Problems with Cambo/Graflock

Hi to all!

New to the communitie I have to bother you wether someone could have made this kind of experience with his camera's back, I am at my wit's end for today.

The camera is my tiny baby, an elder Cambo SC with the Graflock back.

Since three days I have the symptoms on the neg as shown with the attachment. The marked upper part is an area of less densitiy, one of the smaller sides is more sharp and the other a bit more fuzzy. The difference in density is about one stop and turns with the rotating Graflock while changing from portrait to landscape. Something seems to hang into the optical path.

First thought was it could be with the new opened package of film. To exclude it I tried two other packages, the same.

Same procedure with changing the lens.

Examination of the camera/back didn't show anything.

Even changing the bellow ...

Changed front to back and vice versa: nothing.

I even tried to find an explanation for it couldn't be only something "shading" the normal way: PErhaps it could be, every other part of the neg could be over exposed except the mentioned part (1 cm in height and 6cm in width) would be the only one which would have got the right exposure ... checked the camera: no leaks.
And as I work strictly with the zone system also for the test shots, the mentioned "stripe" is definiteley the wrong exposed ...

Any hints?

Thanky you all in advance

Horst

Ups

not only the camera is getting old, me too ...

Horst

Are you using a different kind of filmholder than you've used in the past? It sounds like the filmholder isn't going in all the way if you're having a sharpness problem of the sort you describe, and then the obstruction would be connected to that.

I think on some Cambo 4x5" cameras there is a metal bracket on the back that is used to hold a cable release that connects to an automatic shutter system and stops down the diaphragm when the filmholder is inserted, and this bracket does not work with certain types of filmholders, like Grafmatics, and perhaps the Readyload or Quickload holders. Some people who don't own the automatic shutter system and never intend to own it just grind off the bracket.

I'm a little unsure from your description, but another problem could be a bellows obstruction, but if you're getting this in both the vertical and horizontal orientations it wouldn't be that, and it wouldn't explain the sharpness problem in any case.

Hi David,

Thank you for your reply.

No, nothing changed! I am using nearly new filmholders with this nearly standard back, 8 pieces Fidelity.
It's a kind of Vodoo, the cam slept two day in "her" box after some negs I could develop perfectly, and "she" was out of reach of kids and dog;-)

The stripe is always on the upper side of the film, equal how I rotate the back.

And: it is exactly as sharp as the other parts of the neg ... the part is simply under exposed.

Just thinking ... I fear I have to take a look on my tank wether the stripe will fit somewhere on it ...

Horst

Ackward, ashes on my head!

Surely I have found the solution ... it's the solution;-)

As I haven't used my tank (one of those higly flexible Doran for 4x5) for a long time I assumed it still needed 1500ccm of developer ... far away! 1690ccm is the volume! The difference between the negs I made a few days ago is I used a tray to develop.

So with the tank it misses round about 1cm with the height of the developer ... and the fully developend egdes on the top of the neg: capillary attraction.

That's my theory and has to be proofed now

Thank you again

Horst

Dopey ... that's it. Please, don't tell anyone.

The theory was right, the mark perfectly fitted ... and with the right amount of fluid the negs are perfectly developed.

Shame on me again

horst

TheMissingLink said:

Dopey ... that's it. Please, don't tell anyone.

The theory was right, the mark perfectly fitted ... and with the right amount of fluid the negs are perfectly developed.

Shame on me again

horst

Click to expand...

We won't, you just did. We all make dumb mistakes occasionally.

tim in san jose