Good morning Joseph. Thanks for your comments. Let's me know I am on the right track. Yes, without the challenge it becomes boring and not really worth the effort. But the learning is worth every effort. I have painted the way you say you do, a lot. It is a pleasant creative experience, enjoyable actually. When studying the pictures I took of the canyon it occurred to me that I could not paint what I wanted to present without doing the study drawings first. There are simply to many shapes, shadows and forms for me to keep track of while doing the holistic experience of creating the finished painting all at once. I have to break it down like a shotgun into pieces and reassemble them to make it work.
I know that study drawings are and were used by artists throughout time. When I was in school I thought they were a waste of time unless my class grade depended upon them. You know how when you were 20 to 30 something you knew everything about everything that was important? Well, not so much these days. Doing the study drawings has brought a new awareness about how to manifest that final product. I can better see and map the shading levels I want on the shapes. It is helpful to use the lines and shading with directional purpose that will remind me how to apply the paint and what knife strokes I will need to present the forms. That kind of thing.
As to knife versus brush with the knife being easier to use than the brush, I have not found that to be true. Most of the time with the brush, when you make a mistake you can paint over, wipe it clean and do it again, or just stubble it. True, it saves time cleaning brushes but on the other hand you have to inspect the cleanliness of the knife each time before you load it with paint. Nothing like a little hard dot size chunk of dried paint on the knife edge to drag that scratch through a swath of paint that was supposed to be a pristine shiny surface. It takes more time thinking about the knife strokes than actually making them.
As always, I enjoy your comments, critiques, suggestions and questions.