Abstract
A Weissenberg camera screen with two slits for x-ray single crystal study was developed to record two layers of reciprocal lattice simultaneously. We opened the zero-layer in the lower half of the film and first-layer in the upper half by using crystals of aragonite and diamond. The computer program was made to analyze the reflections from the twinned diamond, and it is confirmed that this diamond is combined by spinel law. This attachment will be very useful for rappid determination of lattice constants and space groups of crystals, especially under unstable condition and radiation damage.
