Schiefspiegler kit, anyone tried it?
Posted 10 April 2013 - 08:45 AM
Has anyone tried it?
Posted 10 April 2013 - 09:04 AM
Posted 10 April 2013 - 09:38 AM
Posted 10 April 2013 - 11:47 AM
Posted 11 April 2013 - 07:20 AM
Some of the ATM opticians here could do better, I'd think.
The popularity of f/20-24 Schiefs in Europe must be based in the bright sky background from light pollution.
Posted 11 April 2013 - 08:00 AM
And stay in business, pay taxes, and put beans (not steaks) on the table?
Try it, sometime!
Posted 11 April 2013 - 04:52 PM
Posted 11 April 2013 - 06:56 PM
-Image quality certificate
for a 4.25in f28
Posted 11 April 2013 - 08:27 PM
Posted 12 April 2013 - 03:20 PM
Posted 12 April 2013 - 04:44 PM
Thank you, the optical performance is excellent in a Delmarva Schiefs. Yes it was displayed at Stellafane in 2005, it also won first that year in the optical judging for "complex optics".
If that's the one I looked through at Stellafane back in '05 or so, it's a stupendous scope. However our club member Lennie took the optics award that year. I thought the view of Mars in it was as good as the view in the winning 6" Newt.
Posted 12 April 2013 - 04:53 PM
Posted 12 April 2013 - 05:26 PM
You might be able to tease out a little better optical performance by going with a different radius on the secondary. Then you give up the fact that the tool used to grind the primary becomes the secondary and the primary mirror when figured to the needed sphere becomes the test plate for the secondary. One main reason why this design gives the outstanding performance that it does, is that both surfaces are spheres and have same radii so the primary can be nulled tested with the simplest of equipment, and then used as a test plate to figure the secondary. The result is that the average ATM has a real good chance of making the optics to a level of perfection that the performance of the scope will be what theory shows it can.
Posted 13 April 2013 - 06:39 AM
Posted 13 April 2013 - 06:57 AM
Posted 13 April 2013 - 11:00 AM
This design is proven, easy to build, and inexpensive. Most of mine was made from scrap yard pieces, but even if you buy everything new it's still not that much.
All the--simple--information you'd need to make one is available here, as well as help from a number of experienced members.