Lessons from John Cosby's Workshop

A small group of about 15 artists gathered on Maui to learn from master plein air artist John Cosby.  Here are some notes and "aaaha!" moments that I hope to incorporate into my future work.

Simplify the Scene

  • The simpler and larger the shapes are in your composition; the stronger your painting will be.    
  •  If an artist can’t break a scene down into 4 or 5 major planes, then they can’t be a successful painter.

Pre-Mix the Value Planes on your Pallet

  • If there is truth in value in the painting, it is easier to embellish and perfect the scene with details to create a successful painting.
  • Only if you have your values correct for the 4 or 5 “plane piles” of color, will you be able to colorize them accurately.

Place the Value Piles onto your Canvas to Create "Planeal Truth"

  • If you are able to paint all four planes of a scene spatially correct; then your painting will be successful. 
    • Vertical Plane – Trees/buildings; usually the darkest color. They do not reflect the sky but do have refracted light from objects that are adjacent to them. Vertical shadows are a lack of light and are darker than cast shadows which reflect the sky back into them.Vertical shadows need to be different and usually are darker than horizontal shadows. 
    •  Diagonal Plane – Hills, reflective sky; usually the 2nd darkest and richest colors. 
    • Flat Plane – Water, tops of things; reflective of sky color.

Colorize the Large Value Shapes to Create Detail


  • Subtle changes to your value piles will create a sophisticated painting.
  • We must decide early on what areas will be warm and which areas will be cool. If we don’t decide this and maintain it thru the process, we will end up with a mushy painting. 
  • Push and Pull color to create perspective.
  • When colorizing your major planes, be sure to keep the value the same so that you maintain the same flat plane. 
  • Keep colors true as you place them on the canvas. Clean brushes often and use different brushes.

Maintain Your Focal Point

    • Determine what your focal point of the painting will be. This will be where the lightest lights and the darkest shadows will be in the closest proximity.
    •  All other elements of the painting should “point” to this focal area.
    • Continue to articulate your focal point thru the entire painting process softening lines and contrasting values to continue to draw energy to your focal point.
    • Be careful not to give color energy in areas that are outside your focal point.
    • Modulate your paint so areas outside your focal point are subdued so that your eye goes along to where you want it to look.
     Beautiful Vistas from the Island of Maui (paintings by John Cosby)

    Day 1: Secret Beach, Kehei

    Day 2: Haleakala Ranch, Makowao
    Day 3: Grandma's Coffee House, Kula

    Day 4: Private Residence, Lahaina

    Day 5: Makena Beach, Kehei

    The artist does not authorize the use or reproduction of any images within this site by any third-party. To receive usage approval, please contact the artist.