The Rosette Nebula - C49

The Rosette Nebula is just to the East of Orion, but is extremely difficult to see visually. The open cluster of stars in the centre (Caldwell 50) is readily visible and is used to check that the telescope with camera are pointing in the correct place.

This image taken 7 March 2012 is the first image taken with my new William Optics Megrez 72 telescope and fitted with a William Optics 0.8x Reducer III(2011). It was taken as a test to see the wider field compared with the Megrez 90 and if the reducer was also effective as a field flattener. In both respects it seems to have done its job. It was intended to also take RGB images so that it was in colour but that is too late this time and will have to wait until next winter.

Exposure details: 18 x 10 minute guided exposures (= 3 hours total) through the refractor at prime focus with an Atik 314L+ CCD camera. Bias and flat field frames also taken. A Baader 7nm Hydrogen Alpha filter was used as this region is rich in this wavelength and the filter is very effective as a light pollution filter.