VV report for obsid 18839 - Mrk 421

Review Status: warning
Comments: WARNING: this is a big-dither calibration observation, which used a large dither amplitude in the chip-y direction to map the response vs chip-y. Default responses (ARF) will average over the array. The LSF (RMF) is not calibrated for off-axis pointings (>~ 2 arcmin). There is a strong dither signal in the light curve.