I have always loved to paint landscapes.
In my younger and more adventurous days it was plen-air painting out in the open which I still consider a very useful learning experience. The sun moves and so do the shadows and you have roughly two hours maximum before light changes start to impact on your work. You have to learn paint fast and organise yourself before you set up your easel. I used acrylics for the quick drying and easier portability.
Nowadays, as most people, I use photographic references and small pencil sketches with colour notes. Most of my work is done in the studio, but I still need to be physically present on site at least initially to have the ‘feel’ of the place. I have occasionally painted a commissioned landscape from other people’s photo source, but I was never comfortable with it.
Apart from underpainting in acrylics sometimes I work almost exclusively in oil.