Pinholes

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Iwould like to know how to prevent pinholes in large format photography.

-- Art McWhirter (mcwphoto@airmail.net), October 10, 1998

Answers

Use a very, very, very, very weak acid stop bath. To my knowledge this is the primary cause of pinholes, and since I went to a very dilute stop they have not been an issue.

My only concern is that they are actually pin holes and not the garden variety dust spec that all large format users are plagued by. If they are, sorry, you are on your own:)!!

-- Marv Thompson (mthompson@clinton.net), October 10, 1998.


Spot them out on the neg with Kodak Black Liquid Opaque and a 00000 brush.

-- Peter Hughes (leonine@redshift.com), October 10, 1998.

There is no reason to use an acid stop bath for film. Some developers contain sodium carbonate that releases carbon dioxide gas when it comes into contact with acid. Plain water will slow development sufficiently to avoid overdeveloping. Photographers Formulary TF-4 alkaline fixer will not be seriously affected by the small amount of developer carry-over when using a water stop bath. It is an excellent fixer for all film. If your problem is the dreaded dust in the holders, see the September/October issue of View Camera Magazine for an illustraed how-to article on cleaning holders.

-- Michael D Fraser (mdfraser@earthlink.net), October 13, 1998.

A lot of developer manufacturers recommend a plain water rinse instead of a acid stop bath because of the potential for pin holes. Bad enough with LF, a disaster for 35mm.

One remedial solution has been suggest above. You can also etch the final print and remove black spots. Another technique is to use potassium ferrocynide to bleach the spots and then work back down with spotone.

-- Gene Crumpler (nikonguy@emji.net), October 18, 1998.


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