Here's one of Emile Gruppe's original palettes. I conduct a plein air class to Rockport and Gloucester every year (Gunderson's Plein Air Rockport Workshop) and we always stop by Robert Gruppe's studio in Rocky neck to visit- a kind of a plein air artist's pilgramage of sorts. Robert is Emile's son and continues the Gruppe legacy in the studio that was his father's, replete with his and Emile's work. The studio on Rocky Neck has that special ambiance that is an inspiration to the plein air artist and is a must see for any artist visiting the area.. Jennifer Gruppe( Bob's wife) was kind enough to let me photograph Emile's palette which Emile had subsequently turned into a clock. Here one can see how the palette is organized- Cadmium Lemon Yellow at 2:00 and counterclockwise through Cadmium Yellow Deep, Cadmium Orange, Cadmium Red Deep, Rose Madder Deep, Ultramarine Blue, Zinc White ( at 6:00), and Pthalo Blue at 5:00. Also notice that Gruppe inserts Pthalo blue again next to the Cad Lemon Yellow at roughly 1:00 to facilitate the making of cool spring greens and the emulation of a high cool blue greens with a touch of white.
Emile Guppe's palette was idealy chosen to enable the swift color mixing required by his on site plein-aire technique.These colors gave him the highest vibrational chroma avaiable in pigment so as to facilatate his technique of mixing optical grays with complimentaries. Working rather large,( his canvases averqge a standard 18" x 24"), and using a relatively small palette necessitated by his traveling paint box gear, much color mixing was done right on the canvas as he calibrated value and chroma through a approximated cancelling technique. Each color has what is known as an antogonist, i.e., a symmetrical equivalent complimentary across the axis of the color wheel which cancels out the cromatic intensity and/ or value of the color, Gruppe could mentally gauge the antagonist of a chosen color area on his canvas and then"cancel out" the color to the degree of intensity and value he wanted simply by mixing that color into the color already on his canvas. This allowed him to mix "on the canvas" rather than take up valuable real estate on his palette usually reserved for tint mixtures( a color mixed with white) which could easily be contaminated by his powerful dark mixtures.
A list of Gruppé's colors from the book Gruppé on Painting. They are as follows:
Cadmium Lemon Yellow
Cadmium Yellow Deep
Cadmium Orange (added to the palette for convenience)
Cadmium Red Deep
Rose Madder Deep
In The Northlight Book of Acrylic Painting Techniques by Earl Grenville Killeen and Lea Raechel Killeen, Gruppé's palette is described as six colors consisting of a cool and warm of each primary, plus white. Those colors are:
Deep Magenta (cool)
Hansa Yellow (cool)
Ultramarine Blue (cool)
Cadmium Red Light (warm)
Cadmium Yellow Light (warm)
Phtalocyanine Blue (warm)