Posts Made By: Chris Deppe

I just picked up a nice C-11A OTA, but I'm stuck about what mount to get. The OTA is a newer #91036-XLT with the CGE dovetail bracket. I was told that this would also fit the CGEM EQ mount. The problem is that I can't afford either of these mounts. In fact, the CGE would be out of the question entirely, and the CGEM is out of my reach for at least a couple of years. I plan on doing some astrophotography with it. Probably about 70% viewing, and 30% imaging. At this point I don't have a preference as to weather I get an Alt/Az mount or an EQ mount, as long as it's stable enough to be useful. I'm not opposed to changing out the mounting bracket, if needed. I knew this would be a bit of an economic trap when I bought this thing, because you save so much money when buying the OTA and mount as a package, as opposed to seperately. But, I got it cheap, so I took on the challenge. If I can't find a mount by the end of spring, I will probably end up building my own manually operated mount so I can at least get some viewing in this summer. So my question is, does anybody have any reccommendations as to what type of mount I can get for less than 1200 bucks, that would be anywhere near steady enough for a 28Lb tube? Could I even get an Alt/Az mount for this scope? Any suggestions would be greatly appreciated.

I've tried to respond to two classified ads here, and I never got a response from either party. Is this a problem with my account, or do these guys just not want to answer their ad responses?

I posted this in "News", but I'm not sure if it will clear in time.


A new PBS Documentary called "400 Years of the Telescope. A Journey of Science, Technology and Thought" will be airing on Friday, April 10th, at 10:00PM ET. Check local listings, since your PBS affiliate may time shift this program.



Panoramic visuals and engaging interviews make 400 Years of the Telescope the must-see documentary of the International Year of Astronomy in 2009.

Beautifully photographed in 4K digital cinematography, the film is a visually stunning chronicle of the history of the telescope from the time of Galileo, its profound impact upon the science of astronomy, and how both shape the way we view ourselves in the midst of an infinite universe.

The film features interviews with leading astrophysicists and cosmologists from the world's renowned universities and observatories, who explain concepts ranging from Galileo's act of revealing the cosmos with a simple telescope, to the latest discoveries in space, including startling new ideas about life on other planets and dark energy — a mysterious vacuum energy that is accelerating the expansion of the universe.

Join us on this companion website to explore this fascinating subject as you meet the film's producers and their worldwide search for the world's greatest telescopes, enjoy captivating interviews with brilliant personalities, learn about planetarium programs in your area and discover local and faraway opportunities to experience our incredible universe firsthand.

Link: http://www.400years.org/

OK here's the background. I'm a beginner, or amateur amateur as I like to call it. I have a Celestron C-9.25 on a CGEM. Both were purchased used (here on Astromart). I knew I was going to have to collimate this scope after it was shipped to me, so it was no surprise that saturn looked very blurry upon my first sighting. This was with clear skies with decent viewing, and very little light pollution. I knew it had to be done.

I got a few more EP's and a Barlow so I had more choices in magnifying power. So I have tried to collimate this thing several times now, but I'm having trouble with the diffraction rings. As in, I can't see them very well, and when I use the higher power EP's, it just gets more difficult beacause the rings get blurry and closer to the outer edge. The rings just don't seem to be appearing in a concentric pattern, and are poorly defined. This makes it impossible to use them to center the CO. It actually seems easier to center the obstruction shadow at low power since the edges are sharper. I have tried using the following EP's: Celestron E-lux 25mm Plossl. Baader Hyperion-Aspheric 36mm. Baader Hyperion 8mm MC. And, Celestron 8 to 24 Zoom (#93230). I've tried all of these with and without a Meade Series 5000, 2X TeleXender in place. All in a Celestron 2" Star Diagonal (#93527). This is all with stars of varying intensity (tried a bunch). I can see the rings slightly better on the infinity side of focus, but not well enough to use. I will say that the focus assy seems to be VERY sloppy on this unit, but a can still get a very fine focus with a light hand. One other observation. The eccentricity of the shadow seems more pronounced on one side of focus than on the other. I can't remember which though. I have tried this while wearing my contact lenses, with my glasses and without any correction at all. The problem seems to be consistent over these scenarios. So what's going on here? Is there something wrong with the scope, or is it something else? I'm at the end of my rope with this deal. :C

I just recently procured a used C-9.25 and a used CGEM mount. Still learning this stuff, so no expert opinions here. I did have quite an adventure getting my scope in decent shape though. It had multiple issues. Story here: http://www.astromart.com/forums/viewpost.asp?forum_post_id=662244&poll_id=&news_id=&page=

Well, I'm not an expert on this, but I'll give it a try. Because of the tracking speed necessary, you need software that will drive your mount independently of the tracking rates programmed into the mount. As far as I know, the only "useful" satellite tracking software is the freeware program called "Satellite Tracker V2.4.9" This software uses it's own track/drive algorithyms to produce a track. It does NOT use ASCOM drivers, therefore the connectivity/support of your mount depends on what prorocol it uses. As far as I know, the SatTracker software it is only compatible with the following protocols: Meade LX200, 200GPS, and Autostar. Celestron Ultima, NexStarGPS, NexStarGT, and CGE/CGEM. If you want more info, go to the Satellite tracker Yahoo user group at (http://tech.groups.yahoo.com/group/satellitetracker/).