4x5 edges less development with Jobo CPA2 and 3010 drum

[Jordan]

I am getting an almost perfect 1/16" line of "lightness" (when positive) that practically mimics the natural borders of the film, most often only the long edge that runs perpendicular to the notch code. I have no idea how it is happening. I am using nice toyo film holders and developing in a Jobo 3010 expert drum on a CPA2 processor using reverse at one of the higher speeds. Anyone ever have this issue? Could it ever be some strange drying issue as I was using one of those gravity works film washers with the basket and the automatic fill and dump unit? Thanks in advance for any and all suggestions.

[Ed Richards]

Why not wash in the Jobo, film is really fast to wash. See if that helps. Then reduce the speed of rotation to the lowest setting. See if that helps. By lightness do you mean blank, or just lighter?

[Jordan]

It is only slightly lighter not even close to blank, but noticeable when printed even. They can be cropped out quite easily as they are only along the edge, but I would like to alleviate the issue all together. Does slowing the Jobo's rotation help in such an instance? Thanks.

[tgtaylor]

Sounds like fog to me.

You should be using a speed setting of "4" when using the 3010Expert Drum but a different speed would only effect the overall develpment and woldn't cause the problem you are describing.

[Jordan]

I actually should have said "an almost perfect 1/16" line of "DARKER" (when postive). So it most likely wasn't fog.

[dsphotog]

How sharp is the edge of the line?
Is it on the same place, and on all negs?
If so....
I'm wondering if it's in the camera, like a shadow of the bellows, perhaps sagging a little,
that would show most when using some lens rise.

[Andrew O'Neill]

Expose a sheet of film in your camera. Develop it in a tray with constant agitation. If the line isn't there, then it's your jobo, me thinks.

[vinny]

I've not seen that issue with my 3010 drums. Doesn't sound like a jobo issue to me. I use speed 4 as well. Is the film loaded with both long edges in between the raised ridges? Also, don't push the film down past the top of the drum. That's what jobo recommends.

[Jordan]

It's strange because I always had great results with the drum spinning only in one direction on a motor base till I picked up my CPA2. Could the speed and reverse have anything to do with this? It is strange that it is along the long sides that are up against the ribs in the drum. Thanks thus far.

[dsphotog]

I wonder if putting film in the drum emulsion side against the drum, by mistake, could cause this.
Can you post a pic of the negs?

[Bruce Watson]

Does it *always* happen, every single sheet? If not, does it happen to every single sheet in a run? If not, it's not the process.

I've had a line of increased density show up on the negative when working in bright conditions -- the film holder's film hold-down rail itself was quite shiny and reflected some additional light onto the edge of the sheet. Perfectly straight line, almost exactly matching in width, the depth of the face of the hold-down rail (which is 90 degrees to the surface of the film). The "fix" was some fine sandpaper to take the sheen off that surface. Poof! Problem went away.

If it's really a line of *less* density on the negative... IDK.

[Andre Noble]

I would guess he uses the gravity works for washing as the Jobo is not archival wash - this per museums. I had one, could never use it because the Los Angeles tap water is incredibly hard, and ruins films.

As for rotation speed, one should always use the very slowest rotation speed as possible to develope film in the Jobo. I bet a too fast rotating drum is the cause of the lines.

[Jordan]

So like I said it is actually a light line in the negative thus causing a darker line in the print. I am really confused and am gonna process a test batch today on speed 4.

[Andre Noble]

At a high speed rotation the ridges in the 3010 would cause uneven development problems that you probably won't encounter at high speeds with the 3006 drum.

I really do not know why you want any speed other than the very slowest roatation speed when processing sheet film in the 3010 in light of these ridges.

[Jordan]

Ok so after processing another batch and doing in camera tests, I am lead to think that maybe in my haste I did put a few new negatives base-side inward in the jobo by accident. Someone earlier in the thread suggested this and I think they may be onto something. Do any of you really think it would be possible to have an otherwise perfect negative minus this line of less negative density by making such a mistake? Let me know and as always thank you all for all your help.

[Greg Blank]

That drove you crazy, I remember your call...even I couldn't figure that one out ;)


Does it *always* happen, every single sheet? If not, does it happen to every single sheet in a run? If not, it's not the process.

I've had a line of increased density show up on the negative when working in bright conditions -- the film holder's film hold-down rail itself was quite shiny and reflected some additional light onto the edge of the sheet. Perfectly straight line, almost exactly matching in width, the depth of the face of the hold-down rail (which is 90 degrees to the surface of the film). The "fix" was some fine sandpaper to take the sheen off that surface. Poof! Problem went away.

If it's really a line of *less* density on the negative... IDK.

[eman]

Andre, could you expand upon the lack of "archivalness" in the Jobo processor that you mention? Although I do many more washes, I was told by a Kodak professional helpline person I could get by with 4 rinses after hypo clearing! I still don't believe them on that one.:)
Thanks
Eric


I would guess he uses the gravity works for washing as the Jobo is not archival wash - this per museums. I had one, could never use it because the Los Angeles tap water is incredibly hard, and ruins films.

As for rotation speed, one should always use the very slowest rotation speed as possible to develope film in the Jobo. I bet a too fast rotating drum is the cause of the lines.

[Michael Szedon]

Sounds to me like the edges of the film are getting more developed than the middle. This happened to me when developing cut film using hangers and a tank...that's why I tray develop my cut film now, problem gone.

[Ed Richards]

> I would guess he uses the gravity works for washing as the Jobo is not archival wash - this per museums.

I think the museums are thinking about paper. Film, esp. modern film like Tmax, is really easy to wash. The backing is impervious and absorbs nothing, and the emulsion is so thin that the diffusion time has got to be seconds or less for stuff to get out. Three changes, the first two filtered and the last distilled should be more than enough, as long as you drain the tank completely between washes. No reason to use Hypo clear.