Quote:
Originally Posted by strongmanmike
Wrong page link for the corrected Newts
Here is the correct link (bottom paragraph) ...just so people are not mislead (again) |
OK...so you go there and download the .pdf, and that says:
"All ASA astrographs are manufactured from superior
Suprax glass material and polished to an accuracy
of P/V = 1/7 lambda etc.. ..................... on
request, premium Astro-Sital ceramics polished by
LOMO optics can be ordered"
Suprax as far as I can tell is a Schott borosilicate glass similar to pyrex.
Assuming Orion are supplying their pyrex optics one wonders why ASA don't mention this fact and continue to refer to LOMO
..anyhow, it seems pretty clear if you want zero-expansion optics, then they come from LOMO, not Orion.