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Who's using manual RA and Dec circles?

Posted: Tue Jun 16, 2020 1:03 pm
by pakarinen
Curious how many folks here use manual RA and Dec circles.

I love alt-az push-to with Sky Safari on my phone, but sometimes I think I should chuck it all and go old school which was the way I learned things long ago...

Re: Who's using manual RA and Dec circles?

Posted: Tue Jun 16, 2020 4:54 pm
by Shabadoo
I often do. When the GOTO gives me fits, I move to setting circles. I found a good list of guide stars, and as long as I plan for the night, and am quick, it works well.

Re: Who's using manual RA and Dec circles?

Posted: Tue Jun 16, 2020 7:04 pm
by Lady Fraktor
If using my TAL mount I like to use the setting circles as they are large enough to read easily.

Re: Who's using manual RA and Dec circles?

Posted: Sat Aug 01, 2020 4:20 am
by konza
I recently got a Sky View Pro (non goto) with ra/dec circles for the simplicity of it. Yes, I have a goto but honestly most of the time I grab the Twilight1. No wires, batteries, or handbox. But honestly, my star hopping is atrocious! Although the SVP's circles are but 86mm diameter they are usable after a slight modification~~~ T-pins with the tips painted black and affixed so they actually overlap the circles a bit. They stand out over the scales and have much finer definition than the cast in arrows.

Re: Who's using manual RA and Dec circles?

Posted: Sat Aug 01, 2020 12:26 pm
by The Happy Parrot
Like you, I am not very good at star hopping so I made alt-az circles for my Z8 Dobson and they work fine but soon afterward I discovered digital inclinometers (http://www.wixey.com/anglegauge/) and they are much quicker and easier to use for alt. For azimuth the circle works OK but I often have to bend over to read it down by the base.

Most recently I adapted my Celestron StarSense Explorer plate solving phone app to my Z8 and the circles are obsolete. It's just much quicker and convenient.

Re: Who's using manual RA and Dec circles?

Posted: Sat Aug 01, 2020 1:25 pm
by KathyNS
Not so much on my GEMs, especially since they are goto. Their setting circles are close to useless.

But my wedged-fork-mounted grab-and-go C-90 has wonderful setting circles. Because the RA motor drives the RA setting circle along with the scope, I only have to set the circle once per session. It has a sidereal time index on the motor housing. I set sidereal time at the beginning of the session, and the RA circle is good for the rest of the night. I can easily read it to the nearest minute. The dec circle is good to the nearest 1/4 degree.

For setting sidereal time, I have an old travel alarm clock that never kept good time. It ran 4 minutes fast per day. Hello? Sidereal time!! I can set the clock to sidereal time at home and then use it to set the mount's setting circle in the field. :D

Re: Who's using manual RA and Dec circles?

Posted: Sat Aug 01, 2020 2:05 pm
by bobharmony
Wow - you are taking me back to my early days. I used the setting circles on my manual GEM that I mounted my department store refractor on back in the 60's. Thanks for the trip down memory lane. These days it is all AP all the time with platesolving and goto aiming.

Bob

Re: Who's using manual RA and Dec circles?

Posted: Sat Aug 01, 2020 3:56 pm
by SkyHiker
I put manual setting circles on my Dob, both Alt and Az. They work great. Calibration is done on a single star after leveling the base. One gotcha is that it relies on the optical axis coinciding with the OTA axis, otherwise you need a 2 star calibration which you can't do with a Dob. And that depends on whether the secondary has an offset or not. Anyway it works well enough.

I used my non-goto Losmandy G11S with its setting circles ghat are very good BTW. Here too though, if a refractor has a cone error, a one star calibration won't get you exactly to the target. Half the time it worked, the rest of the time I kept searching with my camera. I now added a goto kit and use EQMOD or Ekos for goto alignment. With AP there are so many problems already, not worth spending much time on alignment.

Re: Who's using manual RA and Dec circles?

Posted: Sun Sep 13, 2020 12:09 pm
by John Baars
I used to do that on my old orange fork-mounted C8. It worked!