Thinking About a New Scope? Think Big!
Think Big
A lot of observers must like astrophotography - the 8" Schmidt-Cassegrain is a popular telescope. We offer an alternative: real-time astronomy, actually seeing details with your own eyes.
Consider M-27, the Dumbbell Nebula. In an 8" you need averted vision and an active imagination, or a long time exposure. In an Obsession 15" or 18" the Dumbbell is bright and huge. In an Obsession 20" or 22", the outer edge detail is phenomenal. And using an Obsession 25" is almost as good as being there!
See the M13 Comparison below for a good simulation of what you can see with an Obsession telescope.
Our telescopes' excellent optics and optimized overall design allow use of high magnification with maximum contrast for stunning visual images. Forget about faint and fuzzy and start getting used to bright and sharp. One look and you'll be hooked!
Many first-time telescope buyers get seduced by slick multi-page ads in magazines that sell small aperture Schmidt-Cassegrain Telescopes (SCT). These mass produced telescopes utilize a folded optical design to save space and money. They all have a large 33%+ central obstruction, small primary mirror and a corrector plate that eats up and distorts light. The result is dim, dull images and a disappointed customer. (Most of our customers are former SCT owners that have seen the light, so to speak!).
Comparisons |
Typical 8" |
12.5" |
15" |
18" |
20" |
22" |
25" |
|---|---|---|---|---|---|---|---|
| Light gathering power over typical 8" Schmidt-Cassegrain | - | 2.5X | 4X | 5X | 6X | 7.6X | 10X |
| Limiting stellar magnitude: | 14.0 | 15.0 | 15.5 | 16.0 | 16.5 | 16.7 | 17 |
| Rayleigh Resolution Limit: | 0.68 arc seconds |
0.38 arc seconds |
0.36 arc seconds |
0.31 arc seconds |
0.27 arc seconds |
0.25 arc seconds |
0.22 arc seconds |
| Contrast Limit: (minimum diameter before a nebular object fades from view) |
11 arc minutes |
6.0 arc minutes |
5.7 arc minutes |
4.8 arc minutes |
4.3 arc minutes |
4.0 arc minutes |
3.4 arc minutes |
18 Classic arriving for Ron Lewis in Brandon VT
The 15" Obsession has 4 times the light gathering power of the popular 8" SCT yet costs about the same. What's more, the Obsession 15" is a pure Newtonian telescope. It doesn't have any of the SCT's optical disadvantages. The Obsession 15" is a dedicated visual telescope. The result is bright, exciting images and an enthusiastic astronomer. Easy to set up, the eyepiece height is always less than 5 feet off the ground. It features the same award winning design and quality that has made Obsession the standard by which other Dobsonians are compared. If you and your family want to be turned on to visual astronomy, get an Obsession 15" and really see the Universe!
OZSKY star party in Australia - www.ozsky.org
