Sorry for the unedited photo.
Here is a paragraph in Carlson's Guide to Landscape Painting by John F. Carlson. He suggested to use Prussian Blue as the primary blue. Did anyone use this as a primary blue ever as Carlson suggested?
I have used both ultramarine and cobalt blue for my outdoor landscape painting. I found that cobalt is a better option rather than ultramarine as it is not overpowering, darks are not unnatural (photographic) and both purples and greens are good.
Yesterday, I used Prussian in a painting just because I ran out of all the blues. I used less, just a tinge of it and mixes were excellent, it can still make reasonably good purples with alizarine and extraordinary greens (at least for blazing summer). Amazing for sky color
. That leads me to these findings:
- It takes less paint; This is where ultramarine fails I guess. Needs practice though in handling this blue
- All the four colors are powerful
- Carlson's finding, which I don't dare to rule out
- Amazing blacks. Cobalt blue fails here