Streaking from sprocket holes during long dev times

[EASmithV]

I've been using primarily Rodinal Stand Dev as my BW Go-To developer, and i've been having a little bit of issues when using it to push film.

For instance, my latest few rolls of TMY-2 exposed at 1600 and developed for 3 hours 10 minutes are exposed and developed perfectly, save for the strange streaks caused by the sprocket holes on either side of the film. It is perfectly even, and doesn't seem to come through much in what I've scanned so far, but it is bothering me. I don't get this issue with Medium Format.

 

[Newt_on_Swings]

I have been getting them too and its been a bit annoying on pushes. Similar setup, using Tmax 400 (TMY older version) 1:100 rodinal semi stand for 1-1.5hrs. They are more noticeable on the edges of the film, and some have even gone into the image area.

I have guessed that the cause is surging of the developer through the holes during agitation, and I have reduced my initial agitation time, as well only doing 1-2 slow inversions at the halfway mark.

 

[MattKing]

Isn't that a problem with bromide drag?

 

[Ian C]

Streaking about the sprocket holes of 35mm films is bromide drag. It’s caused by not agitating frequently enough. It can happen with any size film. The sprocket holes in 35mm (and other perforated-edge films) tend to generate flow streaks about the holes making the streaks more visually obvious than on non-perforated films.

If you practice the Kodak or Ilford agitation schedules with standard developers like D76, HC-110, T-Max, T-Max RS, Ilford ID-11, Ilfosol, etc. the bromide smears don’t form.

I don’t know what agitation schedule is required to prevent bromide smears in film developed for 190 minutes in dilute Rodinal. Obviously, it’s receiving too little agitation. Properly agitated, the bromide smears won’t form.

 

[David Lyga]

You have to understand that when you cram so much film onto a reel and each layer is only a few mm distant from the next, the flow is compromised. The sprocket hole areas allow a free flow of developer and with the areas for which there are no sprocket holes, the flow is somewhat restricted. Solution?

I agitate continuously, gently, and leave no area of the film untouched. It's somewhat like washing clothes on the gentle cycle. I never have that problem. It might be a bit of a hassle to keep moving all the time but isn't it easier that dealing with the aftermath? Bromide drag can leave streaks down the film, in the direction of gravity. - David Lyga

 

[Oren Grad]

It might be a bit of a hassle to keep moving all the time but isn't it easier that dealing with the aftermath?

By definition, stand development doesn't allow continuous agitation. If you want the supposed benefits of compensating development, the film has to sit undisturbed for substantial periods.

I gave up on stand development myself - I didn't like the results any better than what I get from normal development, and so it wasn't worth the trouble for me to figure out how to squelch the bromide drag problems I was having. But if you want to do it, you'll just have to tinker with agitation until you find a pattern that avoids bromide drag without being so vigorous as to negate the stand effects.