XTOL: develop two rolls at a time in 1+1

[madNbad]

This is an interesting thread. My only need is for two 135 rolls in a 16oz tank but I really had no idea that film slipping on the reel during development was something to be considered. It makes sense to maximize chemistry by loading two medium format rolls end to end. Learning something new was not quite what I expected when the thread began.

 

[dynachrome]

A few things: When I use SS reels I don't have to worry about the film slipping out. I recently bought what turned out to be a no-name 1 reel (35mm) SS tank with a Kindermann top. It came with a SS reel that I was not familiar with.
The center core is wider than typical SS reels. After a little research, I found that it is a Hewes reel made for use with Jobo tanks. The wire gague is not as thick as on a regular Hewes reel but it's beautifully made. It has the teeth in the center so the film will not move. Finally, if X-Tol can't be found, Clayton F76+ or the Arista equivalent will give similar results.

 

[pentaxuser]

Thanks Matt I take it you have tried it and your continuous rotation has shown that one film does over take the other. By how much was this and was this in a Patterson tank?If it was a Patterson tanks do they have any kind of stops on the central tube that locks the movement?

If slippery film is the problem then presumably on a rotation process you'd find that even one film migrates forward. I have never tried rotary processing with anything other than C41 film but when I do I haven't noticed much if any forward motion in terms of finding the film farther forward on the reel at the end of the rotation than it was when I finished loading it onto the reel

pentaxuser

 

[pentaxuser]

With taping, if the tape comes off, the second roll might slip. Using two 36 exposure rolls in one reel, you need to go back to back. If the two emulsion sides were touching, you would have a mess.

Can you describe the sort of mess you had when the 2 emulsion sides were touching compared to the two shiny sides and what it is about the other way that prevents whatever the mess is that I hope you will describe

Thanks

pentaxuser

 

[MattKing]

Thanks Matt I take it you have tried it and your continuous rotation has shown that one film does over take the other. By how much was this and was this in a Patterson tank?If it was a Patterson tanks do they have any kind of stops on the central tube that locks the movement?

If slippery film is the problem then presumably on a rotation process you'd find that even one film migrates forward. I have never tried rotary processing with anything other than C41 film but when I do I haven't noticed much if any forward motion in terms of finding the film farther forward on the reel at the end of the rotation than it was when I finished loading it onto the reel

pentaxuser

You can't predict how much of a problem you are going to encounter - it varies.
In my case, Paterson tanks, and mostly AP reels, although I might have had it happen with a Paterson reel as well.. The Paterson core locks, and the reels can rotate freely on it, but the friction between the two seems to cause the reels to rotate with the tank and core, although the inertia of the fluid may affect that - I can't really see, because the lid is on and it is dark in there
And to confirm: it is only a problem for the development stage. I use continuous rotary agitation for all the rest, and the films seem to stay put.

 

[dynachrome]

I will try to post a photo of the concept tomorrow. I have never tried loading two rolls emulsion side to emulsion side. They would stick to each other. I did succeed in doing it shiny side to shiny side but after separating the two rolls I needed to rinse each roll separately to get out any chemistry which was sitting between the two shiny sides.

 

[john_s]

I will try to post a photo of the concept tomorrow. I have never tried loading two rolls emulsion side to emulsion side. They would stick to each other. I did succeed in doing it shiny side to shiny side but after separating the two rolls I needed to rinse each roll separately to get out any chemistry which was sitting between the two shiny sides.

Are there any roll films that have a coating on the back? I have read that some sheet films have. That would lead to a bit of a mess if they were loaded base-to-base.

 

[grain elevator]

Are there any roll films that have a coating on the back? I have read that some sheet films have. That would lead to a bit of a mess if they were loaded base-to-base.

I think all 120 films do.

 

[Philippe-Georges]

I think all 120 films do.

Yes the 120 rolls have that dark bluish-purple back coating that dissolves in the pre-wash, and when be poured out comes as a surprisingly ink dark liquid.
Normally this backing emulsion that is, among others, meant to keep the film flat during exposure (emulsion on one side might pull the film to curl), is finally fully 'taken' away by some components in the liquids during the processing.

 

[koraks]

Normally this backing emulsion that is, among others, meant to keep the film flat during exposure (emulsion on one side might pull the film to curl), is finally fully 'taken' away by some components in the liquids during the processing.

Not quite. The anti-curl emulsion on the backside remains in place on 120 and sheet film. However, antihalation dyes are generally embedded into this emulsion and those wash out. The gelatin stays put.

 

[Philippe-Georges]

Not quite. The anti-curl emulsion on the backside remains in place on 120 and sheet film. However, antihalation dyes are generally embedded into this emulsion and those wash out. The gelatin stays put.

This might be so, but when moistened AFTER processing and drying, the back side of roll film isn't that 'sticky' as the image side, but ofcourse the image bearing gelatine emulsion is thicker by far...

Anyway, processing film back to bak on one reel seems not to be that obvious, although I read in one of the 'Aperture Darkroom' books that the famous Eugene Smith was doing this with small format film.
I tried it, long time ago, and the 35mm films ware sticking rater firmly, but, I have to admit, it was Agfapan instead of Tri-X...
So I think that the back side of all film might not be equal .

I never did it again, not with 120 film nor 4"x5", I just got a larger tank which could hold more reels.

 

[koraks]

This might be so, but when moistened AFTER processing and drying, the back side of roll film isn't that 'sticky' as the image side

The degree of stickiness will depend on factors such as emulsion thickness, degree of hardening etc. The gelatin remains there because it needs to continue to serve its purpose in particular after processing - i.e. preventing the negatives from curling (too much).

35mm is different because it doesn't have this anti-curl gelatin layer on its backside. Of course 35mm film strips will stick rather firmly to each other back to back as any kind of film, sheet etc. will do, but this is unrelated to emulsions etc.

I assume given your experience you're familiar with the differences in wet properties of the non-image sides of 35mm film vs. larger film formats.

 

[pentaxuser]

You can't predict how much of a problem you are going to encounter - it varies.
In my case, Paterson tanks, and mostly AP reels, although I might have had it happen with a Paterson reel as well.. The Paterson core locks, and the reels can rotate freely on it, but the friction between the two seems to cause the reels to rotate with the tank and core, although the inertia of the fluid may affect that - I can't really see, because the lid is on and it is dark in there
And to confirm: it is only a problem for the development stage. I use continuous rotary agitation for all the rest, and the films seem to stay put.

Thanks Matt, you may be right but here's another original thought I have had with reference to Jobo tanks and the Jobo rotary processor. As I said the reel and the tube seems to lock very quickly in either a clock or anti-clockwise rotation but assuming the film or half of the film at least "floats" when immersed and can move independently then as the processor changes direction about every 3 secs then would this tend to reverse the movement of film as well. So in effect it is say 2 steps forward and 2 step back each time the reel completes on cycle of 6 seconds rotation

That might suggest that the film at the end of the total development time stays where it was at the start This may only apply to Jobo tanks being turned in a Jobo processor of course

What might be interesting would be a series of replies from Jobo tanks users who employ a Jobo rotary processor that uses counter rotation to tell us if they notice whether the film creeps forward at all even when it is one film only. Then even better if we have anyone here using the latest processors that rotate I think in one direction only to tell us what they have found

pentaxuser

 

[dynachrome]

I have only tried this with 35mm film. It would not be possible to squeeze 4X5 film into a 35mm reel. I have a number of ways of developing 4X5 film. These include a Yankee cut film tank, a Nikor tank with the special sheet film reel, a red plastic reel which fits into a 3-reel Paterson tank and a plastic reel from somewhere in South America which also fits into a Paterson 3-reel tank.