Posted inAstronomy Telescope Mods & Repair

Nexstar SE Wedge

The final part of my Nexstar project was getting it on a wedge which would make auto-guided long exposure shots possible. Unfortunately, the Nexstar wedge has long since been discontinued and even if it hadn’t — $160 for a weenie little wedge for this scope was a bit much for me. So I decided to buy a cheap used wedge from an older Celestron system and make whatever modifications were needed to get it to work with the Nexstar.

What I didn’t expect was how little modification was needed to get an old 1980s era Celestron C8 wedge to work with the Nexstar SE. All the holes, both on the tripod and drive base lined up perfectly and the only modification I really had to make to the wedge was to hammer out the center guide peg.

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Posted inAstronomy Telescope Mods & Repair

Nexstar SE Camera Platform

I recently picked up a used Nexstar 6/8 SE mount and tripod. The idea is using it not only as a grab-and-go for my 72mm f/6 Orion EON, (and hopefully a 5 or 6″ SCT OTA down the line), but also in the hopes of using it for some lightweight wide-field long-exposure and time-lapse astrophotography.

I wanted to side-by-side mount a DSLR camera and wide-angle lens combo alongside my unused Celestron 9×50 finder scope from my CPC800 and use an Orion StarShoot autoguider attached to the finder to guide the whole contraption for long exposure photos. That this setup can run on batteries, and is lightweight enough to chuck in the back of the car for camping trips, made this an interesting camera platform despite the Nexstar’s well known astrophotography limitations.

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Posted inAstronomy Telescope Mods & Repair

Meade LX50 DEC Axis Issues

Hoo boy, did I have a sick DEC axis. I think I only began to notice it when I started guiding long-exposure shots as it was on the most part livable for the visual stuff.

I had a few problems:

  1. Reversing direction quickly back and forth several times would actually “crash” the LX50! The power led would start blinking and all I could do was power off, wait a few seconds and power on to get it to respond. Kind of like an operating system or two that I won’t mention here! 😉

  2. Speed of motion on the DEC axis had nothing to do with the RA axis. Either it was Speedy Gonzalez or the motor would actually come to a grinding (seriously — grinding) halt.

  3. When I reversed direction it would take a long time before whatever was in the FOV actually moved. It was like slack was being picked up somewhere in the tangent arm.

None of this is very good when you’re trying to guide a photo on a guide star you can barely see, and I won’t even go into what an autoguider will try to do…

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Posted inAstronomy Telescope Mods & Repair

Meade LX50 Hand Controller Fix

This happened to me on my 3rd night out with the LX50 and from what I’ve read elsewhere, it is a pretty common problem. In my case, some keys didn’t work, and the declination axis worked only in one direction. Don’t panic if this happens to you! All that’s going on is that a connector inside the hand controller has come loose.

If you open up the controller it should be pretty obvious what’s going wrong.

Remove the 2 screws on the back of the controller and pull off the back plastic panel. Inside you’ll find the circuit board connected to the front of the controller (where the keys are) by a blue connector. (Circled in red in the picture) This is what has come loose. Just push it back in, pop the back on, screw it in place and everything should be fine again.

I used some electrical tape over the connector and the back of the circuit board to keep it in place, and it has been fine since.

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Posted inAstronomy Telescope Mods & Repair

Meade LX50 RA Axis Moves Slightly When Locked

This one really spooked me. I was finishing up for the night with a quick look at Orion. I aimed, locked the RA and DEC, and noticed that with the RA locked I could move the scope in a left-right motion very slightly. More or less half a centimeter of travel. Yikes!

I took the scope inside and plonked it on the kitchen table with both the RA and DEC axis UNLOCKED. (This bit is very, very important! When you lay the scope on its side, you’re putting pressure on parts that weren’t make to take a lot of weight. If you have an axis locked you could force the scope and really break something.)

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