Yesterday I said I would write a bit more today about using black. It has caused me loads of problems since I started painting in oils, but I am finally beginning to feel a glimmer of confidence in what I am doing.
Basically, I have tried most of the tube blacks: lamp black, carbon black, ivory black and to be frank am unable to see much difference between them in actual, practical use. Now, I only use them at all for the pupils of my animals' eyes, sometimes for 'eyeliner' (especially cats) and noses (especially dogs) and occasionally, as in today's painting, to get a deep dark background. For all other purposes, I mix my own.
For this dear, little doggy, I took the colours I had used in the American flag (cadmium red medium and Pthalo Blue) and mixed those with the addition of Raw Umber to achieve the darkest darks in the dog's fur.
I have found that my mixed (or chromatic) blacks work best if I use the colours that are otherwise occurring in the painting.
Here are some recipes I have tried and which all work if the context of the painting is suitable (i.e. if one or more of these colours is already being used in the painting)
pthalo blue + alizarin + burnt sienna
pthalo blue + alizarin + burnt umber
pthalo blue + alizarin + raw umber
substituting cadmium red for alizarin produces a warmer feeling black but it can get a bit mucky. For all of them you could use prussian blue instead.
I have also had success with
ultramarine + burnt umber (very dark black)
prussian blue + burnt sienna
pthalo blue + cad red light (a bit too purple for most purposes I find)
pthalo green + alizarin (very good dark in still life especially).
Hope this helps anyone struggling with black! Now I need a similar set of recipes for greens, a colour I find so difficult I try not to use it if I can help it - all tips gratefully received.