Re: pigments for gum and PDN

Uhm...no. Not exactly.

If it filters the exposure at all, it will in terms of neutral density,
not frequency (color). The color is from pigments, whose color is the
result of reflected light, not refracted light as occurs with a BW film
filter. But because it is in solution and is visible, there could
conceivably be a neutral density effect taking place. What would be
interesting is to see just how much of a neutral density effect occurs
and if it varies according to the pigment being used.

Not that I'm set up to do that...8-{

Dennis Moser

Christina Z. Anderson wrote:

> Hi Kees,

{BIG SNIP}

> some effect. But I can only test one variable at once. However, I have
> curved two yellows, an arylide and a semi opaque, and those curves are
> quite similar, which leads me perhaps erroneously to believe still that
> the color is a filter of its own nature, like filters you put on front
> of a camera filter and change the tonal range on BW film.

{BIG SNIP}

> Chris

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