When working from the smaller plein air painting, I have the colours of the situation stated for reference. What is missing is the amount of information required to make the larger studio work read according to the small painting. This can be achieved by "inference", meaning that detail can be stated without being picky - using texture, colour within masses, edges, gradations etc.
Using thumbnails requires more imagination. The colour reference is in word format and the main information is in the form of value masses with notes on the light key and direction. In order to make a larger painting out of this reference it helps to have plenty of on site experience - it builds colour memory, and a free imagination.
Using both of these approaches in a series is difficult regarding consistency.
This painting was done from reference derived on a hike at Cape Onion Newfoundland. Several small studies were also made in the area.