To obtain North-up, East-left on Clio images, you need to rotate your images COUNTERCLOCKWISE by the following:
DEROT = ROTOFF - 180 + NORTH_CLIO
where ROTOFF is the keyword in the header file (= PARANG when the rotator angle = 0).
Get NORTH_CLIO at Astrometric Calibration
Katie Morzinski, 2014/07/16
Modified 2014/09/25 -- Typo in angle, fixed. Was OK at http://zero.as.arizona.edu/groups/clio2usermanual/wiki/07e7e/Orientation_true_North.html