Cloud cover is a serious problem for remote sensing in Indonesia. Some areas around 10-20% of the land territory are almost never cloud-free. The only system of remote sensing capable of overcoming cloud cover problem is that applying microwave energy. This article deals with a radar system being operated by the Columbia SIR-A in 1981 in Batu Angkal area, West Kalimantan. The study is aimed at learning the interpretability of SIR-A images of 1:500,000 which is blown up to 1:250,000 for the study of environment of this area. Factors affecting the ease of identification are mainly tonal contrast, shape, size, surface roughness, direction in relation to the illumination, and dielectric constant. Due to the future availability of SIR-B image of Kalimantan, further study is recommended.