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As I understand it, scale effect is a means of duplicating the effect
of viewing the full-sized subject through the atmosphere which contains
dust and water vapor. The difusing of light by these particles causes
a shift in the gray scale of the subject's colors to lighter and more
gray tones. A 1/48 scale model viewed at a distance of two feet is the
same as viewing the original at 96 feet. In 1/72 it's 144 feet and so
on. Therefore the smaller the scale the greater the effect. Adding
white lightens the color but at the same time subdues it's brightness.
In Belgium and northern France the weather is not often sunny and the
light is very difuse. I've opted for adding white because it just
looks right to me. There's my zwei pfennig's worth.
Cheers!
Greg 'All the world is my friend for I am a brewer.'
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I agee with Greg. People aspiring to become artists (painters of pictures,
that is) are encouraged by their teachers, to observe the modifying effect of
the atmosphere. However the simple addition of white can cause problems.
It is a long time since I have practiced any of this but you cannot simple add
white to some pigments without changing the nature of the colour, eg red becomes
pink. So far as I can remember, the advice given is to chose another pigment
that is naturally lighter than the "body" colour, ie. the natural colour of the
object. If you examine the range of artists colours that are available, you will
find many shades of yellow, red, blue and so on. Most artists do not use the
full range all the time (if at all) but most would chose their palette from the
range depending upon the subject.
The addition of black and white (to make grey) to grey a body colour
is also not always done. Many artists use a complementary colour to grey
another. For example adding green to red pushes the red to grey. The deeper the
original colours, the darker the grey. When I was painting I used a
mixture of burnt umber and prussian blue to create a blackish colour because it
has more "life" than a simple black pigment. A similiar effect can result from
a mixture of alizarin crimson and thalo green.
Likewise mixtures of lighter complementary colours produce lighter greyed tones.
If you want more expert advice I suggest you seek out someone who practices as
a "tonal" painter.
Regards
Paul Butler