Sketches v Photographs
Photographs are very important reference material. The only downside of them is they can be very static. They can deaden shadows and colour. They can include an overwhelming amount of detail. A quick pencil study can catch the immediacy of the view. With a few carefully chosen, deft marks you can suggest:
USE OF THIS SKILL
A pencil study can be used on its own or alongside photographs. Both give important and different information. If you have managed to record plenty of information in your drawing book you will have enough to create a painting from it.
Your style of painting will develop and so will your use of quick pencil studies. It you are fascinated by the shapes and tones created by strong shadows this is what you will strive to capture.
A valuable study can take a few minutes to half an hour or so.
Recently I was sitting in cafe. I challenged myself to capture some of the figures around me. Those seated and having a rest I could spend longer observing. Those stood in the queue had to be captured in moments. Their pose had to be conveyed with a few lines. This is true also of waves breaking on a beach. Or the sun finally sinking behind an island.
Do you like doing a careful drawing before you paint? Yes -then your studies need plenty of detail.
Just remember the more you practice the better you will be at capturing and recording the part of the landscape that fascinates you.