Weird looking pattern on film, anyone have an an idea?

[tijani]

Hello everyone, I have been developing my own film for more than a year now and I have never seen anything like this on the negatives. I don't think its reticulation but I also don't have any idea what it could be.
The surprising thing is the weird pattern on the film negative shows on some frames within a roll and other frames are completely clear except from the usual dust.

All inputs are appreciated.

 

[nosmok]

I'm assuming this is 35mm negative film, but not sure it really matters. There's what seem to be bubbles on the film surface-- maybe developer is foaming slightly sometimes? Try less vigorous agitation, make sure there's plenty of developer in the tank. It might help to know what developer you use, and if you do multiple rolls. Just spitballing here- even though I'm a Caffenol guy and it does foam during mixing, I've never had that foam make an appearance on my negatives (maybe I'm just lucky).

 

[Daniela]

I've had that happen and, like @nosmok says, it's bubbles.
When it happened to me, it was because the chemistry didn't fully cover the top roll in the tank. In my case, this has to do with how the tank I use is constructed, I have to make sure that the film reels are truly sitting at the bottom of the tank and not on a protruding plastic bit at the bottom. That might be the case for you or you might just need to make sure to use the right amount of chemicals.

 

[koraks]

make sure there's plenty of developer in the tank.

This.
It's indeed foam and it's nearly always related to using insufficient developer.
@tijani, what kind of developing tank do you use and how much liquid did you put in?

 

[250swb]

It could be you didn't have enough developer in the tank, or over vigorous agitation, but you can get foam from not washing wetting agent from the previous session out of your tank or measuring cylinders.

 

[Agulliver]

+1 on the foam/bubbles. Most common causes have been listed, and we've probably all done it at some point. In my early days I was too enthusiastic with the agitation, and in more recent years I've had not quite enough developer to cover a tank full of multiple films. Similar results.

 

[tijani]

This.
It's indeed foam and it's nearly always related to using insufficient developer.
@tijani, what kind of developing tank do you use and how much liquid did you put in?

I use the Paterson tank and the Paterson plastic reels. For this batch, it was done in the 5 tank reel but with just 3 reels loaded.

 

[tijani]

It could be you didn't have enough developer in the tank, or over vigorous agitation, but you can get foam from not washing wetting agent from the previous session out of your tank or measuring cylinders.

I think it’s a mixture of both, got lazy with measuring since I use a 5 reel thank and I usually fill it to the top. This particular batch was 3 reels instead and I must have been my oversight

 

[koraks]

I use the Paterson tank and the Paterson plastic reels. For this batch, it was done in the 5 tank reel but with just 3 reels loaded.

A possible problem with the big Paterson tank and 3 reels is that the reels shift on the center column. The upper reel can thus end up partially submerged or even entirely above the developer level. This can be prevented by always fitting 5 reels on the center column, even if you only load some of them with film.

 

[tijani]

I think too much space inside the tank let the developer solution to foam too much. Please consider the fact that some emulsions (Ilford especially) have a wetting agent embedded in them.

I almost exclusively use Ilford film. What does having a wetting agent embedded in them mean exactly? How does it affect the whole development process? Thanks

 

[Valerie]

Bubbles in the developer. Happens to my students often when the tank's previous user did not wash the photo-flo out properly.

 

[koraks]

I almost exclusively use Ilford film. What does having a wetting agent embedded in them mean exactly? How does it affect the whole development process? Thanks

Some people complain of bubbles/foaming and find it creates visible artefacts on their negatives along the lines of what you've shown.
Personally, I only give my tanks a cursory rinse, I use Adoflo wetting agent in my tanks & reels, and have developed quite a bit of Ilford film and never noticed any problem. On that basis, I'd really suggest first checking the sliding-reels problem I mentioned above.

 

[Ian Grant]

Bubbles in the developer. Happens to my students often when the tank's previous user did not wash the photo-flo out properly.

It's not only the washing though, over time with use there's a slight build up of gelatin where the wet film is in contact with the spirals. It'd near impossible to remove all traces of wetting agent without the occasional more thorough clean. I routinely clean my Paterson spirals, a long soak with a washing or dishwasher capsule in reasonably hot water does the trick, some of my spirals are 50 years old and still work fine.

It means that Ilford uses some kind of surfactant in their emulsions composition, to aid eveness of the developer dispersion on the film in the first seconds you pour the developer solution in the tank.. The surfactant passes in solution during development. In fact you can check it yourself by opening the external flexible lid of the Paterson tank during development.
If you use too large of a tank the free space inside, together with vigorous agitation, will contribute to foam the developer solution even more.

I was going to add that some emulsions contain surfactants, but some developers do as well. So there's a fine balance as these surfactants also build up on spirals.

Ironically I have to add wetting agent to my film developer or I get air-bells as the water where I live has a high mineral content, however as I mix my own developers I add the wetting agent to the concentrate. I did experiment first to see what level stopped the air-bells and the level that caused foaming.

Ian

 

[pentaxuser]

It means that Ilford uses some kind of surfactant in their emulsions composition, to aid eveness of the developer dispersion on the film in the first seconds you pour the developer solution in the tank..

Is this peculiar to Ilford alone? It sounds as if other manufacturers should do this as well or should they? Is this an advantage only when filling the tank but becomes a decided problem if there is some space left in the tank? As a consequence those using a tank that is bigger than needed for the number of reels being processed should consider other makes of film?

pentaxuser

 

[George Collier]

How I try to prevent this -
Never, ever, allow the development tanks or reels to come in contact with photo-flo. (This has been preached by many.) I use a single glass beaker of 500ml for PF only, and rinse last in the sink when finished rinsing every thing else. I dip the film by hand, see-sawing back and forth full length, and hang, one roll at a time. I never use this beaker for anything else, going on 50 years.
I measure how much liquid will fill the tank enough to cover all the reels in the tank, plus a few ml (enough space above chems to allow the chems to move around during agitation), then use that amount no matter how many reels are loaded with film.
No bubble artifacts, ever. I still do get some surge once in a while.

 

[koraks]

@Tsubasa do you get the foam with particular formats of Ilford film? I'm a regular user of 135 HP5+ and I see no foam whatsoever. Never really noticed it on Delta, FP4+, HP5+ 4x5" either; maybe I overlooked it?

 

[pentaxuser]

Thanks Tsubasa. I just wondered if Ilford films exhibited a foaming problem more than other makers' films and if it was bad enough to create much more of a problem for processing than is the case with other films such as Fuji, Foma, Adox and Kodak

My own experience is that even when using a 1 film tank for 1 film and adding a few more ccs of developer I could almost always see bubbles in the top of a Jobo tank when agitating normally but seeing practically no bubbles when using a Durst tank. However my Jobo tank has not given me any more of a problem than my Durst with any film including my "go to" film of HP5+

pentaxuser

 

[Sirius Glass]

Bubbles: Fill the tank more full and after each filling thump the tank on a hard surface several times to break loose the bubbles from the film surface. I thumped my tanks are a thick block of linoleum.

 

[250swb]

Or use the twiddle stick or a swish for agitation and avoid frothing completely.

 

[Laurent]

Happens regularly to me, the cure I found is filling the tank enough so that foam form on top of the réels if it forms.

 

[Ian Grant]

@Tsubasa do you get the foam with particular formats of Ilford film? I'm a regular user of 135 HP5+ and I see no foam whatsoever. Never really noticed it on Delta, FP4+, HP5+ 4x5" either; maybe I overlooked it?

I mainly use Ilford films, Delta 100 & 400, plus HP5 5x4, I've noticed my spent developer is "soapier" after use, but only slightly. When I have long printing sessions my print developer definitely gets soapier, that's with what's left of my Forte Polywarmtone paper.

Something not mentioned is how a tank is agitated, inversion agitation needs to be smooth, over agitation in terms of too vigorous can increase the likely hood of foaming.

Ian

 

[Sirius Glass]

I mainly use Ilford films, Delta 100 & 400, plus HP5 5x4, I've noticed my spent developer is "soapier" after use, but only slightly. When I have long printing sessions my print developer definitely gets soapier, that's with what's left of my Forte Polywarmtone paper.

Something not mentioned is how a tank is agitated, inversion agitation needs to be smooth, over agitation in terms of too vigorous can increase the likely hood of foaming.

Ian

Check the pH, the developer could be coming more basic if it is feeling soapy.

 

[Augustus Caesar]

Always fill the tank almost to the top, regardless of the number of reels being used.

 

[koraks]

Check the pH, the developer could be coming more basic if it is feeling soapy.

Nah. Might as well be becoming more acidic. Or, even more likely: not change at all in terms of pH.
Foaming and pH don't have much to do with each other.
To the extent that running film through a developer will influence the latter's pH, it will be a pH decrease, not an increase.

Always fill the tank almost to the top, regardless of the number of reels being used.

Not necessary. Just ensure the reels are entirely submerged and don't slide on the center column.

Also, people seem to forget that air is lighter than water by a huge margin. Foam floats to the top. It's only a problem if the fluid volume is too low to begin with, or the reels end up sitting partly above the fluid level. It's possible that some tiny bubbles stick to development reels and thereby form a narrow band of low density along the edge of the film (where it's typically not noticeable in the first place). But large areas of foam like this can never be the result of sufficient developer volume combined with foam. It's just physically impossible. If you don't believe me, go sit in a bathtub with lots of nice and fluffy foam, and see if you can get the foam to float under the surface of the water. Take some scuba gear into the tub, if you please. And a rubber duckie.

 

[Mr Flibble]

A possible problem with the big Paterson tank and 3 reels is that the reels shift on the center column. The upper reel can thus end up partially submerged or even entirely above the developer level. This can be prevented by always fitting 5 reels on the center column, even if you only load some of them with film.

Or use the ring clip on the column to hold the reels down, if you have one. Not sure every Paterson tank came with one of those clips.