What's that stuff in my negatives?greenspun.com : LUSENET : Large format photography : One Thread
I am a survivor from a long session in my darkroom and although it has been a productive one in some new 4x5 negatives i have found stains i have never seen before.
They are round and if i enlarge the 4x5 sheet to 16x20 the dimensions of their diameter is about 1/4 iinch, but i have found smaller ones.
Is there a dark presence in my darkroom? Uneven development? contamination? I said they are stains but to be more precise they are just circles of a lighter shade..... Has anybody made the same mistake i am doing ?
-- domenico (email@example.com), May 15, 2002
Air bubbles; use a presoak..
-- Per Volquartz (firstname.lastname@example.org), May 15, 2002.
Probably air bubbles.
-- paul owen (email@example.com), May 16, 2002.
They are air bubbles. Soak for 1-2 min. in water w/ 1 drop (no more) of Foto-Flo. Add 1 drop of Foto-flo to the developer also. You'll never see a bubble again.
-- Steve Feldman (firstname.lastname@example.org), May 16, 2002.
The answer Kodak gives to the air bubble problem is to tap the tank sharply on the counter to remove the airbubbles when you begin developing. This does not always work. The answer is to fill your developing tank with water of the same temperature of the developer you are going to use. I always use 68 F developer so I soak the film in 68 F water and place the tank in a dishpan of water at the same temperature. Let everything soak for 2 minutes. This is not critical since I see no reason why the film can't soak a little longer. This has totally eliminated air bubbles for me and everyone I have work with who has had the problem. I feel it is also a working procedure which contributes to very even and consistant developement of the negatives from batch to batch.
-- Thomas Born (email@example.com), May 17, 2002.