The observational works were painted in long sittings under the natural light from the windows in the studio. Calming and perhaps even meditational to paint, hopefully this also comes across to the viewer. Light and surface were the particular concerns and it is interesting how the pictures catch the blue tint of natural light in the Northern hemisphere. A phenomenon which presumably we have only become conscious of since the arrival of widespread electrical lighting with its harsh yellowy orange light. These works share with the later works an interest in perception, although in these works perception is limited to an optical awareness of perception, as opposed to perception with reference to the mind. Another interesting thing to note is the increasing frustration that these works produced with regards to trying to use full hues. In the later pieces coloured cards and papers were introduced to try and fight against the cold blue natural light. A situation that led to the abstract treatment of colour rather than representational, in later works.