For those of us on a tight budget who would like to have an aluminum dew shield instead of a plastic one, you can purchase an aluminum tube from Hastings Pipe and have a aluminum dew shield for around $52.00. The one I have is 12" long. All you need is a little paint and some adhesive felt. It stable in the wind and is easily attached or removed.
I only needed three pieces of felt but the six are shown for clarity of the idea. It's a nice slip fit. Be careful not to be too aggressive while inserting it. Otherwise you will have to collimate the secondary. This is for C-11's only.