How long do you think it took Him to draw this background?
I love takumi's dedication but Man, no wonder he constantly burns out.
A single medium length line on the tree bark like that would take you at least 30 seconds after you have started drawing other elements of the drawing on a fixed perspective. Get that. A single line. (unless you are an art genius that can draw lines flawlessly on your first try, in which case it might be faster)
The tree leaves can be done fairly quickly if he actually uses a broad brush along with a nib pen to ink. Assuming he does that, he can probably make a fully leaved treetop in about a minute if he is comfortable with what he is doing.
The light and shadow contrasting might take longer if he does that on photoshop or something equivalent and depending on his skill might take him at most 2 hours as this particular picture is not that complicated.
All in all if he does not mess up his lines, I think he finished this particular picture in at most 3 hours (unlikely).
Unless of course he uses pre-made resources for his background then he can churn it out even faster.
Take experience into account -- Takumi is excellent at these kinds of backgrounds. Some of these might even be recycled, you know. If you snip/crop them correctly, you can basically just reuse backgrounds.
I was reading how Ken Akamatsu uses digital art to design his sets (Negima!).
