Re: [APML] Orion Min-EQ + EQ-1M

["Joseph O'Neil" <joneil@multiboard.com>]

>All of the low cost EQ mounts that I have seen need to be stripped down,
>cleaned, de-burred, re-greased, and touched up before they can be used.
>That being said, you can manage some piggyback guided photos with an
>EQ-4 that has been re-worked.

-snip-

         Go to http://www.astornomyboy.com - and read "regreasing the CG5 
(aka EQ5 ) mount".
         Also, not well covered there, is the fact the worm gear is held in 
place often by rubber O-rings, which introduces a heck of a lot of periodic 
error.  You will have to either replace this O-ring with better 
bushings/bearings, or make some thing up yourself to do so.

         To bakc up Georges earlier suggestion, Barn door (or scotch mount) 
drives are an amazingly low cost, low tech and very viable alternative for 
piggy back work.  You can eaisly use a 50mm lens on a barn door mount and 
get good results, and if you really bust your but and make an accurate barn 
door mount (that is, high quality hinge, exact measurements, everything 
square, etc), you can use lenses in the 85 to 135mm range easily.

         Polar alignment on a barn door mount can easily be done even with 
an old 6x30 finder.  Use the Kochab method of finding true polar north.

         About the only real imaging you can do with any of these low cost 
mounts is web cam imaging of the moon, and maybe some of the planets when 
you get into larger mounts/scopes.  For exmaple, with these Eq1 and Eq2 
mounts, and a simple RA motor drive, you can get some half decent web cam 
images of the moon.  read the current, June 2003 issue of Sky & Telescope 
article on planetary web cam imaging to get an idea.

         But for film use, or even mounting a largish digital camera on th 
eend of an eyepeice, naw, you'll driv eyourself nuts.  Go barn door, very 
litle to break down, you can motorize the sucker with a $5.00 motor form a 
surplus store, and a top of the lien barn door tracker, built with all 
brand new parts, will still cost you well under $100.

good luck
joe



http://www.oneilphoto.on.ca
http://www.multiboard.com/~joneil
Una salus victis, nullam sperare salutem


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