Developing fault with 120 film: what is this mark?

[rexmarriott]

I've twice recently come across this fault that I had not seen before - cloudy blotches, here along the left-hand edge of the negative.

On the two occasions I've seen this I was using different cameras and different films (Ilford HP5 and Kentmere 400), so I'm assuming that the fault lies with my developing process.

Can you help me identify the cause?

 

[Dustin McAmera]

It might be due to foam restricting access of the developer to the film along the edge nearer to the surface in the tank. You could try using a slightly larger volume of solution.

[rexmarriott]

3 hours ago, Dustin McAmera said:

It might be due to foam restricting access of the developer to the film along the edge nearer to the surface in the tank. You could try using a slightly larger volume of solution.

This sounds spot on, Dustin. I will make the necessary adjustments this evening. Many thanks.

[rodeo_joe1]

Could also be air bubbles clinging to the edge of the film. 

Are you using that daft slo-mo figure-of-eight inversion method shown on the Internet? If so, don't! 

I have no idea where that stupid method came from, but it's just plain wrong. 

Simply tip the tank smartly upside down, hold it there for a couple of seconds, then turn it back upright. Repeat that 2 or 3 times, then knock the bottom of the tank on a padded surface to dislodge any air bubbles. (I use a folded towel on my work surface). 

I've used that agitation regimen for 60 years, with thousands of films, and never had a marked film - well, not one that could be attributed to poor agitation anyway. 

WRT sufficient developer in the tank; don't overfill it either. Inversion agitation needs an air space in the tank, because it's air bubbling through the spiral that does the work of mixing stale developer with fresh. And that's why the slo-mo figure-of-eight method is really poor. 

Take note of what Kodak recommend. They should know what they're talking about after all.

Extract from Kodak T-max datasheet - 

Except 7 inversions in 5 seconds is too fast and too many IMHO. Two or three inversions with a count of two in the upside-down position is more like film agitation and less like cocktail-shaking!🙂

Edited February 15, 2023 by rodeo_joe1

[Niels - NHSN]

15 minutes ago, rodeo_joe1 said:

 

Take note of what Kodak recommend. They should know what they're talking about after all.

 

Darkroom life becomes so much easier when you stop listening to amplified internet stupidity and just do what the manufactures recommend.

[rexmarriott]

23 hours ago, rodeo_joe1 said:

Could also be air bubbles clinging to the edge of the film. 

Are you using that daft slo-mo figure-of-eight inversion method shown on the Internet? If so, don't! 

I have no idea where that stupid method came from, but it's just plain wrong. 

Simply tip the tank smartly upside down, hold it there for a couple of seconds, then turn it back upright. Repeat that 2 or 3 times, then knock the bottom of the tank on a padded surface to dislodge any air bubbles. (I use a folded towel on my work surface). 

I've used that agitation regimen for 60 years, with thousands of films, and never had a marked film - well, not one that could be attributed to poor agitation anyway. 

WRT sufficient developer in the tank; don't overfill it either. Inversion agitation needs an air space in the tank, because it's air bubbling through the spiral that does the work of mixing stale developer with fresh. And that's why the slo-mo figure-of-eight method is really poor. 

Take note of what Kodak recommend. They should know what they're talking about after all.

Extract from Kodak T-max datasheet - 

Except 7 inversions in 5 seconds is too fast and too many IMHO. Two or three inversions with a count of two in the upside-down position is more like film agitation and less like cocktail-shaking!🙂

Thank you, Rodeo Joe.

I started processing my own film 8 years ago. I think I got my method from a leaflet that came with a Paterson developing tank, and refined it on the basis of my reading. Am I using the daft figure of 8 method? I hold the tank in both hands, invert it, twisting it at the same time, then right it, twisting again, and then bang the bottom of the tank 3 or 4 times.

I have, from time to time, had problems with 35mm film whereby the sprocket holes show as light ghosts within the frame, along the long side. I read up on this, and found various different suggestions as to the cause. The one that sounded the most plausible was that the agitation was too vigorous and the ghost sprockets were caused by water gushing through the holes. In response to this, I adopted a gentler approach, and have not seen the ghosts again.

All of which is to say that I'm now split as to how vigorous the agitations should be. What do you say?

 

[ed_farmer]

Make sure that you are using a sufficient amount of each liquid in the process.  If it's low fluid level OR bobbles a little more liquid should solve it. 

[rodeo_joe1]

22 hours ago, rexmarriott said:

I hold the tank in both hands, invert it, twisting it at the same time, then right it, twisting again

The twisting motion is totally pointless. It's the tipping upside down that does the job of agitation. 

Save yourself a bit of wrist-ache and just swivel the tank upside down as swiftly and efficiently as possible. That should only need one hand. 

If you're in doubt as to the right amount of developer/fixer to use, it's simple. Pop the spiral into the tank; leaving the lid off, fill it with water until the top of the spiral is just covered by 2 to 3 millimetres (1/8th inch) or so of water, then tip the water out into a measuring cylinder or jug. That's how much to use. You can round it up to the nearest 5 or 10ml to make measuring easier.... but do not fill the tank chock full. Some airspace is essential for good agitation. 

In any case the small extra volume added by the film will increase the level slightly over an empty spiral. 

 

Edited February 17, 2023 by rodeo_joe1

[rodeo_joe1]

WRT sprocket-hole streaming. I can honestly say I have never, ever seen this effect on any film I've developed over many decades, using the method of agitation I described above: Tip the tank upside-down, wait for the air bubbling to stop (2 seconds tops), right the tank and give it a knock on the bench.

Streaming marks usually come from too little, rather than too much agitation. This can be caused by tipping and righting the tank too quickly, and not letting the bubbling airspace do its work of mixing stale and used developer.

Like I said, it's not cocktail shaking, nor a gentle "don't wake the film fairies". It's in between those extremes.

Perhaps it might be instructive to read up on a tried and tested method of large-scale commercial processing agitation called 'Nitrogen-burst'. This was used throughout the film industry before continuous roller-processing became the norm.

Edited February 17, 2023 by rodeo_joe1

[rexmarriott]

6 hours ago, rodeo_joe1 said:

WRT sprocket-hole streaming. I can honestly say I have never, ever seen this effect on any film I've developed over many decades, using the method of agitation I described above: Tip the tank upside-down, wait for the air bubbling to stop (2 seconds tops), right the tank and give it a knock on the bench.

Streaming marks usually come from too little, rather than too much agitation. This can be caused by tipping and righting the tank too quickly, and not letting the bubbling airspace do its work of mixing stale and used developer.

Like I said, it's not cocktail shaking, nor a gentle "don't wake the film fairies". It's in between those extremes.

Perhaps it might be instructive to read up on a tried and tested method of large-scale commercial processing agitation called 'Nitrogen-burst'. This was used throughout the film industry before continuous roller-processing became the norm.

Thank you, Rodeo Joe. Clearly, it was high time I revisited my technique; I'm going to put your advice into practice.

[conrad_hoffman]

I've also used the Kodak method pretty much forever and have never had marks, weirdness, sprocket hole density differences or anything else. I agitate continuously for the first 30 seconds, followed by a sharp rap on the heel of my hand. 5 seconds every 30 seconds after that, though every minute works OK too for longer development times.

[Chris Autio]

I have always given film a water presoak. A professor suggested this after I encountered similar bubble marks. Don’t be surprised or worried by the purplish color that then comes from the soak. Another factor that may or may not allow for such foam markings to occur is how you spool your roll, whether the emulsion side of film is snug against your reel. After a knowledgeable post in this forum said to AVOID this also helped even out my development. 

[rodeo_joe1]

4 hours ago, Chris Autio said:

I have always given film a water presoak.

I don't think a presoak hurts - it can be useful to bring the tank and film up to temperature - but the only circumstance in which it seems essential is when using rotary processing in an oversized tank, where the developer doesn't fully cover the film in the upright position. Otherwise it's totally optional in my experience. 

The only thing that really matters, IMO, is the liquid level in the tank and agitation regimen. Which should be efficient and be kept consistent. Small details, like the number of inversions and the timing between them, don't really make a lot of difference. Because tipping the liquids in and out of the tank prevents split-second timing accuracy anyway, and tanks of different types and sizes vary considerably in how quickly this can be done. 

One afterthought: Use of a surficant like 'Photoflo' in the presoak, or added to the developer, can actually provoke foaming. I'm not a fan of using such stuff until the final wash. 

Edited February 21, 2023 by rodeo_joe1

[Chris Autio]

5 hours ago, rodeo_joe1 said:

Photoflo' in the presoak, or added to the developer, can actually provoke foaming. I'm not a fan of using such stuff until the final wash

One more afterthought, and this came from a colleague in the photo dept and student newspaper, was that remaining photo flo from previous photographers 1) overused Photoflo (all is needed is two - four drops per tank) and 2) did not wash tank thoroughly when done….leading to foamy developer next development.

[glen_h]

Note that Diafine specifically says don't do presoak.

It depends on part A soaking into the emulsion, in the right amount.

 

Other than Diafine, I suppose there is no reason not to do it.

 

I have never had the sprocket hole effect, though much of mine was done with Diafine.

Diafine depends on not too much agitation.  Agitate every minute, through the 3 minute

time in A, and then B.  Most of the development, as I understand it, is in the first

about 10 seconds in part B.  The rest of the time, allows the shadows to develop

just a little more than they would with other developers.