[alt-photo] Re: grainy VDB and cyano

[francis schanberger]

Could be the water supply. Maybe your city or county is adding something to
the water or maybe there has been heavy run off in recent weeks. Try a
gallon of distilled water with the cyanotype processing to see if it makes a
difference. You may have to filter your water.

The VDB chemistry will eventually plate out too much silver in the bottle to
give good DMAX. It does have a shelf life (maybe 3-6 months). I usually go
through a 300 cc of VDB emulsion in six weeks.

VDB, like argyrotype, is highly sensitive to changes in humidity. Sixty to
seventy percent is usually ideal.


-francis



-- 
francis schanberger

www.francisschanberger.com