Friday, December 28, 2007

Thursday, December 27, 2007

Sixth Mars of the Year (Dam Mars)


Shot this one through Barry's 10" LX200GPS at the dam last night. It was dam cold with the wind blowing.

Friday, December 21, 2007

Fifth Mars of the Year



Almost didn't stay up to shoot this, but I'm glad now that I did. Best one yet.

Thursday, December 20, 2007

Fourth Mars of the Year


Mars' closest approach to Earth was this week.

I was feeling bummed about this picture, thinking I should be getting more detail until I looked at this simulated view from Calsky of Mars through a 10" telescope:


I guess mine's not so bad after all.

Sunday, December 16, 2007

Third Mars of the Year




Shot this at 1:20 a.m. when Mars was directly overhead. The forecast was for poor seeing, but I think it was probably between 3/5 and 4/5--not perfect, but much better than I had hoped it would be. 1500 frames with the SPC900NC in the LX200.

Horsehead Nebula


Not the definitive image of this object, but definitely one of the more difficult things I've ever attempted. The red cloud that provides the background for the horsehead is composed of ionized hydrogen, and glows in a specific color that the stock Canon Digital Rebel XT is almost blind to. That means I had to stretch this image like salt water taffy to get it to show up. On the other hand, the Flame Nebula to the left looks pretty good.

Shot 30 x 3 minutes through the AT80EDT piggybacked and guided with the LX200. Had some trouble with the declination guiding (should have just turned it off) so I tossed out about a third of the images. Now that I see what I can get from my back yard, I really want to shoot this again from darker skies.

Thursday, December 06, 2007

Second Mars of the Year



Better seeing, but I just couldn't stay up late enough to let Mars rise overhead. It was just above 45° altitude when I shot this.

Wednesday, December 05, 2007

First Mars of the Year



Not the best ever, but you can tell what it is. Seeing between 2/5 & 3/5. I was hoping it would get better as it got later, but it didn't. I still like the SPC900NC, and the new version of EquinoX worked better than I thought it would.

Tuesday, December 04, 2007

Repairing the Meade LX200 RA Drive

Finally, we've gotten some good, dark steady skies. Just in time for the 10" LX200 Classic to go belly-up. Well, maybe not belly-up, but it wasn't happy. At start up, when the RA drive is turning to align the worm gear, I was getting an awful "clackety-clackety" sound. Then once the drive setteled into RA tracking, it would skip or hiccup every 7 to 9 seconds.

A couple of months ago I had disassembled the entire RA assembly and re-lubricated it. I had been getting a high-speed vibration while tracking that I was attributing to "old grease." (Now, I'm not so sure that was the problem, but it's nice to have the worm and RA gear re-lubed anyway.) When I heard the noise, my first thought was that I had somehow made a mistake when I reassembled everything. Didn't seem likely though, as the scope had been running just fine. Then it occurred to me--this latest problem only showed up after the weather had gotten cold. Just the same, I removed and reinstalled the RA motor/gearbox assembly. No change. But blowing the hair dryer on it for a few minutes would cure it! Auugh.

So it's off to the internet and the Meade Advanced Products User Groups (MAPUG) archives, where I find a description of exactly what I was experiencing. Hooray! The fix? Adjusting two potentiometers on the motor control board. "No problem!" I thought. Then I read where the job requires a dual-channel oscilloscope. Drats.

But I kept reading. A little further down the page I found a link to Bruce Johnston's Astronomy Pages, and his instructions on repairing the LX200 drives using just a multimeter. Hey, I have one of those!

A short trip to Radio Shack for a few bucks of supplies, and I was off. I was getting pretty good at removing the motor assembly by now, and soon I had it sitting on the kitchen table. I followed Bruce's instructions and connected two batteries and the multimeter, and sure enough, the numbers were out of whack. Adjusting the two pots was simple, and after disconnecting all the wires, I reassembled everything back in the base of the scope. Guess what?

It works! Just as soon as I finish this, I'm off to the observatory to attempt making this year's first Mars image. Wish me luck.