The lab has always been an interesting place for me. In painting and in the support areas I am continually trying new things. Its called development. Recently I have been working on different grounds. Even the best gesso I can find leaves a surface that is quite absorbent. Since I like to paint wet in wet, I don't particularly like that. Moving the paint around is defeated by such a surface. In addition, the paint is sucked in at varying rates leaving a blotchy surface. This happens during a painting session. If you wait, the condition can be rectified with varnish or, in the case of continuing to paint - oiling in. But waiting causes loss in immediacy.
In an attempt to change all that I did some research. A Lead White ground apparently fixes all that. To avoid the Lead I found a number of alternates and I have tried them on birch board and on canvas. The oil paint sits on top of the canvas making paint manipulation possible. That is you can take your brush and scrape up a mislaid stroke and place it in the right spot.
The painting looks as you painted it like this finished version shown before in a series of steps. Varnish is then for protection. I used no medium for this painting save for the beginning wash.
Bushwork, 12x12 Oil on Gallery Canvas
Here are the trial materials and the results. The highest cost material is first. I have been preparing the canvas to a semi smooth surface. No sanding on the final coat.
Gamblin Oil Painting Ground - beautiful to paint on, slippery - slow dry, thick so one or two coats
Grumbacher MG White - beautiful to paint on, slippery, medium time to dry, thick, one or two coats
Stevenson Oil Ground - nice to paint on, less slippery - slow dry, thin, three or more coats
Benjamin Moore Alkyd outdoor primer - nice to paint on, fairly slippery, quick dry, two or three coats
Zinseel Outdoor Oil Primer (Alkyd) - nice to paint on, quick dry, less slippery, thin, three or more coats
Slow dry means up to a week or more...
Quick dry means less than a day.....
Slippery means the paint can be moved around at will....
If you try a commercial alkyd primer, make sure it is oil based, not shellac. Make sure it is outdoor use.
All of these products are oil based, not acrylic. The bond with oil paint is superior. They contain natural or man made resins so they have varying degrees of odour. I do my canvas and board prep outside in the garage - a problem as we get to the freezing point. Clean up is not as easy as with Gesso. For me the results are far superior. You can buy canvas from people such as Fredrix with lead white prime. Same goes for prepared panels.
Happy painting.