[quote:b0613cfdfc="tbob"]I also have a Canon HV10, the HDV quality is outstanding but coupled to a Swarovski scope, it appears that the camera is only usuable at the tele end of the zoom, this means it is 10x (on the camera ) and 20x or 30x (on the scope) depending which eyepiece you are using, so the total magnification is far to great for Hong Kong's polluted conditions.
The HDV quality of the HV10 matches the quality of the 3 ccd HDV cameras.
Bob[/quote]
I am lucky to have a special eyepiece for videoscoping. This eyepiece has full eye relief "starting" 20mm and beyond. So for HV10, there is only minimal vignetting after 4-5x and no vignetting after 8-9x. At full 10x, I guess the total focal length is around 5000mm in 35mm equivalent. I tried both the 23x/30x and the 20-60x eyepiece. vignetting start to disappear at 9x and beyond. I agree with you that this huge magnification is not too useful at all.
Videoscoping and digiscoping is a lot different in terms of vignetting. Most camcorder has 10x zoom and more. The entrance pupil of the lens pulls back rapidly on zooming, far exceeding the eye relief of the eyepiece. It ends up even more vignetting on zooming until in the very high magnification, the angle of view is so narrow that vignetting disappears. But by then the actual aperture is so small and magnification is so high that it is difficult to get a decent picture or recording. In that case a custom-made eyepiece is needed.