Characterizing the KL4040 sCMOS camera for use at the Boyden Observatory

Recently the marked improvement and availability of scientific CMOS (sCMOS) cameras has provided an alternative to more expensive CCD based cameras. A Kepler KL4040 sCMOS has been acquired from Finger Lakes Instrumentation to replace the current CCD camera used on the UFS Boyden 1.5 m telescope. Because of the differences between CCDs and sCMOS sensors, the sCMOS camera is currently being characterized and tested. The camera was first mounted to a 14” Celestron CGE 1400 system with an Apogee FW50-7S filter wheel with Johnson-Cousins UBVRCIC filters for the first on-sky and star-light tests. These included absolute photometry of the standard field SA107 in the BVRCIC filters using differential photometry and using the determined colour coefficients. Thereafter the camera was moved to the Boyden 1.5 m telescope and mounted on the Photometer Instrument-pack with a Johnson-Cousins UBVRCIC filter system. After integration into the Boyden 1.5 m telescope systems, additional on-sky tests were performed, including fast photometry of one full orbital period of 3.56 h of the cataclysmic system AR Scorpii at ≈ 6-7 s cadence. All of the results were processed using a custom python pipeline created using libraries including astropy, numpy and ccdproc.