Last night I had “first light” with the 12.5” f/6 mirror that you recently supplied. It is truly a magnificent optic! Ronchi, knife-edge, and star tests were straight out of a textbook, and the image of Saturn was breathtaking. Despite the thin substrate, there is no hint of astigmatism. Frankly, when I purchased a Hubble Optics mirror on xxxx, I was skeptical of the advertised wavefront quality. For the low price, it just seemed too good to be true. In the future, I will not hesitate to recommend your firm’s optics to friends and acquaintances...
-Tom Dobbins Contributing Editor, Sky & Telescope magazine (quoted by permission)
I’ve tried buying fast 8” mirrors twice through A-mart and both were dogs – terribly undercorrected, probably spherical. This mirror is way different. Stars are near pinpoints and there is no tendency to astigmatism (at least nothing that didn’t come from my eyes). I went out tonight and looked at Jupiter as soon as it became visible. Even so, it is getting pretty low in the sky and the air was pretty wavy. As near as I could tell, in the moments of stillness the images were as good as any scope I own.
Star testing showed even images that were very nearly the same inside and outside of focus. Using my EZ tester (ronchi eyepiece) showed nice straight lines and no hint of TDE.
As far as I can tell this mirror is a winner and will suit my needs very well. Whether or not it actually meets the specs listed on the box I can’t tell without getting it tested. But its a lot better than the other Ebay mirrors and I like it. I wouldn’t be afraid to buy another Hubbleoptics mirror...
-Dave Chadsey (posted at http://www.cloudynights.com)
A real piece of art (14" lightweight sandwich mirror)...
I just tentatively assembled my 10" F4.7 1/17 PV wavefront mirror in my observatory and watched Jupiter and the moon last night. Although the air condition was terrible due to middle of rainy season, optical performance was exactly as I expected! The surface of Jupiter was amazing. Contrast of color was deep and details were very sharp, image edge was knife cutting, even through hazy bad seeing. The surface of the moon had an extra contrast; very very sharp edged landmark was attractive enough to keep watching hours. A hair splitting and breath taking experience, which reminded me of previous mirrors. I need to further tune up optical performance of this scope such as replacing with smaller high precision secondary mirror etc. Will report further progress.
Just wanted to let you know that I received the 14" mirror. AND, we tested it today at my astronomy club. We used the computer program FigureXP, and created a 7 zone mask for it. We used a very accurate Foucault tester with a video camera. I must tell you that the mirror was better than I expected… I am VERY happy with this purchase!
Took a while for the mirror (14") to come in, but well worth the wait!
Totally dependable seller (20")
Dave Sommerfeld (right) with his UP12, 2017
" I want to express my admiration for your excellent optics. It gave us a lot of pleasant hours under the southern stars."
But the deep sky objects…wow, I truly have never seen Orion like that, the entire 30mm eyepiece filled to the brim with nebula, the colors, the tiniest of stars in the trapezium, I must have looked at that for over an hour, 30mm 82 degree, 14mm 100 degree, 24 and 16mm in binoviewers, holy cow! The spiral structure in galaxies, the Eskimo, the Owl, etc, all kinds of stuff, just a heck of a lot of fun and most likely the best views of objects I have ever seen…certainly the most in one night.
"UL20 is working excellent. The mirror quality is excellent..."
-Hiroaki Nakamura with his UL20
Hello Tong, Wanted to take the time and say thank-you for the excellent 20" f4.2. Wow is this mirror smooth and precise! Had one chance to see Saturn low in the sky, in September with stable seeing conditions. Uranus is finally getting higher, to chase good seeing. Where I am located south-west of Buffalo NY near lake Chautauqua, mostly have the jet stream overhead and never have stable seeing, except in the summer months. The site where the scope is, is dark and the deep sky views outstanding! I counted 26 galaxies in NGC 507 group at 200x in Pisces-Andromeda border. I'm using a Denkmeier 2 binoviewer and 3 power switch and A45mm OCS -1.2x 1.8x 2.25x with 24mm panoptics (107x 160x 200x ) and 35mm Baader eudiascopics I special ordered from Germany, just for this scope. Also color is brilliant as blue-greens are in planetary nebulae with this mirror ! Looking forward to seeing the pink rim in IC 418 this winter !
Bill Porte's, His-n-Her's UL18s in the Sierra Nevada Mountains
Rick's and Peg's, His-n-Her's UL18s at Okie-Tex Star Party
Jeff Roberson's UL24
Jeff Roberson's UL24
Jeff Roberson's UL24