Quote:
Originally Posted by syousef
I'm finding a digital inclinometer ($40) and manual azimuth setting circle plus a laptop do me fine. I usually get my object in or very near using a 42mm or 50mm 2" eyepiece. The azimtuth circle is a pain in the neck to print, but it can be done for the price of a few sheets of a4, a little printer ink and some laminate. I did end up cutting a small wedge out of the top circle on my dob base to accomodate though. I want some more regidity when I turn the azimuth circle during alignment, so 'm going to replace my circle with a laminate sheet I picked up from bunnings for $10.50.
Here's someone who's done it more neatly:
http://www.homebuiltastronomy.com/Ma...ingCircles.htm
I also have wheels on my base. Setup is a 1 star alignment. Total time to set up is about 5 mins from when I start carting my scope to the backyard.
I'm starting to work my way through the Messier list. Finding objects for the first time it takes me no time to be absolutely sure what I'm looking at. (I've had manual circles before on my smaller dobs but never locking wheels. I just bought a 12" and decided to do it properly).
Here is my alignment procedure.
1. Look up alt/az of alignment star
2. Plonk telescope down with azimuth roughly right and point at star (assisted by zero power finder, RACI)
3. Adjust telescope base to match az roughly and lock wheels
4. Fine tune by moving azimuth circle around and lock it down (my system uses velcro on the rim of the bottom ring to stick the laminated setting circle down in place)
5. Check and verify azimuth reading is correct.
6. Turn on inclinometer and point at alignment star. Zero inclinometer
7. Move telescope to negative altitude of star. Re-zero inclinometer
8. Move telescope back to star and verify inclinometer reading is correct.
This system is not accurate enough for extremely faint objects. I do sometimes have to scan a little. But not very much. Perfect for brighter messier objects. |
Hi syousef,
Its a very good suggestion, however I've been down this road before, and built a system exactly like you describe. However I really got jack of it after a while and found it to be a fiddly and unstable system. I had a similar problem as you with faint objects and it leaves you wondering if you just can't see the object, or if you aren't pointing in the right place.
It is a great way to get get pointing on a limited budget and I did fine it very worthwhile, I just wouldn't go back there again, I'd just get and argo navis.
Cheers,
Dave.