Quote:
Originally Posted by Satchmo
Conicals are about fast cooling.and convenience of mounting.Ive never seen one any lighter than a standard 1.6 inch plano blank in the same size and conicals usually quite thick in the middle.
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Hi Mark,
I have to disagree re the weight.
I have a 12.5" conical, and while I don't have a similar sized 1.6 inch standard mirror to compare with I cannot see how the conical can possibly be heavier?
Assuming the mirrors are made from the same type of glass, and that the parabolic indentation is the same, we can just calculate the two volumes.
Here are the dimensions for my conical:
Outer diameter: 12.5"
Edge thickness: 0.5"
Max thickness: 1.75"
Diameter of flat back: 4.2"
I then get:
Volume of conical mirror = 110.55 cubic inches
Volume of standard mirror= 196.35 cubic inches
The weight of my conical is under 5kgs (I think ~4.5kgs from memory) and this light weight, compared to a standard mirror, is what allows me to keep the whole setup riding on a cheap Losmandy G-11 mount.