Re: Seeking Information on 2 problems with Gum process

["Christina Z. Anderson" <zphoto@montana.net>]

The secret to using cyanotype as an underlayer without its getting too dark 
is to properly develop a curve for it.  It is a very short stop, contrasty 
process and either you underexpose it and get no highlights or you expose it 
correctly and get blocked up shadows.  It has to have a curve that flattens 
the negative considerably. I personally use the PDN system developed by Mark 
Nelson but there are also other methods to do this I'm sure....perhaps Dan 
Burkholder has a cyano curve on his website.

However, another option I have been working with is to print the cyanotype 
layer weakly JUST for lightbox registration purposes, and then using thalo 
blue as my last layer to print in the majority of the blue in the image.  It 
gives it a more "gummy" look that way and more punch. I have also found that 
more gum layers give that nice sheen to the image that I love.
Chris


----- Original Message ----- 
From: "cadunn" <cadunn@vt2000.com>
To: <alt-photo-process-l@usask.ca>
Sent: Wednesday, April 30, 2008 4:50 AM
Subject: Re: Seeking Information on 2 problems with Gum process


> Henry wrote:
> but I found it much better to dilute
> > the coating solution with anything up to six or seven times its own 
> > volume
> > with water. You can hardly see it as you coat it, but the blue is there 
> > OK
> > and you can give it full exposure. Dilute solutions seem to need rather 
> > less
> > exposure than full-strength ones.
>
> lol, Henry -- your msg. came JUST after I had coated the paper and was 
> planning on a much reduced exposure time, which is all at this point in my 
> learning curve that I knew to do --
>
> So, next iteration of cyanotype stage variation belongs to you!
>
> Thanks