All images were taken with an Orion Optics 200mm SPX F8 Newtonian reflector (8-inch) unless otherwise stated. This telescope is ideal for planetary imaging
due to the long focal length and resulting small secondary mirror, giving high contrast images. Additionally, the longer the focal length the easier it becomes to accurately collimate the optics, which then stay in collimation for much longer.
Another advantage is the large 11mm 'sweet spot' of an F8 reflector. This is the area where the off-axis coma has negligible effect even at high magnifications. One downside of this telescope is the very long tube which is easily shaken by the breeze.
Since 22nd October, I have been using an ATIK ATK-1HS monochrome air cooled astronomical CCD camera. This is basically a cooled version of the Toucam Pro webcam without the colour filters. This allows me to use separate colour filters which are plugged into a drawer unit attached to the camera. I use RGB filters from Astronomik, and also an IR filter (742nm) from the same manufacturer.
Typically, Mars imagers use seperate red, green and blue filters and combine the separate images into a resulting colour image. It is also common practice to replace the red with an infra-red (IR) filter. Before this, I used a regular Toucam Pro II webcam with an IR-Blocker filter. It is important to use an IR blocking filter with a colour webcam to prevent the IR light 'bleeding' into all three of the colour channels. I purchased my kit from Modern Astronomy, the proprietor Bernard Karpinski is extremely knowledgeable and helpful.
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