Some strange low-density spots on my film

[John Wiegerink]

Wait... Problem may come from 20℃ temperature... I will test room temp developing.

I really don't think a few degrees one way or the other would make a difference, but it's worth a try and it cost nothing.

 

[MsLing]

Then it must be a developer "style or type" problem. If things are fine with Rodinal and not with a Vitamin C type developer then there has to be a reason why. I'd start looking at your water quality if you're not using distilled water. Maybe something in your water doesn't like something in your Vitamin C style developer. Maybe Rodinal doesn't care what's in your water? If you use distilled water for all the steps in your developing process I don't know where else to look for the problem. What I'm saying is if you're not using distilled water I'd certainly give that a try since it would be a pretty cheap fix. I wish you luck!

except wash, i use distilled water in all processes

 

[MsLing]

30℃ didn't work. Still spots

 

[MsLing]

I have no idea about what they are and what cause them

 

[MattKing]

That appears to be light fog - it is a faint image, rather than a problem with chemicals.

 

[koraks]

That appears to be light fog - it is a faint image, rather than a problem with chemicals.

I think what we're talking about is not the big artifacts, but the small ones here:

The big ones look like they're caused by how the backlit negative was photographed.

It's really odd, this one. I'm quite sure (but would have to check) that I've developed Fomapan200 4x5" in my own version of instant mytol. Not 100% sure though...What I am certain of is that I've never seen these particular spots on this film. Or any kind of conspicuous defect, really.

@MsLing are you still using a soak prior to development? I'm clutching at straws here, obviously. It's really odd. I wouldn't be surprised if you would hit upon a sheet of film that breaks the pattern of this particular type of developer correlating with this particular defect. I.e. it might be a 'simple' case of one sheet being affected, while the next one isn't, regardless of how the film is developed.

 

[MsLing]

That appears to be light fog - it is a faint image, rather than a problem with chemicals.

May be my phone and hand.

@MsLing are you still using a soak prior to development? I'm clutching at straws here, obviously. It's really odd. I wouldn't be surprised if you would hit upon a sheet of film that breaks the pattern of this particular type of developer correlating with this particular defect. I.e. it might be a 'simple' case of one sheet being affected, while the next one isn't, regardless of how the film is developed.

No, I didn't use, just directly pour developer in. I decide to try FomaRotro320

Quite nice. Rodinal 1+100+2g sodium isoascorbate/L

Same sheet with Rodinal is OK. I am now mixing another version with pure water.

 

[MsLing]

another version with pure water.

slightly better

 

[MsLing]

Surfactants! I think the lack of surfactants cause those spots. Without it, developer cannot opportunely soak emulsion. I added some drops of surfactants into developer and developed another sheet of Retro320, no visible spots and density seems bit lower than without surfactants.

 

[koraks]

Makes good sense; surfactants are often added to developers (e.g. C41 developer usually has surfactants in it) as well as to the film emulsion itself, although in the latter case the rationale might also be coating dynamics.

 

[MsLing]

Obviously cleaner

 

[koraks]

Certainly looks like it, although you may now have something else going on here:

However, maybe this is not in the actual negative and it's just an artifact of photographing the negative. I boosted the contrast in the example above to make it easier to see what I'm referring to.

 

[MsLing]

Certainly looks like it, although you may now have something else going on here:
View attachment 405416
However, maybe this is not in the actual negative and it's just an artifact of photographing the negative. I boosted the contrast in the example above to make it easier to see what I'm referring to.

I check it on negative, that's a shadow of something, film is clean.

 

[koraks]

OK, good. Looks like the surfactant really helps.

 

[MsLing]

Yeah, so I purchase 500ml BASF XP-30. To confirm if antifoam works or not, I also buy some Dow Corning KEF-1410.

 

[retina_restoration]

Why keep exploring this problem if you’ve identified an alternative developer that works well with the Fomapan?? Just use what works and forget the Ascorbate developers.

 

[John Wiegerink]

Why keep exploring this problem if you’ve identified an alternative developer that works well with the Fomapan?? Just use what works and forget the Ascorbate developers.

I scratched my head on that one too Paul?

 

[koraks]

I can relate. You run into this one particular thing that you'd expect should work - and yet, it doesn't. So you keep pushing it until you get it to work, even if there's an alternative. Is it necessarily productive? Perhaps not. Sometimes we learn a thing or two in this way; whether that's worth it, I guess is kind of individual. Either way, I think the option of just sticking to a working alternative has occurred to OP. Apparently they prefer not to. As bystanders, we're then left with the choice to either help them or to step aside.

 

[John Wiegerink]

I can relate. You run into this one particular thing that you'd expect should work - and yet, it doesn't. So you keep pushing it until you get it to work, even if there's an alternative. Is it necessarily productive? Perhaps not. Sometimes we learn a thing or two in this way; whether that's worth it, I guess is kind of individual. Either way, I think the option of just sticking to a working alternative has occurred to OP. Apparently they prefer not to. As bystanders, we're then left with the choice to either help them or to step aside.

I'm guilty of be a little stubborn at times too. Just ask my better half she'll tell you.