Question about Jobo/Rotary Film Processors

antmar · Mar 14, 2016

I really wonder why the letters of the film are inside your frame? I think that your problem starts by the fact that your camera uses more film than the usual of a standard frame and very close to the borders of the film. Reels use these film borders to hold it in place as well and this part is often underdeveloped.
I can also see this underdeveloped effect at the lower right side as well but it is less obvious due to the letters.
I also want to add that from my experience leveling in rotary development can never give such a clear and straight line in the whole film length but a more degrade pattern to the film width usually more obvious at the first film frames (last loaded in the reel in 120). This type of clear line could be found in stand development or better in semi stand but not in rotary and when they happen they have nothing to do with level or chemical volume but they are probably from interference with the reels.

RobC · Mar 14, 2016

can you see these lines with the naked eye? They're not scanning artifacts are they?

Is there something odd about the film mask in the camera such as having shiny edges which reflect light onto film edges?

Neal · Mar 14, 2016

Dear bvy,

I have used Jobo rotary tanks for the last 17 years and have never run into the issue you've noted. If that was a problem inherent to the Jobo system the system would have been abandoned by now.

Good luck,

Neal Wydra

RobC · Mar 14, 2016

But these are paterson tanks being used on a roller base and not jobo tanks on a jobo processor. Not saying thats the problem but something is not right.
Another point worth mentioning which could be a contributing factor is that the paterson center column can freely rotate. i.e. The tank rotation does drive it round directly and it relies on friction. With all that fluid in the tank there is plenty lubrucation to reduce friction to very little so the assumption that reels are rotating at same speed as tank is not a valid one. They may be or they may not be. I think the jobo tanks drive the center column around so its only friction between column and reel that is needed to rotate reels.

RobC · Mar 14, 2016

But I think most likely casue is chemical contamination from the reels. make sure you wash them really well between usage. residual photoflo is known to cause problems of this kind. If it were fix you'd expect them to be underdeveloped and not over developed. But who knows what you used the tank for last time before this dev sequence.

mrred · Mar 14, 2016

Well, I have the same setup......with a twist. I have a stainless steel tank I put inside the paterson. I have a 5 degree slope to keep everything in place. I prefer my hughes reels. I've been developing this way for about 5 years now. Since you are exposing down to the edge, it may be a better way to deal with it.

Note that my base is not reversible and I make sure the real is positioned that the spiral scoops up the developer.

I develop 1 reel at a time and only use 150ml solution with no issues. I don't put the stopper on the cap of the ss tank.

bvy · Mar 14, 2016

RobC said:
can you see these lines with the naked eye? They're not scanning artifacts are they?

Is there something odd about the film mask in the camera such as having shiny edges which reflect light onto film edges?

I can see them with the naked eye. The film in the 8x10 holder has no mask.

RobC said:
But I think most likely casue is chemical contamination from the reels. make sure you wash them really well between usage. residual photoflo is known to cause problems of this kind.

I have used Photo-Flo on the reels, but I'm using a brand new reel for these experiments that hasn't been exposed to Photo-Flo.

antmar said:
I also want to add that from my experience leveling in rotary development can never give such a clear and straight line in the whole film length but a more degrade pattern to the film width usually more obvious at the first film frames (last loaded in the reel in 120).

That makes sense. Even so, I wonder if the problem is happening when the film is pulled up and out of the solution. Is residual developer flowing to one side during this part of the cycle? Are the tracks of the reels retaining developer? I'm wanting to try it with a mostly full tank and compare the results.

RobC · Mar 14, 2016

maybe the new reels had some grease or oil on them from the manufacturing process?

Give them a thoriugh clean and run a test film through them. If problem has disappeared then you can just put it down to being unlucky and in future make sure reels have been properly washed after every use.

MattKing · Mar 14, 2016

My roller agitator reverses automatically throughout the process. I know that you said that you are adding some manual agitation to the process, and reversing the tank on the agitator from time to time. Maybe you can increase the frequency of that.

At the risk of releasing the APUG floodgates, I should mention that I always start with a three minute water pre-soak on the roller agitator. If by chance your problem is due to the film sticking to the reels, a pre-soak might help.

ic-racer · Mar 14, 2016

bvy said:
For those of you with Jobo or Unicolor film processors, I'm curious -- do the film edges get overdeveloped? I've been experimenting with rotary processing on a Unicolor (reversible) motor base, but I'm using regular Paterson reels either in a tank or a Unicolor print drum. This works just fine -- good even development -- except that the edge of the film that sits in the tracks of the reel gets over developed (see contrast- enhanced picture). Since I'm doing some work where the film gets exposed all the way to the edge, this is a concern. It also creeps into the edges of regularly exposed frames as well. I've only experimented with 120 thus far.

Is there something special about Jobo or Unicolor reels such that this isn't a problem? I've looked at pictures, and I'm not seeing it. Or is it just the nature or constant rotary processing and agitation? Thanks.

View attachment 152403

Not much discussed here on APUG but I think the Jobo plastic reels are of superior design. I did extensive testing of Jobo, Patterson, Beseler, generic and metal reels for rotary processing when T-max developer came out in the 1980s. The Jobo plastic 1500 reels were the best. I'd get one and compare your results side-by-side with film from your existing reel. You may get the same good results I get with the Jobo reels. I have been using the Jobo 1500 reels for all my rollfilm processing (Minox to 120) ever since.

bvy · Mar 14, 2016

MattKing said:
My roller agitator reverses automatically throughout the process. I know that you said that you are adding some manual agitation to the process, and reversing the tank on the agitator from time to time. Maybe you can increase the frequency of that.

Mine is also auto-reversing. For variety, I tried putting the reels directly into an 8x10 print drum. They fit nicely -- there's not enough clearance for them to fall on their sides, but they have room to roll, and as the drum rotates, the reels tumble over the slots that hold the paper. I thought this extra bit of turbulence might break up the flow, but I still got the overdeveloped edges. I contemplated some way to introduce sine wave agitation, but at some point, it's more work than reward.

ic-racer said:
Not much discussed here on APUG but I think the Jobo plastic reels are of superior design. I did extensive testing of Jobo, Patterson, Beseler, generic and metal reels for rotary processing when T-max developer came out in the 1980s. The Jobo plsastic 1500 reels were the best. I'd get one and compare your results side-by-side with film from your existing reel. You may get the same good results I get with the Jobo reels. I have been using the Jobo 1500 reels for all my rollfilm processing (Minox to 120) ever since.

Thanks for chiming in. Did your experience with the other reels produce results like the ones I'm getting? The Jobo reels don't look much different than the Paterson reels I use. I'd hate to get them and have the same problem. But I may try. It gets back to my original question about the reels being specifically designed for constant rotary agitation.

Photo Engineer · Mar 14, 2016

I think it is a matter of uneven agitation. IDK how to improve it with your equipment, but a bit of prewet and some hand agitation might help before you put the drum on the rollers.

PE

Sirius Glass · Mar 14, 2016

RobC said:
But I think most likely casue is chemical contamination from the reels. make sure you wash them really well between usage. residual photoflo is known to cause problems of this kind. If it were fix you'd expect them to be underdeveloped and not over developed. But who knows what you used the tank for last time before this dev sequence.

Jobo strongly recommends that the film be removed from the tank before using PhotoFlo. Specifically do not put the reels in PhotoFlo.

RobC · Mar 14, 2016

MattKing said:
At the risk of releasing the APUG floodgates, I should mention that I always start with a three minute water pre-soak on the roller agitator. If by chance your problem is due to the film sticking to the reels, a pre-soak might help.

The lines on the negs are OVER DEVELOPMENT (or over exposure). If film sticks to reels you would expect under development.
You can see on one neg that there is lighter line, then it goes dark which then fades into lighter neg background area. That suggests checmical contamination to me more than anything else.

ic-racer · Mar 14, 2016

bvy said:
M Did your experience with the other reels produce results like the ones I'm getting?

I don't recall having such an even demarcated density like that from processing, so I can't offer a suggestion. The only negatives I have like that are from an old vertical FP shutter camera in which the the second blade sometimes sticks a little on the way down. You wouldn't have that problem.

MattKing · Mar 17, 2016

bvy said:
For those of you with Jobo or Unicolor film processors, I'm curious -- do the film edges get overdeveloped? I've been experimenting with rotary processing on a Unicolor (reversible) motor base, but I'm using regular Paterson reels either in a tank or a Unicolor print drum. This works just fine -- good even development -- except that the edge of the film that sits in the tracks of the reel gets over developed (see contrast- enhanced picture). Since I'm doing some work where the film gets exposed all the way to the edge, this is a concern. It also creeps into the edges of regularly exposed frames as well. I've only experimented with 120 thus far.

Is there something special about Jobo or Unicolor reels such that this isn't a problem? I've looked at pictures, and I'm not seeing it. Or is it just the nature or constant rotary processing and agitation? Thanks.

View attachment 152403

I just realized from your post in Optiken's Unicolor thread that the film tany you were usjng wasn't a Paterson film tank.

When I read "Paterson reels either in a tank or a Unicolor print drum" I interpreted it as meaning a Paterson film tank or Unicolor print drum.

Tanks and reels work together when it comes to flow patterns. I think the mismatch may be your problem.

bvy · Mar 18, 2016

MattKing said:
I just realized from your post in Optiken's Unicolor thread that the film tany you were usjng wasn't a Paterson film tank.

When I read "Paterson reels either in a tank or a Unicolor print drum" I interpreted it as meaning a Paterson film tank or Unicolor print drum.

Tanks and reels work together when it comes to flow patterns. I think the mismatch may be your problem.

I used Paterson reels in a Paterson film tank several times. I switched to trying the reels in a print drum when I was getting unsatisfactory results.

Question about Jobo/Rotary Film Processors

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