Teaching Atmospheric Perspective

Did you know that mountains look grayish-purple in the far distance?  Do you know why? 

I always knew to paint the objects in the far distance lighter and more purple/gray, but I don’t know that I ever invested in finding out the why.  For my painting class, I scoured the internet and figured it out.

On a cloudy day, objects far away simply look lighter.  This is because of all of the natural gasses and pollution in the atmosphere. However, on a sunny day with blue skies, the objects far away do indeed have a purplish cast.  This is because the blue sky is actually reflected in the atmosphere and smog.  Who knew?

So as a painter, keep this in mind:  If your landscape is cloudy just make the distance lighter in value, but if there are blue skies in your landscape, make the scenery far away purplish and lighter.

Here’s the tutorials I dug up from the web to give to my students:

Here are the two demos from the project we did in class:

When working with watercolor, there is no white paint.  You simply do not paint where you want something white.  You use the white of the paper.  This image with the mountains lighter in the distance as well as fog rolling through the hills is a wonderful opportunity to figure out how to use the white of your paper.  The trick is a ton of water.  You apply to the paper clean water and then you ever so slightly add some pigment and let it bleed through the area.  If you put paint on one side of the water-soaked area it will be dark on that side, but on the opposite side, the plain water side, it will still be mostly white paper and water.  This creates an ombre effect.  A graduation from dark to light.  There are so many instances to use this in watercolor.  It’s agreat thing to know how to do.

When your out on the highway looking at a large expanse of land, check it out for yourself.  The rule should hold true!