note on keeping the effect of light

fig.1

 

whether you are drawing or painting keeping the effect of light is one of the most important elements in a piece.   The key to this is to keep a tonal gap between your darkest tone in the light and your lightest tone in the shadow.This gap can be clearly seen it fig.1 where i have isolated the light tones and shadow tones from an oil portrait.  there is a clear gap between the two bands of tone representing the light and shadow.  so it stands to reason that the more tone you use in your lights the darker your shadows need to be in order to maintain the gap.  if there is alot of modeling in the lights this may be necessary but can be over come by the use of temperature instead of value to represent smaller changes.

Toning the canvas and values for white.

Its a good idea to tone the canvas before starting to paint for several reasons.  First of all  it helps you to judge your dark tones as it is hard to see any difference between your darks if they are placed on white.  Secondly it can be use a eiither the color cast of the scene caused by the light or as a complimentary color to vibrate and make the image pop.  Lastly i would recommend toning the canvas in a tone that exactly matches the color of a white object in the light, if there are any spectacular highlights or light sources in the scene.  this makes sure that you always have enough room to push up towards the brighter tones of the highlights.

procedure

over the last few days i have been trying several different painting procedures to see which one i handle the best.   here´s the one i think ill settle for.......

1.  lay in a general tone for the light.  this tone should be the average for the tone in the light (not including spectacular highlights) this is important because you need some wiggle room to go lighter and darker later on without encroaching on the spectacular highlights or getting to close to the shadow tone and destroying the feeling of light.  when we say "light" this includes all halftones.  Generally your tonal difference inside the lights is much higher than the tonal range of the shadows. the light tone must be light, to give the appearance of a lit form.... generally this is lighter than a 5 step on the value scale.

2.  Block in your shadows using as simple shapes as possible.  Don´t forget to squint so you won´t confuse any halftone with shadow.

3.  Add temperature changes to the lights. these can also include some of the slight value changes, but be careful not to make the area "spotty". This is also a good time to put in any turning edges and blend them appropriately. 

4.  Check your edges. You should be trying to get your edges right as soon as you lay down a stroke but its good to have time set aside to check anyway in-case you missed any.

5.  Squint down again and look for all of the darker halftones, lay them in in the correct temperature as you go. make sure they don't approach anything near a shadow tone in value.

6.  Add your highlights being careful with the temperature and blend them appropriately.

7.  now add your dark accents and temperature changes to the shadow.  The value in the shadow never changes (you have the shadow tone and the dark accent no more), all shadow form is turned with temperature.