RB67 film problem?

[johnnywalker]

I developed two rolls of FP4+ in a Patterson tank today. The roll nearest the bottom of the tank turned out fine, the top one came out completely clear. The writing Ilford puts on the film was perfectly legible however. I checked the lenses, and they are fine - although I used more than one lens for each roll in any case and never really thought the lens(es) were the problem. This was my 77th and 78th rolls through a camera bought new by me, and it's never happened before. but I'm wondering if I could have made a mistake in loading the film? I'm not even sure it's possible to mis-load the film, but I'm clutching at straws here. I didn't notice anything unusual when advancing the film between shots.

I'd be most grateful for any ideas. The film holder (same one for both rolls), camera and lenses seem to be functiong fine, and I'm sure the darkroom work wasn't at fault, so it must be something I've done.

 

[polyglot]

Did you leave the darkslide in? I think it is possible to load the film backwards so that the paper is between it and the lens, but you'd probably not see the START arrow.

 

[MattKing]

Any chance you developed an unexposed roll?

If so your other, exposed roll is hiding somewhere .

Do you know if the problem free roll was exposed first or second?

Is there any chance the darkslide was in part way - enough to block the light but not enough to engage the interlock?

Did you have the mirror lock-up set to on on the lenses?

 

[revdocjim]

I can't think of any other explanations. If the dark slide was inserted but pulled out just a bit it would allow the camera to function normally. Also developing an unexposed roll could be the cause, but I would think you would have noticed that when loading onto the reel. Loading the film backwards into the back seems unlikely...

 

[rince]

If you were able to see the frame markings on the film, the development was fine, but the role was unexposed.

 

[noacronym]

Hasselblad addressed this problem. A Hasselblad will not trip with a darkslide in anywhere.

 

[revdocjim]

It's not a problem, but an intentionally designed function. It allows you to test the shutter when film is loaded without exposing the film to any light! I won't go so far as to say that Mamiya addressed the Hasselblad problem, but it is a useful function.

 

[Shawn Dougherty]

Any chance you developed an unexposed roll?

If so your other, exposed roll is hiding somewhere .

Do you know if the problem free roll was exposed first or second?

Is there any chance the darkslide was in part way - enough to block the light but not enough to engage the interlock?

Did you have the mirror lock-up set to on on the lenses?

This covers everything I can think of...

What camera model is it? RB67 Pro, RB67 ProS, or RB67 ProSD?

Frustrating! Hope you can get it figured out.

Shawn

 

[johnnywalker]

It's a RB67 Pro SD
I always pull the darkside out completely, so that wasn't it.
I always use the mirror lock-up.
The problem film was loaded first, a few weeks ago. I just finished it that day then loaded the one that turned out ok.
I got a sick feeling when I read Matt's suggestion that I might have developed the wrong roll, but that wasn't it.
I must have somehow loaded the film wrong. Now I'm thinking I should check all 3 of the loaded magazines.

 

[MattKing]

I always use the mirror lock-up.

Johnny:

I think this is where your problem is. For some reason, the shutters in the lenses didn't open for your shots on that roll.

It could be a problem with the cable release you were using.

Are all your lenses K/L lenses?

 

[johnnywalker]

Matt, all 3 lenses are K/L lenses, purchased new by me. I tested the lenses with and without the mirror lock-up, and could see the shutter opening each time. However, you might be right about the cable release. I'll re-do the test with the other cable release.

 

[polyglot]

If the shutter doesn't fire, then (AFAIK), the camera cannot be recocked; at least that is the case with the RZ. So if the camera seems to be working, the lens is probably firing. Whether it's firing with the right shutter speed is another matter...