>>Sure enough Pete but people need to be warned that testing can become such
an obsession that it can become the end in itself.<<
I agree but this is not often the case, for most people and certainly my
students testing is boring and best avoided, however if full technical
control is required testing at some point will be found to be is essential,
as Kodak or Windsor and Newton may not have done the relevant tests.
>>I like to warn students to beware of the overcomplicated and the
irrelevant. Understand the principles and keep it simple !<<
So do I !
>>On another tack, I also found it surprising that you think in terms of
percentages of colour in a mix and that you found that more colour was
likely to lead to less staining.<<
Where did I say this ? I must apologise if I have mislead you or members of
What I did say was -: Phalo blue is a colour which can stain easily if you
overload the gum mix it has a high tincture strength, I use it at 1+ 8 in
my tempera print work
and do not have any problems as long as I do not go below that dilution.
This is not a percentage but a parts by volume measurement for instance I
take one (1) part of Liquitex phalo blue acrylic liquid colour and mix into
eight (8) parts of sensitised egg, reducing this dilution would in effect
increase the percentage of colour to the detriment of the mixture. I know
this to be a fact as I have tested it :-)