In this paper, we propose a method for measuring the Bidirectional Reflectance Distribution Function (BRDF) of real planar materials using a simple apparatus. Our proposed method uses two handheld cameras, a light source mounted on one of the cameras, and a box with markers attached to each face. A planar material is placed on the box and the user acquires video images of the material while moving the two cameras around the material. The system obtains a sampled BRDF using the light source and viewpoint positions and pixel values at a certain point on the material. Then, a dense BRDF is estimated by interpolating the sampled BRDF using the technique of compressed sensing. The experimental results showed that the proposed method can reproduce the reflectance properties of real materials. It was also shown that compressed sensing was more suitable than RBF interpolation for estimating dense BRDFs.