With spring around the corner I'm getting organised to do more painting outdoors. Trevor Chamberlain immediately comes to mind because he is an enthusiastic 'plein air' painter. It's interesting that his 'plein air' watercolours are mostly small; 7in x 10in or 14in x 10in. I've taken these dimensions from the illustrations in his book 'Light and Atmosphere in Watercolour'.
Largely self taught Trevor Chamberlain describes Jack Merriot as one of his heroes. Merriot wrote 'Discovering Watercolour' a manual on watercolour painting. Long out of print but worth buying second hand if you can find a copy.
I've discovered a very informative website:- Watercolour New Zealand Inc. which has articles about several watercolour painters including both Trevor Chamberlain and Jack Merriot. The website is worth a long look. The link should take you to a list of articles about Chamberlain and Merriot.