Days are now getting longer, but how do you handle all these long winter evenings or paint when you only have the end of the day available? The answer is simple: get a daylight lamp. The risk, if you paint under normal electric bulbs or tubes, is that your colours won't look the same the next day under natural lighting conditions.
My lamp is a an easel model from the Daylight Company. It is big (not for travel), with a retro look, and does the job perfectly. If you want to save money, you can just buy the bulbs or tube and fit an existing lamp. There is a range of bulbs and tubes available.
It is worth investing in one of these lamps if you have not done so.