Issues with exposures in bright light

Ulrich Drolshagen · Jul 22, 2009

Hi all,

I occasionally have annoying issued with exposures with my Chamonix as in this frame:

This is a negative scan with an Arcus 1200. I am not good at scanning negatives but I hope it serves the purpose.

Details: Cham. 45N-1, f9/360mm Apo-Ronar, HP5+ EI400, D76 1+1 9'30" rotation. Jobo CPE2, Multitank 2553, frameholder is the one with the wings to clip in after loading. The tank was filled with 560ml. There were six frames in the holder two of them have these stripes. The other one is the same scene but taken with a f5.6/150mm Sironar-N. The stripes on this are less obvious. I don't know where these two frames were loaded but it is very likely that they were in opposite positions in the frameholder.
What is obvious for me is, that the stripes are very regular. So to me issues with pouring in or out the developer seem very unlikely.

Has anybody seen something like this and can explain it to me?
I always make to exposures of the same scene. So I can repeat the development. If this is an issue in the process I'd much like to know how to avoid it.

Ulrich

Anscojohn · Jul 22, 2009

Do you think it is an exposure problem unrelated to bright light exposure or a problem with the roto processing? My guess would be with the roto processing?

Ian Grant · Jul 22, 2009

It's nought to do with the exposure, it's a process problem.

Can't help furtheras all my tanks are inversion type

Ian

Ulrich Drolshagen · Jul 22, 2009

I don't know. The stripes are orthogonal to the direction of rotation. I can not think of anything producing such regular stripes. With a focal plane shutter I would think of banding but it was taken with a between the lens shutter. I really don't know. But if anyone knows the reason, I'd much like to know it before I process the backups if it is related to the developing process.

Ulrich

Ian Grant · Jul 22, 2009

had to look up "Orthogonal" and the meaning was interesting "Not pertinent to the matter under consideration"

Actually it looks as though the reel with the sheets of film isn't rotating properly causing the banding, could be slipping.

Ian

Sirius Glass · Jul 22, 2009

Anscojohn said:
Do you think it is an exposure problem unrelated to bright light exposure or a problem with the roto processing? My guess would be with the roto processing?

My thoughts too.

Steve

Ulrich Drolshagen · Jul 22, 2009

Ian Grant said:
had to look up "Orthogonal" and the meaning was interesting "Not pertinent to the matter under consideration"

As you can see, my knowledge of the English language is improving

Actually it looks as though the reel with the sheets of film isn't rotating properly causing the banding, could be slipping.

Ian

Thanks, this is the most convincing approach so far. I just looked into this. The foot of the middle tube and the counterpart in the tank have notches thus that the spool is fixed. There are two ways to put the spool in. In one position there is a slip of about 20° in the other the slip is about 5° to 10°.
The tank itself is coupled to the CPE2 by a magnet. This may be another cause of slip if the rollers are causing so much friction that the tank has a slight slack as the direction of the rotation changes. This may cause irregular development square (!) to the direction of rotation. What I can not see is the cause of the very regular recurrence of the stripes.

Ulrich

Pupfish · Jul 22, 2009

Six sheets in a 2509 reel can sometimes be two sheets too many if your film base isn't stiff enough to prevent the sheets from touching when wet. Were they stuck together when you pulled them out? One to the inside+ middle slot empty+ one to the outside might cure this.

BrianShaw · Jul 22, 2009

Ulrich Drolshagen said:
As you can see, my knowledge of the English language is improving

I love that word and use it often. But, then again, 4 out of 5 statisticians do also!

bdial · Jul 22, 2009

If you are using the slow speed, try it on fast, which is Jobo's current recommendation.

That took care of the uneveness problems I was having, but I didn't get patterns extending across the whole neg. as you've shown.

If you don't mind using around a liter of chemistry, you could try a few sheets using inversion.

Bruce Osgood · Jul 22, 2009

The repeating of the problem across the film would suggest to me it is not the camera but the processing. Don't have an answer but I stay away from 6 4X5 sheets in the Jobo, 4 max and I don't use the wings.

Ulrich Drolshagen · Jul 23, 2009

@pupfish
The sheets didn't stick together. But I'll try with just two sheets just to be sure. I don't remember having the problem when I had developed just two sheets.

@bdial
I know of Jobo's recommendation. I alway use the high speed. I think, the tank is too small for inversion. I would have to fill it completely so there would be no air in it. Inversion would not mix the chemicals sufficiently then.

@Bruce
As I understand it Jobo invented the wings as an improvement to prevent uneven development. But I will try with fewer sheets in the reel.

Thanks for your help so far. I will try the next sheets today. I hope to get hold of the two sheets in question first (I don't know exactly which they are in a stack of sheets. So it can take some time to present results)

Ulrich

polyglot · Jul 23, 2009

Orthogonal can also mean "at 90 degrees to". A more general definition would be "does not correlate with". Anyway.

My only guess as to the problem at hand is that if it's not slipping in the drum, it could be a standing wave in your tank, i.e. due to the way the developer flows over the film, you might get ripples and/or some parts of the film might get more agitation. I don't do LF myself though so don't really know. I wouldn't expect it to be film stuck together - I've done that accidentally while putting 2 rolls of 120 in a spiral and not pushing the first one in far enough - one of the films will come out completely undeveloped and the other with an undissolved milky backing that requires a re-fix.

Mick Fagan · Jul 23, 2009

Ulrich, it is possible that with you using precisely 560ml of solution, you are just covering your inner films.

I use the 2523 tank with 1 reel and four films, Jobo say 270ml, trust me when I say this just covers the sheets with a very small margin for error.

Is your processor dead flat?

Is your solution quantity exactly 560ml, or is it a tiny bit under?

If either of these are not exact, then you haven't allowed enough room for error. Jobo do seem to give very little room for error, which is fine, but one has to be careful.

I use 300ml instead of 370ml with my smaller tank, with your tank I would use 600ml.

Looking carefully at the sample you have shown, those lines really look like wave lines. I'm purely guessing here, but it seems to me that it may be possible that the developer solution is just breaking over the inner films and it is running over in small waves.

I'm not familiar with the 2509 reels with the wings, my reel doesn't have any wings as they weren't invented when I bought my reel and tank.

Do you think it is possible that the wings may be just causing enough surface turbulence, to create small waves?

When I first started rotary processing I was unsure of just how close the Jobo solution requirements were to either be dead correct, slightly under, or slightly over.

I measured water to the correct solution capacity stated, very carefully, placed the reels(s) in the tanks without film, poured the water in whilst the tank was in the inversion position. Then I covered the top of the tank with a clear cling film (Klarsichtfolie?). Then I placed the tank on its side on a checked level surface.

The results were interesting, basically there is no room for error.

From then on I generally have always gone up slightly with solution quantity, especially with the first bath as the tank is bone dry and there is no used solution from the previous bath remaining.

Using a Jobo lift as I do, there is dependent upon the tank type and size, different amounts of carry over solution. From about 14ml to 25ml on the bigger tanks. This amount by the way, is pretty close to the leeway you have with solution capacities in Jobo tanks, in my experience.

Mick.

2F/2F · Jul 23, 2009

I hope you can salvage these, because I think that is an outstanding picture.

Lee L · Jul 23, 2009

Jobo also recommends a 5 minute presoak last I heard, in part to make times more similar to small tank inversion processing, but also to make development more even.

Lee

bdial · Jul 23, 2009

For inversion use, you would fill the tank and use it in the same manner as a roll film tank, and not in the Jobo. It takes a lot of chemistry, but it works just fine, there is no problem in the developer mixing.

Ulrich Drolshagen · Jul 23, 2009

May be I have identified the culprit.
The tank hast fillets (I don't know whether this is the right term for it) on the inside wall which correspond perfectly to the three stripes in the middle of the sheet. I have loaded the reel, according to Jobo's recommendation with the emulsion side out. If the frame was the outermost one, there may have been turbulences alongside these fillets which cased over development, which in turn makes lighter stripes in the positive.
I will load the reel in future with the emulsion side in.

If I fill the tank to the brink, I need 1200ml. Filling it with 600ml should fill the tilted tank in the processor up to the tube in the middle. So 270ml should be more than sufficient to develop a completely filled sheet-reel as it only uses about 10mm or so of the outer part of the reel. With 560ml I should be ok in any case in this respect.

I keep you informed about how things will go on. Thank you all for your suggestions.

Ulrich

Lee L · Jul 23, 2009

Ulrich Drolshagen said:
I have loaded the reel, according to Jobo's recommendation with the emulsion side out. If the frame was the outermost one, there may have been turbulences alongside these fillets which cased over development, which in turn make lighter stripes in the positive.
I will load the reel in future with the emulsion side in.

My understanding was that emulsion side should always face the center core of the reel, and film base should face outward. Hope you've found the solution. Very likely the case if the pattern matches the tank

Ribs might be a better English term than fillets.

Lee

Ulrich Drolshagen · Jul 23, 2009

I just developed the last sheets of the lot two by two. They are all ok. I used the middle slot with the emulsion side pointing inward and attached the wings. In future I will load four sheets at maximum with the emulsion pointing inward and leaving the slot in the middle free.

Ulrich

Bob Carnie · Jul 23, 2009

This problem is the road rut problem Elevator experienced for awhile with Jobo tanks.
We solved this problem by manually inverting the Jobo tanks in the first 20 seconds after developer was added.
then slap onto the Jobo and rotate.
The minus density is the clue which gives darkness on the positive image.
This problem almost singlehandely closed our film production for one month until we solved the problem

Agitation at starting stage of development with a twist is the answer we found.

Thomas Bertilsson · Jul 23, 2009

Lee L said:
My understanding was that emulsion side should always face the center core of the reel, and film base should face outward. Hope you've found the solution. Very likely the case if the pattern matches the tank

Ribs might be a better English term than fillets.

Lee

Mmmmmm..... Ribs... :munch:

Ulrich Drolshagen · Jul 25, 2009

So I got it right at last.

It is a first straight print and the scanning is not optimal. But the picture is Ok so far. Thanks again for your suggestions.

Ulrich

Issues with exposures in bright light

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