I made several modifications to the tripod
in order to improve the functionality a bit. These are highlighted below,
- painted white all the parts you have to find and touch in the dark
- replaced the front azimuth control thumb screws with Allen cap bolts
- Velcro on hand control to stick it conveniently to the tripod legs
- drilled holes tripod base for azimuth and altitude adjustment hex wrenches
- drilled and tapped holes in side of tripod to hold LX50 baseplate attachment screws (detail below)
- hole in tripod base for baseplate attachment hex wrench.
Detail showing placement of screws. A slightly
undersized hole was drilled. The screw itself was used to easily cut threads
into the soft aluminum tripod.
The cross hairs in the tripod were also
replaced with a ring of my own design, consisting of a small metal ring
taken from a piece of jewelry and individual strands from 22g stranded
wire, all carefully soldered together. The center section was clipped clear
after soldering was done. The entire mess was then coated with glow-in-the-dark
paint. Cross hairs have always bugged me because the dark wires are impossible
to see under truly dark skies and when you get your desired object exactly
where you want it, you can no longer see it. With this, a second or two
of shining the flashlight through the finder, and an easily seen (if slightly
ugly) ring is visible against the sky. The object can be exactly centered
within. Perfect for photography, where I can't see through the eyepiece.
I also wrote a simple program that computes
the altitude and azimuth correction required for perfect polar alignment
after measuring the drift rate on any two arbitrary stars. Like the standard
drift alignment method, accuracies are best when they are at right angles,
but the math works for any two stars. I measure the drift rates (arc sec/sec)
using my Quickcam 3000 and K3CCD tools, but timing drift across the eyepiece
works just as well. The program computes error in alignment, as well as
how many turns of the altitude and azimuth adjustment screws are required
to get where you want to be. (my azimuth alignment threads are nonstandard,
however.) Given the RA tracking error, it's easy to get adequate alignment
within a few minutes. K3CCD tools helps get the declination drift rate
Lastly, if you are interested, here is
a plot of my periodic error prior to any polar alignment. It is a bit more
and a bit faster rate than I had hoped for, but there are periodic (pardon
the pun) sweet spots where 30 sec exposures can be tolerated. With patience,
I can gather enough for a reasonable image.
There are of course many other tips out
there, but these are mine for now.