Re: ATM Mel's System

[cshaw@ghg.net (Charles W. Shaw)]

At 10:52 AM 5/27/97, Robert Duvall wrote:
>I just want to mention to all ATMer's that Chuck really is (er, was?) a big
>equatorial nut, based on his comments on the Astrophotography list. He must
>be really impressed to give such a report!

Robert-
Not to worry, I still am an equitorial platform nut!!!!  The ability to
have a Dob be able to track is probably the next best thing you can add to
your dob after a Telrad!

My enthusiasm for Mel's and Andy's systems stems from being relived of the
only real down side for platforms, that of needing to very accurately
physically polar align them in order to be able to do unguided
astrophotography.  BTW, fork and GEM's have the same problem!!!!!  Any
mount that depends on a real or virtual polar axis has this same problem.

However, you simply do NOT need this accuracy for visual work.  Even a
rough polar alignment (done in less than a minute) will suffice for most
visual work, and also for video (prime or afocal) work.  So the platform
option still remains a VERY rewarding and "cost/effort effective" option
for visual/video observing.  Add a bit more care in performing the
alignment and piggyback photography works well.  However, unguided prime
focus or EP Projection photography requires VERY good tracking, and that in
turn depends on very good polar alignment.   For portable operations this
takes away time from astrophotography operations (no matter what type mount
you have)....

Mel's and Andy's systems are a bit more complicated to build, and both
require the additional complexity and expense of either a laptop (Mel's) or
a microprocessor (Andy's), but thats the price you have to pay to get away
from the mechanical alignment required for forks, GEM's or platforms.....


>
>His astounding, glowing report here has convinced me to really take some
>time to finish mine. Just what I needed. Let's go for it!

No matter which way you decide to go (platform or Alt/Az) the ability to
track opens up a LOT of new activities for you!!!!   I want to see your
system finished and running Robert!!!!

Enjoy!!!

Chuck



Chuck Shaw
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