[OneCosmos (Chris)]

Hi,


I have one of Peter Miller's excellent light boxes to take my flats. This is my second box and I have used my first one many times with both telescopes and camera lenses, using astro cameras and DSLRs.


I used the new box for the first time this morning to take some flats using the Canon EOS Ra and the Sigma 105mm f/1.4 lens that i used to capture comet Leonard last night.


Unfortunately the light box with this setup produces a weird banding I've never seen before - see photo. Peter is at a loss so just wondered if anyone here can think of what the problem may be.


Cheers,


Chris