This one was surprisingly tricky to paint, due to colour-mixing problems. I have had loads of difficulties mixing a nice, clean, luminous red-orange. But here's the thing: I have found out why. I mixed together combos of every red and yellow I own (rather a lot, I'm afraid) and found the best combo was Rembrandt Transparent Oxide Red and W&N Griffin Alkyd Cad Yellow Light.
The reds -such as Alizarin - also made a nice orange, even if not quite right for this pup - provided I mixed them with the same yellow.
The issue seemed to be the chemical composition of my yellows. The successful one is made of pigments PY74 and PY65 - Arylide Yellows - which mix a reddish yellow. I have other, more expensive, yellow paints made of PY35 which is a Cad Zinc Sulphide sometimes also including Barium Sulfate. This makes a cool or greenish yellow. Hence when added to red you risk getting a brownish result. And not a good brown.
I have learnt the hard way that when my colour mixing goes awry despite trying very hard a solution which is better than banging my head repeatedly on the easel is to go to a site such as this and review the underlying chemical composition of the pigments I am mixing.
Not all yellows are the same.
Christmas Eve tomorrow - yippee! I will post some Christmas Eve paintings for you.