost negative on the reel. Could it somehow have stuck to the side of the tank during development, causing these bands?
Anything's possible, although the negs were spooled properly when I took them out of the tank. Also, there were negs with that same problem on the inside of the spool as well.
I would also look at the possibility of a light leak. While the film is in camera, since there is not any banding outside of the image areas. Not rolling it tight enough would cause the banding to be out side of the image area also. I think static would have a different shape entirely. What kind of camera is it? It looks like it could be caused by a jumpy, focal plain shutter.
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?
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.
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.
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.?
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?