Weird blobs on film...

[ekimeno]

Can anyone help me pinpoint the source of this strange artifact... Discovered this on a couple of images yesterday while scanning a roll of 120 and thought it might have been drying marks, so just cloned them out and did an extra thorough job cleaning today's negs, but the problem has re-appeared.

Light leak?

 

[roofowler]

I had something similar and thought it was my camera (RB67) but in the end I decided the problem was in the processing, I was using a paterson hand tank and I think it was bubbles, maybe I didn't put quite enough developer in to entirely cover the film becuase when I processed the film in a deep tank, the problem went away.

 

[ekimeno]

Bubbles makes sense, though I'm using a 3 x 120 film Paterson tank, always overfill by 100ml-200ml and do the old tapping of the tank on the sink after each inversion.

Then again, this is the first time I've been trying 1:100 concentrate (Rodinal), and doing a method which involves deving for 18 minutes, with one inversion every 3 minutes (once a minute for the first 3 minutes). 3 minutes of standing would surely be enough for bubbles to leave their mark.... :shrug:

 

[Terrywoodenpic]

Almost certainly Bubbles .
Your agitation is suspect... I would Invert constantly for the first 30 seconds with bumps on the table between... Then do as you were doing, with a bump after each inversion.

This starts the development with a fully saturated film and remove bubbles.

 

[ekimeno]

Sweet - route of the problem is the initial agitation then... Your suggestion is how I normally develop B&W with constant inversions for the first 30 seconds, but this method was suggested somewhere else on the web and seems to work OK if it weren't for the bubbles...

Thanks for the tips

 

[Ambermile]

Look like sheep to me :shrug: