Overdeveloped Edges

[morback]

I may have found a (surprising) answer while doing a search here, but I will ask again:

Symptoms:
Film edges come out overdeveloped.

Gear:
Metal tank and reels.
Rodinal / R09 developer.

Films affected:
Acros (35 & 120)
Plus-X (120)
FP4 (120)


Because it affects multiple formats of film and multiple cameras, the issue has to do be with the operator / chemicals / tanks.

I was using the bottom of a 3 year old Rodinal, but even after cracking a new one open, same problems.

After some research it seemed that the problem might have been strong agitation, so I reduced my inversion length from 2 seconds to 8 (or 1 inversion every second instead of 3-4 every minute), but I got the same effect, though somewhat diluted, broader.

I don't remember having had this issue in the past. So, could I be not agitating "strongly" enough??

 

[x-ray]

You're agitating too strong. Try to change the pattery that you invert the tank each cycle. Make your agitation more random in pattern and be gentle. Add a little twist to the wrist or do something so you don't setup a turbulent flow of chemicals.

 

[x-ray]

Try using a different method if agitation. Leave the tank sitting flat on its bottom and rotate the tank clockwise sharply and then counterclockwise. Don't raise the tank and invert it.

I do this and alternate the next cycle by just tipping the tank and twisting my wrist. I don't actually invert the tank. I found the reel sliding back and forth sets up turbulence around the edges. Gentle random cycles works for me. I've run many thousand rolls doing this and not had edge problems.

 

[Dante_Stella]

To back up a step from the agitation, are these negatives adequately exposed and developed? I don't know what to make of them from the scans, but I have observed that underexposed and underdeveloped shots are much more vulnerable to edge-of-frame effects, streaking, and other irregularities.

Dante

 

[Dan Daniel]

If you are inverting, is there air in the tank? I needed to reduce the amount of developer to leave enough air for the developer to actually be able to flow and move. I put an empty reel in the tank to check how much liquid is needed to cover the reel.

I do 'hard but slow'?? inversions. I flip the tank quickly, but pause after each flip for a couple of seconds to let the developer catch up and flow. With an air space in the tank the fluid has the room to actually move, not just pass wave energy back and forth. If I get impatient in the developing and do my flips too quickly, I see a slightly overdeveloped edge.

 

[Ronald M]

Edges are probably not overdeveloped, the center is underdeveloped providing you are somewhat close to the manufactures time/temp and not following Massive development chart.

At any rate, the difference is due to poor agitation because the edges have the developing byproducts removed and replaced with fresh developer and the center does not.

There is a ton of misinformation on the internet by self described experts and one of them is nice gentle agitation. Presoak is another.

One way to get the results you have is swirl or rotation. That is ineffective.
You can rotate, but the film must the raised and lowered also.

Plastic tanks need the twirl stick only on first agitation. After that invert. Read the instructions. Unfortunately used tanks come without. It is not a take your choice.

Stainless tanks, invert 5 time in 5 seconds. or use a two reel tank with film on the bottom reel, top empty and enough developer to cover the bottom. Invert twice and the film comes out of the developer completely/

Lastly, agitate in fix vigorously as it needs more than film or at least as much. Under fix agitation will dealve a dark center strip.

 

[julio1fer]

This is not edge problems, it is uneven agitation. In my experience (about 45 years developing my own B&W) these uneven development problems come from too scarce agitation rather than too much.

IMHO, there is a lot of trash in the Internet about "gentle agitation". It is all about having the chemicals distrbute evenly along the film, so you must agitate well! Remember that manufacturers give times for continuous agitation, which is what happens in machine development anyway. Agitation is not bad, is something you need to have.

A couple of inversions every minute work well, do not be shy about moving those liquids inside the tank, they need it!

 

[morback]

Solution:

Stronger agitation.

thanks!

 

[Photo_Smith]

It could be agitation, but my guess is that when loaded in the spiral the centre of the film is curved towards the film underneath, the edges being held near the spiral edges have a greater distance – the centre could even touch the film underneath.
When you agitate the centre of the film that is stuck to the film below is starved of fresh developer while the solution rushes at the edges giving good agitation where the distance is larger.

Difficult to explain, easier to see when you take it from the wash and normally it happens near the end or last frames more...
What type of spirals do you use?