The world is full of eggs and egg-shaped things, so I need to know how to paint them. It turned out to be quite difficult. Once I got over the apparent simplicity of an egg, I realised that they are full of shifts in hue, value changes, and variations in colour saturation. To add to the confusion, all these shifting variables change according to what’s around them. For instance, the high chroma oranginess of the egg only appeared when the background darkened and turned towards a blue-green-grey.
My aim was not to create a good composition or even an attractive picture, but to paint what I saw as accurately as possible. I used the Holbein Duo Aqua oils with a little of Gamblin’s Galkyd Slow Dry medium as an experiment in smoothing out the brush strokes. Sometimes the light rakes against the tiny ridges made by brush strokes in paint straight out of the tube causing patches of glare, which can make it hard to judge the colour. The medium evens out the surface and also makes the paint thinner and easier to blend. (Oil paint mediums are a rabbit hole of conflicting advice, I found out.)
The set-up was the egg placed on a slightly faded cloth-bound book with the light coming mainly from a desk lamp fitted with a daylight bulb placed a few inches away. I surrounded the back and sides with some black-covered sketchbooks to lower the reflected light and increase the contrast between the light and shadow.
There appeared to be a halo of washed out colour around the highlight, followed by increased saturation moving through the halftones into the shadows, but some areas of the darker halftones also seemed to have low chroma. It really was a case of careful observation then trial and error. Sometimes I would hold the mixed paint on my brush next to the part of the scene I was painting to see how they compared. Mark Carder has invented a colour checker for doing just this but it requires close attention to the lighting to use it accurately, so somehow I need to develop an intuitive way to get to the right mix of paint. This will probably involve painting lots of eggs.