Fabriano 5 works well as do the Artisticos if they are given a good sizing
first.
>>After 4 exposures I noticed that the gum/pigment seemed to be sloughing
off
>>in various areas of the image giving a slightly mottled look.
>I have seen it mentioned elsewhere on the list to re-size with gelatin
after each coating. <
Resizing works well but the colour sloughing off seems to be more a
question of too much pigment not allowing the light to do its work.
>I don't currently do this but not a bad idea, I sure
someone else will post more details on this approach. I have found that
this problem seems more related to the paper you use than the sizing. I
use two gelatin baths, with formalin added to the second bath. I find
that this can hold up for 6-8 coatings on the saunders papers, and a
little more with Bockingford<
Reccently I tried a three coat gum with Bockingford with no size, a
hardened size, a dichromated and exposed size, and between coats size. No
discernible difference !
> This stain problem has in my experience been primarily occurring
with either Winsor Blue or Cadmium Yellow.<
It is a good idea to get W & N booklet on the qualities of water-colour
which will trell you colours that styain and those that flake in
conjunction with other colours. One staining colour is Hooker's Green. I
assume that this was developed by Mr Hooker.
>
>>did not print on it until 2 days later. Should I add more chrome alum to
>>the gelatine
It is proabably better to do a test strip to see what effect exposures have
on the colour. I keep the chrome alum now for the first coat of gelatine
in preparing oil printing paper.
>Perhaps other people on the list may confirm this but apart from the
prepartion of the paper, and the type you use, the concentration of gum
pigment, and the length of exposure will all have an impact on the things
you mention. :<
Remember the first principle that if the pigment is too thick the light
will not be able to get at the chrome salt to effect the chemical reaction.
Moral: use small amounts of strong pigments.
Terry King