One of my very first paintings I gave to my sister(back in late 60's). Some years after on one of my visits, I noticed it needed some work. Her husband's heavy smoking gave the whole thing a yellowed pall, and something had dripped on it. I took it home to give it a makeover.
After sealing with spray fixative, I went over the whole thing with fresh [Oil] paint; striving for better colors & composition.
I narrowed the river, rearranged pines, added a tree which looks dead, but I like the pattern of its naked branches. The red-earth foreground with abrupt cliffs did not belong in this misty-moist scenario. So they got covered over with grass & wildflowers.
After complete drying time a thin coat of damar varnish to protect its colors & give a slight sheen.
Even the frame got a fresh stain & varnish.