Schmitt-Cassegrain Collimation Made Easy Using a Duncan Mask

Diagram-for-use

For any telescope to perform at its best, the optical elements must be aligned. With its magnifying secondary mirror, a Schmitt-Cassegrain is particularly sensitive to collimation. This process can be made quite simple by using a Duncan Mask which is very easy to make yourself and it removes the ambiguity of whether you have the optical elements precisely aligned. Click to read more

Prettiest Colour Contrasted Double Stars

Double Star image

I am a deep space junkie. But modern city living means light pollution often gets in the way of observing DSOs. Over the last 12 months I have undertaken a project to observe hundreds of double stars and I have selected my top 35 choices for colour contrast which in my opinion present a striking and memorable view in the eyepiece. Click to read more