bromide drag? Something else ?? HELP!!

[Peter S]

Guys,

Lately | have been getting these ugly streaks on my negatives between sprocketholes. It has to be bromide drag, I guess. I am using a plastic Paterson tank. Trix and Rodinal 1:50. I already have changed my agitation (more) and it does not really seem to help. It looks as if my first pictures on the role are ok and then towards the end it starts coming up. So the pictures that spool up first are ok, the later ones not.

Could it be I am not spooling up correctly? Towards the end I always have difficulty spooling up, so I guess something is going wrong there.

Fyg I made sure I am not using to much fluids so there is still room for agitation.

Any advice, tricks, maybe stainless is the way to go ?? Maybe stop experimenting with higher dilutions ? Can use all the help I can get. Thanks in advance

Regards

Peter

 

[rover]

Hmmm, I have only had a bromide drag problem once when using Diafine too lazily. I would think the regular agitation used with a normal 1 bath developer would address this. What is your agitation routine?

 

[rover]

Bump, there has to be someone with real darkroom talent hanging around who can offer an opinion so he doesn't have to rely on me. This is too much pressure guys. 😉

 

[Peter S]

I've had it with Tri X at 200; Rodinal 1+50. 1 minute agitation and then 5 agitations (10 secs) every minute. Total time 9.5 minutes

Now it happened with Tri X at 1600; Rodinal 1+50. 1 minute agitation and then 10 secs every 5 minutes. Total time 22.5minutes.

I probably am doing something wrong with the spooling. Does it have to be smooth all the way or is it normal if the last 10 cm of negative are difficult to spool on?

Maybe I do my inversions to gentle, should I be more rough ?

Regards

Clueless

 

[rover]

With Paterson tanks use the stick and rotate the reels back and forth. I don't invert.

I agitate for the first 30 seconds, and then for 10 seconds on the minute after that. So, agitate for 30s, wait 1 minute, agitate 10s, wait 50 sec, agitate 10s,.......

 

[kaiyen]

Your original agitation is absolutely fine. 10s every minute is what I do, and is what A&T recommend. Your second one seems like it's at least possible to cause drag, but I've seen others do way longer in between and be okay.

If you're seeing it only on the outer ends of the reel, then it probably is agitation rather than anything else. It's actually best to do a combination of inversion and rotation. Let's see if I can explain this (that video idea would be helpful here):

right hand on top of tank. left hand on bottom.
invert tank to the right. as you invert. twist your right thumb away from you.
return to vertical as before
invert tank to the right again. as you invert, twist your right thumb towards you.
return to vertical

repeat during your agitation time.

bang tank to dislodge bubbles (no need to be too violent)
twist tank 1/4 turn clockwise (or whatever) so that it'll be starting off at a different point for next set of inversions.

that's what I do. About 5 inversions over 10 seconds is what I do, so I think your agitation speed/violence is about right.

allan

 

[derevaun]

If you can figure out how to load the film with the sky at the bottom of the tank, then (1) you're smarter than I am, and (2) you'll avoid the worst damage from bromide drag when it happens.

It seems that many developers have an active period when a lot of density builds quickly. If that occurs when there's no significant fluid movement, bromide drag is apparently a big danger.

 

[Peter S]

Thanks guys for the advice. The turn and twist will be my new technique. Never thought of using the plastic rod for the twirling, good idea as well.

Also did some searching on APUG and I now think I am not spooling correctly; it should not be difficult to spool; if it is difficult something went wrong and you should start all over again. That at least was the general opinion in a 6 page thread on APUG; a lot of people complained about 36exp film and Paterson reels. I seem not be alone.

One of the problems may be that I cut the film through sprocketholes which can cause jamming; another cause may be that the reel is not clean enough.

Anyway the battle continues, thanks for the listening ear and advice.

Peter

 

[titrisol]

With Rodinal 1+50, agitating every minute I seriously do not think you have bromine drag unless your agitation pattern is not correct. I normally agitate every 2 or 3 minutes with that developer in patterson-like tank by twirling and twisting

Using the "toroidal" movement Allan mentioned you wil get a better agitation patttern that may prevent formation of stagnant developer zones.

To load your spirals, cut the leader of your film and try to get rounded corners, that will make loading a lot easier. If the problem keeps happening "borrow" you mom-in-law toothbrush and clean that reel real well, let it dry thoroughly and try again. I have several reels handy just in case (they are cheap)

 

[titrisol]

PS I think this kind of questions go best in the Darkroom forum....
I normally don;t visit this one due to the large clutter