Posts Made By: Gary Davis

Anthony,

Are you sure the focuser is the problem ? I own an Orion XT10 and the focuser is just fine. Let me say, the XT10 is just plain hard to focus but not because of the focuser. I can however use a laser to "help" alighn the scope. The XT10 does not produce images as well the other XT models. Not very good at all on planets except on the best of nights and even then its just so-so. Its hard to focus because it never has crisp images, expect soft images with this scope, rarely 250X. Time will tell you just what this scope can do. IMHO, the XT8 stomps the XT10, in fact the lowly little XT 4.5 is just as good as the XT10 when it comes to image quality. I also have found that the XT10 takes at least 1 1/2 hours to cool down, expect extreme difficulties in focusing until its cool. Great on deep space, but again, soft star images. I prefer the XT8 over the XT10, much better images and fast cool down. Good luck. I really don't think a new focuser is the answer. With this scope its inherent.

Brooks,

How much current "in amps" does this rig require ? The laptop will need about 2-5 amps. The camera, I don't know but to calculate the battery size needed is easy with this formula. Amps X hours needed + 20 percent "if using an inverter". Thus, amps=1 X 10 hours of use=10 + 20%= 12 amp hours. As you can see it will require a large battery of around 40 amp hours "4 amps for 10 hrs or 8 amps for five hours" and heavy. What about recharge ? If your still there in daylight you could use a solar panel of about 50 watts otherwise some type of generator would be required. A small 300 watt generator would weigh no more than a battery but would still need gas and oil and the noise will drive you nuts. But considering what you need a generator may be the best idea. It really all depends on how much current you need. Try not to use an inverter to reduce wasted energy. Also, some batteries cannot maintain high discharges for long periods of time "ie car starter batteries". Wiring is also a consideration for high current low voltage applications. I think the generator wins !! I don't think Nicads and cadmium batteries will fulfill your requirements. Good luck........!!

James,

Your 1.25" secondary is a 16 percent obstruction. Using a .75" secondary will be a 9 percent obstruction. Your focuser will have to be at least 2.5 inches and you need a 9 inch tube. Your secondary holder needs to be the same size as the secondary or smaller. You alraedy have a 1/20 wave secondary. You would have to consider that in your decision. But its, as far as I can tell, do-able.

You should be able to resolve M-3 with your 9mm EP "163X". I can resolve most of the stars with an 8inch reflector at 120X. You may have to use averted vision to see the tiny stars. In very dark skies you may be able to see some structure in the larger and brighter galaxies. In my 10 inch f/10 refractor at 250X "10mm" M-3 is resolved deep into the core. Some structure of M-51 can be detected and a handful of other brighter galaxies. Even my toy, XT 4.5 can resolve some of M-3. nearby is M-53 and is a little less condensed but dimmer. Let us know what you see.......

Heres the address of a very fine program www.cpac.org.uk. Its called planets version 2.02 and includes Saturn. Its a jiffy and will show everything you need to know about Jupiter. The program will reside on your computer and its free. The GRS will be yours after using this program as it shows where it is at all times. Good luck...............Also plots shadow and jovian moon transits.

Brian,

I have the Orion XT-8, love it..

The others you listed, I just do not know. Hope someone will chime in !!!

Roger,

See this add, 185609 it will enlighten you.

I have a series 500 made by Meade if that helps. It does not seem to be a super plossl and has a small field of view at least with the 30mm I have. But it is sharp to the edges, most likly due to the narrow field.

Fernando,

Its a prism diagonal.

Thank you for the info Michael. Sorry about your clouds. Right now its crystal clear skies for us here in the central valley. Hope it stays this way for awhile.