Rotary processing and surge marks/bromide drag?

[Sirius Glass]

Since I switched to rotary development I have not had streaking or uneven skies.

 

[pentaxuser]

logan I found a second set of rollers tonight and tried both sets next to each other. You are right it is impossible to use both sets with a 1510 tank as it just isn't long enough but it works fine with a 1520. I filled a 1520 with 240ml of water and this made the tank even more stable. With one hand's thumb and index finger holding both sets of rollers together so the spinning didn't cause them to move apart and rotating the tank with the other hand I found it relatively easy to spin the tank in both directions. If the 2 sets of rollers were fixed down then you even have a spare hand for changeover every couple of minutes.

It means a reasonable saving in chemicals. I know you said you might give it a try and my experience suggests that you will find it works OK

pentaxuser

 

[logan2z]

Well, I just had a look at my latest roll and there's a few frames that have that same unevenness along the top of the frame in landscape orientation.

I shot with a different camera/lens this time so it's not an in-camera problem. I used the small Jobo 1520 tank with 250ml of chemistry to ensure that I'm over the minimum for rotary processing (240ml according to Jobo). This time around, film was Ilford FP4+ and the developer was Rodinal 1:50.

All of the other frames look good - oh, except for the very last one again which shows some vertical streaks. I'm really starting to wonder if these issues are related to photoflo/the drying step as - again - the streaked frame was at the very bottom of the strip as it hung vertically to dry. And this roll and the last roll are the only two that I decided to finger squeegee after the final rinse, and these are the only two rolls on which I've ever seen this edge effect. Could Photoflo possibly be pooling around some of the sprocket holes and producing this? Or am I grasping at straws here?

Just for kicks, here is the scan of one of the frames showing the unevenness along the top edge:

And a photo of two adjacent affected negatives, tweaked to show the issue more clearly. There were many other photos in landscape orientation that did not show this issue.

In an effort to track this issue down, I might do the final rinse of my next roll with distilled water only and skip the Photoflo entirely. I might end up with a ton of drying marks but I'm curious to see if these edge anomalies and the streaking at the bottom of the film strip go away.

 

[Sirius Glass]

I use 500ml for developing with the 1500 tanks and I have no problems with surge marks or drag marks. I either reuse the chemicals the appropriate number of times adjusting for number of rolls processed or in the replenished model. The larger volume helps eliminate the surge and drag problems.

 

[john_s]

. I used the small Jobo 1520 tank with 250ml of chemistry to ensure that I'm over the minimum for rotary processing (240ml according to Jobo). This time around, film was Ilford FP4+ and the developer was Rodinal 1:50.

To me, the unevenness still looks more like development than drying artifacts. Using 10mL over the minimum is insignificant. Sirius Glass has suggested using 500mL and I think that's worth a try.

I can understand that there are reasons to use minimal chemistry especially to not overload a motor driven rotary processor, economy, reducing pollution to name a few. But we go to a lot of trouble to take and develop photos and it's a shame to spoil the result for the sake of minimizing developer.

The amount of liquid in a tank, whether inversion or rotary, makes a difference to the amount of turbulence (which is equivalent to a different amount of agitation at different points on the film).

 

[logan2z]

I use 500ml for developing with the 1500 tanks and I have no problems with surge marks or drag marks. I either reuse the chemicals the appropriate number of times adjusting for number of rolls processed or in the replenished model. The larger volume helps eliminate the surge and drag problems.

Are you referring to rotary or inversion processing? I was using 500ml when doing inversion processing in the 1520 tank but reduced it to 250ml for rotary processing based on Jobo's guidance.

I thought one of the advantages of rotary processing was reduced chemistry usage.

 

[logan2z]

To me, the unevenness still looks more like development than drying artifacts. Using 10mL over the minimum is insignificant. Sirius Glass has suggested using 500mL and I think that's worth a try.

I can understand that there are reasons to use minimal chemistry especially to not overload a motor driven rotary processor, economy, reducing pollution to name a few. But we go to a lot of trouble to take and develop photos and it's a shame to spoil the result for the sake of minimizing developer.

The amount of liquid in a tank, whether inversion or rotary, makes a difference to the amount of turbulence (which is equivalent to a different amount of agitation at different points on the film).

Agreed, I don't really care about minimizing the use of chemistry, I was just following what Jobo recommended. I'll use 500ml for the next roll and see how that goes.

Are we basically saying that one should use the same amount of chemistry regardless of whether rotary or inversion processing is being used? If not, how does one know how much to use for rotary processing if Jobo's guidance can't be relied on?

 

[MattKing]

Jobo's guidance - in fact every tank manufacturer's guidance - is usually about the minimum amount of usable chemicals.
There is one qualification to that - concerns about wear on motors tend to result in recommendations about the maximum amount to be used.
If you use replenished chemicals, the minimum amounts cease becoming an advantage.
I use inversion agitation, not rotary agitation for all but the first 30 seconds of development. In my one litre Paterson tanks I always use the full one litre of replenished developer, no matter how many rolls I'm developing.
The rest of the processing steps are agitated using a rotary agitator. For them, I use 650 ml, because that ensures full coverage.

 

[Steven Lee]

Are we basically saying that one should use the same amount of chemistry regardless of whether rotary or inversion processing is being used? If not, how does one know how much to use for rotary processing if Jobo's guidance can't be relied on?

I think people are just bored and posting meaningless small talk. You can use the search feature to find several old threads on this topic. The only usable advice I ever found was to experimentally find the rotation speed which eliminates these marks. There simply aren't any other variables to tweak.

My personal conclusion is that rotary is challenging when done manually. I used to get these marks too and I rotated with my fingers by floating a tank in a water bath instead of rollers. No matter how steady and consistent I tried to be, I'd still get those marks every once in a while. It all stopped after I moved on to a motorized processor.

 

[logan2z]

I think people are just bored and posting meaningless small talk. You can use the search feature to find several old threads on this topic. The only usable advice I ever found was to experimentally find the rotation speed which eliminates these marks. There simply aren't any other variables to tweak.

My personal conclusion is that rotary is challenging when done manually. I used to get these marks too and I rotated with my fingers by floating a tank in a water bath instead of rollers. No matter how steady and consistent I tried to be, I'd still get those marks every once in a while. It all stopped after I moved on to a motorized processor.

Thanks. That very well could be it, although I've developed several rolls using manual rotation and the last two rolls are the only ones that exhibited this particular problem. Maybe I've just been fortunate that this didn't happen before now.

 

[Don_ih]

5 ml of Rodinal is the bare minimum to develop a roll of film. If using a smaller volume of chemistry, choose to have it more concentrated - such as 1:25.
PhotoFlo is likely not a cause. Developer beading in the reel track while rotated out of the developer, if the rotation is too slow, could cause the problem. Rotate faster?

 

[pentaxuser]

Agreed, I don't really care about minimizing the use of chemistry, I was just following what Jobo recommended. I'll use 500ml for the next roll and see how that goes.

Are we basically saying that one should use the same amount of chemistry regardless of whether rotary or inversion processing is being used? If not, how does one know how much to use for rotary processing if Jobo's guidance can't be relied on?

A good question and one that I have yet to see answered in a way that unequivocally covers the source of your problem and produces an answer that more liquid than the maker of the tank stipulates will solve the problem

If it seems that the solution is to use more than 240ml then by how much? You already use 10ml more so is it 20,30, 40, or in one case double at 500ml?

If 500ml for rotary processing is required and this is double what Jobo stipulates then how much more is needed for inversion - 1000ml?

Can I ask if those others using more than the Jobo amounts did so from the start or because they found the same level of streaks in their negatives at 120 ml in a 1510 and 240 ml in a 1520?

You said that in the roll you had many shots with no streaks so the key question as I see it is: What was it that gave streaks with 250 ml on some negs and not on others on the same roll

Can those advocating more developer( unspecified amounts) ) or in one case double the amount give an answer that covers why this is?

I have only ever used 120ml in a Jobo for C41(35mm only) and have never had your issue. So was I just very lucky(seems doubtful), never shot skies ( not the case) or does this kind of streaks happen only in b&w so my experience with C41 is irrelevant? Oh and it didn't happen with b&w chromogenic film ( Ilford XP2) but I assume this is classified as C41

pentaxuser

 

[logan2z]

A good question and one that I have yet to see answered in a way that unequivocally covers the source of your problem and produces an answer that more liquid than the maker of the tank stipulates will solve the problem

If it seems that the solution is to use more than 240ml then by how much? You already use 10ml more so is it 20,30, 40, or in one case double at 500ml?

If 500ml for rotary processing is required and this is double what Jobo stipulates then how much more is needed for inversion - 1000ml?

Can I ask if those others using more than the Jobo amounts did so from the start or because they found the same level of streaks in their negatives at 120 ml in a 1510 and 240 ml in a 1520?

You said that in the roll you had many shots with no streaks so the key question as I see it is: What was it that gave streaks with 250 ml on some negs and not on others on the same roll

Can those advocating more developer( unspecified amounts) ) or in one case double the amount give an answer that covers why this is?

I have only ever used 120ml in a Jobo for C41(35mm only) and have never had your issue. So was I just very lucky(seems doubtful), never shot skies ( not the case) or does this kind of streaks happen only in b&w so my experience with C41 is irrelevant? Oh and it didn't happen with b&w chromogenic film ( Ilford XP2) but I assume this is classified as C41

pentaxuser

Hoping someone else answers because I'm clearly out of ideas

Maybe it's time to go back to inversion if rotary processing without a machine is problematic, although it's strange that my first several rolls developed using the Roller did not have this edge-related issue. A last resort is to throw in the towel and start using a lab again, although they weren't incredibly reliable either.

 

[Sirius Glass]

Are you referring to rotary or inversion processing? I was using 500ml when doing inversion processing in the 1520 tank but reduced it to 250ml for rotary processing based on Jobo's guidance.

I thought one of the advantages of rotary processing was reduced chemistry usage.

Rotary, aka Jobo CPP2+.

 

[Sirius Glass]

Hoping someone else answers because I'm clearly out of ideas

Maybe it's time to go back to inversion if rotary processing without a machine is problematic, although it's strange that my first several rolls developed using the Roller did not have this edge-related issue. A last resort is to throw in the towel and start using a lab again, although they weren't incredibly reliable either.

OR buy the Jobo processor which will last for decades and more than pay for itself in consistently great film development and longevity.

 

[logan2z]

OR buy the Jobo processor which will last for decades and more than pay for itself in consistently great film development and longevity.

I'd love one but, unfortunately I don't have the space for a processor at the moment.

 

[Sirius Glass]

I'd love one but, unfortunately I don't have the space for a processor at the moment.

First buy a left handed house or room stretcher. ...

 

[pentaxuser]

Well we have been given one more explanation, namely Steven's that might be the solution, namely a mechanised rotary processing procedure AKA a Jobo processor. This, it is postulated, works because it maintains a steady and fairly high speed compared to hand rolling which might be slower even at the start and more likely to be slower over the kind of time required for a b&w film

Certainly when I tried it by hand with 2 rollers I felt I had difficulty achieving the speed that the Jobo achieves for even a short time and then allowing for the need to change rotation about every third turn ( but is that really required?- I don't know) I felt that it was probably impossible

What may be the case is that if you cannot replicate the mechanised rotation speed and direction change of the Jobo and this is the required speed or close to the required speed then assuming that this is the solution it may be that a mechanised Jobo is the only way to ensure 100% success

However( there is always one of those, isn't there ? ) I cannot help wonder why a very vigorous inversion agitation on a constant basis cannot achieve the same effect as continuous mechanised rotation

After all the film doesn't know that the liquid charging round it in the absolute darkness is in fact not rotating or does it After all provided the temperature is correct is anyone saying that inversion rotation is the only way to ensure perfect C41 negs?

pentaxuser

 

[MattKing]

I use a Beseler Rotary agitator with Paterson tanks.
Here is a photo with another alternative - it shows a way to use steel reel tanks, as long as you don't mind the clatter.

Here is an internet pic of the agitator:

It is slightly smaller than the light source on logan2z's enlarger

 

[Sirius Glass]

I use a Beseler Rotary agitator with Paterson tanks.
Here is a photo with another alternative - it shows a way to use steel reel tanks, as long as you don't mind the clatter.
View attachment 321857

Here is an internet pic of the agitator:
View attachment 321858
It is slightly smaller than the light source on logan2z's enlarger

But neither one has the temperature controls of the Jobo processors.

 

[MattKing]

But neither one has the temperature controls of the Jobo processors.

I always process black and white film at the ambient room temperature, adjusting development time appropriately.

 

[FotoD]

Maybe it's time to go back to inversion if rotary processing without a machine is problematic

That's what I did. Rotary 35mm and 120 film always gave some sort of unevenness, whether in a Jobo or on a motor base. Inversion on the other hand gave clean negs.

 

[Sirius Glass]

I always process black and white film at the ambient room temperature, adjusting development time appropriately.

So do I.

 

[Sirius Glass]

That's what I did. Rotary 35mm and 120 film always gave some sort of unevenness, whether in a Jobo or on a motor base. Inversion on the other hand gave clean negs.

Whatever floats your boat. Jobo processor owners will not agree.

 

[FotoD]

Jobo processor owners will not agree.

I'm one of them.

The Jobo worked great for sheet film. But under certain conditions rotation isn't ideal. I could never figure out exactly why it didn't work for 35mm and 120.