Astro-Barbi has reminded me to respond more promptly to those that have
sent personal e-mails to me. I am way behind do to several astronomy
projects and endeavors- many of the projects are behind-the-scenes in nature.
I'll try to answer all as quickly as I can. Astro-Barbie has also insisted I make
amends. From time to time, I will post some of my field notes which are on
topic and of potential interest to members of Mapug.

My colleague and I returned from a trip to South Florida finalizing a remote
controlled observatory. The AP-7 CCD camera and Paramount are the
workhorses at this site. Those two items alone are close to $20,000 US.
To put things in perspective, neither myself or my colleague have a financial
interest in this site, however, I have been invited to use the equipment for
scientific research works. I will likely do some semi-serious research
remotely from my home. I am both pleased and honored to be allowed
observatory time on this fine equipment.

I had the opportunity to spend an evening with the designer of the Paramount
using his 22" Byers Research mount. Yes, a 22" worm-wheel. I have seen
and used much smaller Byers mounts at costs of over $50,000 US. We did
a bit of planetary imaging under the steady South Florida skies. His facility
looks like a small star party with many scopes running- absent observers.
Most are on high-end mounts, including several Paramounts. We discussed
CCD imaging techniques and compared CCD images. Here, one can compare
SCT's, Mak's, and refractors on good mounts and good-excellent seeing.

The Paramount (at close to $10,000 US) uses stepper motors for up to 2
degrees per second and a cogged belt drive for the worms which are spring
loaded on rails to remove lash. Classic observatory mounts often do not use
spring loading, however, I'm seeing this on more and more recent mid to high-
end amateur mounts. Many of you know the LX-200 uses a spring loaded
worm carriage. The paramount is designed for permanent mounting.

So, after having personal access to all this great equipment, I returned home
to my tweaked and slightly modified 12" LX-200. Those that are new to this
list can find details to various mods and tweaks on Doc G's web site and
Ed Stewart's Topical Archives. I must say I was not disappointed with the
LX-200 performance. Of course, the LX-200 isn't a Paramount just as a
Paramount isn't a professional observatory mount, however, if one avoids
bumping the scope or mount (even lightly), the LX-200 works amazingly
well. Collimation of my 12" was dead-on (it usually is) and the smart drive
programmed months ago under good seeing was working very well. So well
that I decided to take a 10 minute guided (3 second corrections) and unguided
images to see how well the mount tracked. Both unbinned CCD images using
9 micron pixels were virtually identical at 2.5 arc-second FWHM (Full Width
Half Maximum) stellar in both x and y axis.

Many astrophotographers insist on constant guiding and question the notion
of leaving the scope for several minutes to relax while manually guiding.
However, I have found that under good seeing, a well aligned mount and
programmed PEC will allow several minutes of no guiding corrections. I
must say that under 1-2 arc-second seeing, constant guiding of a small
amateur mount produces a bit tighter stars, but not much so.

I believe serious observing and most astophotography on mass produced
amateur mounts will benefit from excellent polar alignment and excellent
PEC programming. Drift alignment is one of the best methods if not the
best method to achieve excellent polar alignment. Highly recommended.




--
Michael Hart
Husen Observatory

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