Psychedelic SSTV on 255.560MHz

I was having a rummage around in the UHF Satcom band when I noticed an unusual signal on the 255.550MHz transponder downlink.

It turned out to be analogue SSTV, Robot 36 mode, over FM centred on 255.560MHz.

It seems to repeat the same image for quite a while.  So far it has sent these pictures, received with QSSTV:
 

The colour looks worse than NTSC :P  I'm not sure why it is so bad.  Similar reports have been noted here and here (forums.radioreference.com) and on youtube here.