Interested in tonal and grisaille painting?
I've collected some free online videos below to provide context and an introduction to various approaches (or reasons to use) grisaille and monochrome or tonal painting. These steps are all about the form. This is the reason students (like those at Agile Arts Atelier) begin with casts and white objects.
Jon deMartin's introduction provides useful context.
This video of Mandy Boursicot moves rapidly but is a great overview in only 10 minutes.
Why use Grisaille or other forms of underpainting?
This is a natural question given that many talented painters today don't use this method while others rely on it to create beautiful 3 dimensional looking work (particularly for portraits and figures). When pigments were expensive and time consuming (prior to pre-mixed tube paints), grisaille provided a cost effective way to establish the volume of forms, accurate drawing and composition before using that precious color. Today, that remains a useful step to insure the same benefits regardless of the cost of pigment. But, it also serves another important purpose as light passing through some upper layers of pigment (particularly with a glaze) reflects off the opaque white areas or is absorbed into the dark areas. In the Agile Arts Atelier we use it as a teaching tool to transition students from drawing through monochrome painting into color. Even if you are an alla prima painter, there is no disadvantage of learning and practicing the various approaches to underpainting and tonal painting because it will help you understand and leverage the grey tone on your support while painting alla prima.
Here's a video introduction to the history dead layer of painting.(Please don't use this narrator's pronunciations of words like grisaille or names like Titian, I think he must have been reading from a script.) They've kindly put their advertisement at 18:40 near the end of the video so you can stop watching at that point if you aren't interested in the ads.
To students who are learning here at Agile Arts Atelier and comparing methods you see above: I've never found ANY video fully illustrating ( step by step ) the exact way I was taught grisaille. But, all of the approaches make sense once you learn some key components of form painting and why to use them. If you are studying it here it's still useful to see different approaches. Hopefully these videos will be an interesting survey.
Finally, in a related topic, here is another video introduction to glazing.