Hi all. I've got a 8" LX200 at f10. Main use: attempts at CCD images with
the 416XTE.

I would love to thank all of you... I've been lurking for a while. I've
read so many articles, and I've learned a great deal.

Questions:

1) Focusing my CCD, I usually watch FWHM values in Maxim DL. What values
should I be able to obtain on good nights? The best I've managed has been
2.5 pixels.

2) My backlash correction is maxxed at 99. It's enough to avoid delay
switching directions, but the correction is so large the image jumps when
it starts. I've read about the DEC bearing mods... would this be worth
doing on an 8" scope? Is the small jump (half the diameter of the circle
in the 9mm illuminated recticle) going to affect me much?

I've done mods to the cheapest part of the setup... the wedge... replacing
the plastic knobs on the azimuth adjuster with allen head bolts and drilling
a hole through the end of the deluxe latitude adjuster screw and running a
nice long metal crossbar through it for easy turning. Oh, nylon washers
here and there too. Works great.

Doing mods to the scope itself is a much scarier thing. :)

3) Anyone have any idea how to focus the 201 autoguider on the off-axis
guider when using the 416XTE AND the color wheel? I couldn't extend the
barrel enough to manage it. I have yet to successfully use the autoguider.


A quick story:

I spent 3 and a half hours tonight setting up my scope. 3 and a half hours.
Why, you ask? Well, the night before I got impatient and rushed it... as
a result the only CCD image I actually saved was a single dark frame. So...
I decided THIS TIME I'd calibrate the scope to the absolute best of my
ability. Which, at present, isn't so much. :) Still, I was determined.
I wanted to near-perfectly polar align, re-collimate, PEC erase and retrain,
and focus to the best FWHM values I had ever seen.

You know what? I did it. Mars, which was basically featureless before
collimation, had really great detail to it. I finally understood drift
alignment and actually had it aligned out past 6 minutes before drift
noticably set in. I had a really good feeling about my PEC session... and
2.5 pixels FWHM was about my best ever focusing job.

Literally a minute or so from getting serious and taking my first image of
the night... I decide to grab the serial cable and connect my laptop to the
LX200 so I can easily see where my scope is pointing in Starry Night Pro.
Not sure which cable, I check the 416 manual I had handy (recalling it was
in there somewhere too), and following it's directions proceed to plug in
the black phone cable and watch my ammeter peg, then go black.

The power cord fuse is not blown. The spare power cord doesn't work either.
The AC supply through an inverter doesn't work. No... no way! Defeated, I
pack everything up and head inside. Dreading having to ship the scope to
Meade for repair, I decide to take the panel off and just check if anything
looks obvious. I grab my multimeter and a screwdriver and open it up.
What's just about the first thing I see? A fuse. Blown. I notice it's the
same fuse as the power cord fuse... so I take the fuse from the spare cord
and try that. 4 red bars... IT'S ALIVE!

You have no idea how scary that was. What really bugs me is how well the
scope was set up, and what great images I just barely missed.


Darron Black

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