Re: VDB

[Jordan Wosnick <jwosnick@gmail.com>]

On Nov 9, 2007 3:48 PM, Sandy King <sanking@clemson.edu> wrote:

You are smart to work in a humidified environment. The difference in potential Dmax in VDB between working at RH of 35% and RH of 55% is significant, with much advantage to the higher RH. At 35% RH and single coating I am lucky to get a Dmax of 1.30, whereas at 55% Damx is usually 1.45 or higher.

In the winter I run a humidifier in the workroom whenever I plan to print with VDB, kallitype or pt./pd. It is the type that turns off and on to adjust to a certain RH, and I keep it set for 55% RH. Don't just turn it on and start printing when the room RH reaches 55%. You need also to make sure that the paper has had enough time to absorb moisture from the air to reach equilibrium at the same RH.

Sandy -- My system is nowhere near as intricate as yours. I am in an apartment and just use a corner of the kitchen for all my photographic work (no dedicated space for photography, regrettably). I put a pot of water on the stove and keep it at a very low simmer for the duration of the printing session. When the kitchen door is closed, this produces a fairly stable RH of 50% or so. Low-tech, but it does make my VDB results much better. I coat and print in this environment. 

I am looking forward to doing more VDB work after I find a more affordable / more available OHP material -- but that's a topic for another thread.

Jordan


-- 
Jordan Wosnick
jwosnick@gmail.com