Posts Made By: Dan Goldberg

April 7, 2003 05:17 AM Forum: CCD Imaging and Processing/Solar System

Any use for a wedge on a GPS scope?

Posted By Dan Goldberg

You can't really be polar aligned at all on the LX200. I can't imagine how you're able to take 90 sec shots on that system (in its stock configuration) without experiencing field rotation - I would assume 30 seconds was the best you could do and 60 seconds would really be pushing it. You could get a field de-rotator to counter this, or you could get a wedge and turn your mount into an equatorial one in which case field rotation would no longer occur. Of course you could still experience tracking errors depending on how well you align and how well your mount tracks.

With a perfectly aligned equatorial mount of ideal mechanical quality and tracking rate you could theoretically shoot unguided shots indefinitely. I don't think there's a lot of mounts like that out there smile

April 7, 2003 08:11 PM Forum: Off Topic Discussions

Al-Jazeera

Posted By Dan Goldberg

I saw some of those translated clips of Aljazeera that CNN was playing at some point early on and I thought they represented things quite fairly, just more conversvatively than CNN. A good thing by my account.

April 10, 2003 04:01 PM Forum: CCD Imaging and Processing/Solar System

D60 m101 3-24-03 (What's the blue thing?)

Posted By Dan Goldberg

I believe that you've captured conclusive proof of Planet-X. smile

April 13, 2003 07:18 AM Forum: Equipment Talk

Konus 1793 help!

Posted By Dan Goldberg

If the telescope starts off moving slowly and then speeds up when you push the buttons on the controller, that's probably backlash compensation. With regards to the tracking problem, are you sure your batteries are OK? Correctly polar aligned? Telescope's properly balanced?

I don't know what you can do about the focuser except replace it with a better one as you suggested. You might try cleaning and relubricating it and/or shimming it in some way. With regards to the EQ-6 mount, from everything I've heard it should be a world better than the EQ-5, but you may discover that it's unnecessary if you can track down the problem with your EQ-5.

April 14, 2003 06:57 PM Forum: Deep Sky Observing

Viewing the Red Spot

Posted By Dan Goldberg

Are you sure it's visible when you're viewing? I know it's the old have you got it plugged in question, but I have to ask smile I was able to pick it out of some modest seeing this winter with my 4" Mak.

April 16, 2003 03:48 PM Forum: Deep Sky Observing

Thanks for the GRS Information

Posted By Dan Goldberg

With any luck you won't have to wait too long smile Best of luck.

May 1, 2003 03:53 PM Forum: Equipment Talk

what does triplet mean?

Posted By Dan Goldberg

An achromat is typically a telescope that focuses two light wavelengths to the same point whereas an apochromat is a telescope that focuses three to the same point, the objective being to remove chromatic abberation (ie. false color). A doublet is a lens with two elements and a triplet is one with three.

Most standard refractors are achromatic doublets whereas most high end ones are apochromatic triplets.

May 20, 2003 10:03 PM Forum: Off Topic Discussions

Anti-Spam

Posted By Dan Goldberg

Does it filter out the funny ones too? There's some quality spam you are potentially missing out on!

May 22, 2003 03:24 PM Forum: Equipment Talk

Inside Condensation

Posted By Dan Goldberg

Could you heat up the scope and let the moisture evaporate out?

May 27, 2003 01:54 AM Forum: CCD Imaging and Processing/Solar System

Need help in coupleing camera to scope

Posted By Dan Goldberg

Well, the NS4 is a slow and long telescope. If you were to do the math I wager you'd be seeing magnifications in the 250X+ range. Maybe a focal reducer is in order, or perhaps you could try shooting through the camera's lens assembly?

I don't know, because I've never done it, but maybe someone who has can elaborate on my line of thinking or else negate it smile