Yeah I'm a digital artist. People in the comments are mentioning Bob Ross but as lovely as his paintings are they are nowhere near as detailed as this. This canvas is 3 x 6 feet long, and you have to use progressively smaller brushes to polish a painting enough to achieve this level of realism.

I HATE when people doubt artist skills but as an artist who has seen a lot of art (and unfortunately a lot of stolen art) I am a bit skeptical. If OP is the artist I'd love to ask them more about their technique or see a process video. This looks like a painting with dozens of hours put into it.

EDIT: If this really is Dimitri Sirenko then I recognize his work! Unbelievably stunning. 11 hours still seems incredibly short for an oil painting of this size and detail - tell me your secrets.