Anyone who paints or creates gets this question a lot. So, here and now, is my answer.
First, I get an inkling of an idea. I sleep on it for a couple of nights. (48 hrs.)
Then, I start do research for reference photos. (usually 3-4 hrs.)
Out of those say, 30 reference photos, I choose 2 or 3 to work from in a unique composition. (2 hours)
Next comes choosing the right size canvas and staring at it and the reference photos for an (hour.)
I then start sketching different composition ideas until I hit on one that intrigues me. (1 hour)
Time to actually begin to work on the piece physically. I sketch a rough outline of major shapes on canvas. (half hour)
Blocking in the underpainted values takes about (2 hours) if it is a med. to large painting.
From there, I must start to firm up my major shapes, all the while trying to keep the values harmonious, which requires constant tinkering. When I have the sky, middle ground (water or land), and foreground values somewhere near right, I start to work on the focal point of the painting, where the highest contrasting colors live.
By now I've probably spent about (4 more hours.)
The remaining time is spent adding detail, adjusting color and value, and adding more detail. This goes on for days (say, 4 days, or 20 hrs.)
Okay. The painting itself is done. Since I frame it myself, that takes another
hour, not counting the time to order the materials, etc.
So the GRAND TOTAL comes to: eighty-three and one half hours.
Whew, now I know why I'm so tired all the time. lol