The long nights are drawing in, this means longer imaging sessions and unfortunately colder temperatures. The later poses no problem for me now, I have a warm room in the observatory with a heater, before having the observatory – I would set up outside on the patio, wrapped up like an eskimo and still feel cold. Last night was clear, so I captured the OIII data for IC1848, the Soul nebula, even with 600 second exposures not a lot of OIII detail was evident – just enough to give some blue to the image.
Moving on to the California nebula, NGC1499, I changed to the SII filter and lowered my exposures to 300 seconds, this is a fairly bright nebula and long exposures are not needed, This was added to the Ha data to create a Bi-Colour image.
I didnt change to the OIII filter to finish this nebula, I wanted to get some Ha data on NGC2237, the Rosette nebula before dawn arrived, staying with 300 second exposures, I managed to capture 25 light frames – more than enough for stacking, that’s when I realised that the nebula was upside down from the usual way its viewed ( I had rotated the camera to get the california nebula on the diagonal across the imaging chip ) and that changed the way it looked completely, now it looked more like an early human skull. This must be the way it’s viewed from down under.
I would love to hear from southern sky imagers, to see if this has been noted before.