A radiometric calibration for the Clementine HIRES camera

Abstract

We have successfully characterized the Clementine HIRES multispectral sensor entirely from inflight measurements. Relative calibration is obtained through dark subraction (additive) and sensor spatial nonuniformity (multiplicative) on a pixel-by-pixel basis. Relative residuals from frame-to-frame are typically less than 1% . Absolute coefficients are obtained through comparisons with calibrated Clementine UVVIS images acquired nearly simultaneously with HIRES sequences. Residuals between the coregistered UVVIS and HIRES calibrated images are typically 5% but may be as high as 20%. The residual is found most likely to be the result of increased scattered light in the UVVIS relative to the HIRES. Application of the calibration allows for seamless mosaicking of monochromatic and color sequences aiding in interpretation of surface features of the Moon at the scale of about 25 m/pixel. The calibrated HIRES color sequences represent the highest resolution spectral image data of the Moon.