The tail end of the film coming off of the reel track with rotary processing?

This isn’t a problem I am experiencing. This is just a discussion out of curiosity.

I stumbled upon this YouTube video about the Dev.a rotary processor. From what I can find online, Dev.a requires (or at least highly recommend) you to put their supplied clips on the reels. What I cannot fimd is their reason for doing it.

My hypothesis is that when the reel is rotating in the same direction as the direction of the spiral winding of the film, the “tail” of the film may come off of the track when it hits the solution during the “entry” part of the rotation. (Sorry, I can’t describe it better).

This hypothesis seems to bear out when I look at this Dev.a demo video. It can be seen that they haven't use the film clip in this demo and it shows the tail of the film having come loose from the reel.

But, here is the question and the reason for this post. I have used many different (bi-directional) rotary processors before, and I have never encountered this issue. I have never even thought of this probability. What is your experience?

I have no intention to buy a Dev.a, I am just curious about it.

I have never experienced the problem either nor can I recall ever seeing such a problem being weitten about here on Photrio. However I note from your thread that Dev.a have a video on the problem and as good fortune would have it, make something that is a solution to it

pentaxuser

Tom-Thomas said:

I stumbled upon this YouTube video about the Dev.a rotary processor. From what I can find online, Dev.a requires (or at least highly recommend) you to put their supplied clips on the reels. What I cannot fimd is their reason for doing it.

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This issue applies to 120 Film in a processor with rotating spirals in a horizontal, stationary tank, and at higher speeds (may be over 30 rpm). Phototherm needs such film clips, too. Clearly stated in their instructions.

PittP said:

This issue applies to 120 Film in a processor with rotating spirals in a horizontal, stationary tank, and at higher speeds (may be over 30 rpm). Phototherm needs such film clips, too. Clearly stated in their instructions.

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Thank you for the info. I didn't know about this with Phototherm. When I used a Phototherm way, way back then when I worked in a mini lab, I never did put the clips on — since I didn't even know it's a requirement — but I didn't have any problem with the tail of the film coming off of the reel.

Two questions:
(1) In the Dev.a video, it shows they use the clips n 35mm film also, not just 120 films.
(2) Why does this issue only o stationary tank? What make a stationary tank different from a non-stationary tank, like a Jobo, in this regard? I mean, regardless of the tank being stationary or not, the reels inside rotate just the same, right?

I never had a that problem with 35mm or 120 film in the Jobo processor. I always advance the film as far as I can.