Here is weight distribution on a large Hermagis, which covers a size more than 8x10!
lens cap (pill box type). 0.517 kg
barrel including hood. 1.904 kg this is more usual as there is an extra thread for a flange (Double-ender)
brass sleeve. 0.810 kg
lens cells with glass. 1.200 kg
This approaches5 kilos. The available petzvals are grossly over engineered. The early telescope makers made do with formed card and paper, and many survive to this day.
Here are photos of a 13" Wollensak Vitax (Petzval) that weighs over six pounds mounted to a 7x11 Eastman View No. 2.
In the close-up image, you can see the support that I knocked together. The support screws up tight under the lens and transfers the weight from the front standard to the front rails. The Eastman has a tripod mount that allows it to slide back and forth on the rails so that you can put the tripod under the camera's center of gravity. That is pretty important with that much weight forward. I seem to recall that Jim Galli shoots an 18" Wollensak on his Eastman View No. 2.
Where there's a will, there's a way!
Cameron Cornell
Washington State
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