What are these dials and how can I actually utilize them?

[liechtenstein]

Hello everyone! I've got a question for my Celestron Powerseeker Equatorial. I believe they are called the RA and Dec, but I have no idea how to use them.

Image 1: http://i.imgur.com/3QjTs65.jpg

Image 2: http://i.imgur.com/dL7ooFW.jpg

Sorry if this is a sorta confusing way to ask.

[RLWP]

I know it's a different telespoce, even manufacturer, however the descriptions on pages 12 and 13 of this are pretty good: http://geogdata.csun.edu/~voltaire/classics/fullerscopes/BCFcatalogue_1985.pdf

Richard

[Kriss Craik]

Hi, I just recently watched a you tube clip on this and in short they are handy for getting your scope pointing in the vicinity of your target but lack the ability to get it Bob on. Think the clip was called "how to use setting circles on a small scope"

[damnut]

Once you have the scope aligned & sett latitude you can use the setting circles to dial in an objects ra and dec co-ordinates. Whilst not completely accurate and sometimes they are a pain to use, they can give a useful approximation for where you need to look.

[ronin]

The RA and Dec circle are fine but understanding them takes some getting used to.

The RA ones are related to time, and that is Local Time not what the clock says (necessarily). So it all gets somewhat convoluted to explain - consider that RA and Dec are fixed positions in the sky, but these fixed positions "move". It comes up on here at regular intervals.

I only got the idea of it after using a scope (two or three time) that had RA and Dec drives on it and a readout of the position that the scope was pointing at. Eventually it sank in. The problem is that I now have a way of understanding it, but my explanation to you may be gibberish as far as you are concerned :eek: . Almost certainly gibberish :grin: .

[Moon-Watcher]

I know it's a different telespoce, even manufacturer, however the descriptions on pages 12 and 13 of this are pretty good: http://geogdata.csun.edu/~voltaire/classics/fullerscopes/BCFcatalogue_1985.pdf

Richard

Excellent link.  I like their motto:  "With 200 years behind us - we're light years ahead".

Poetry...

Cheers,

Mark

[liechtenstein]

Thank you for the replies! I'll see what I can do (if the weather ever clears up). By the way, just one follow up question: what do the two sets of numbers on the RA thing mean? Thanks

[RLWP]

Thank you for the replies! I'll see what I can do (if the weather ever clears up). By the way, just one follow up question: what do the two sets of numbers on the RA thing mean? Thanks

0-24 hours, and 24-0 hours

Richard

[Scott]

Thank you for the replies! I'll see what I can do (if the weather ever clears up). By the way, just one follow up question: what do the two sets of numbers on the RA thing mean? Thanks

one for northern hemisphere and the other, the southern hemisphere

[skfboiler]

Here is a link to Astro-Tom's website on the subject of setting circles.  I think this will clear things for you.

http://www.astro-tom.com/telescopes/setting_circles.htm

[Wilhelmus]

Hi, you should look at this: 

[ronin]

How to use setting circles on a small telescope (and why they don't work)

Sounds odd, it implies that either the scope size is relevant, point a big scope at the RA+Dec of M42 and you see the nebula, point a small scope and the field is blank - makes imaging impossible, or that RA and Dec don't work - which will come as a bit of a surprise to astronomers and quite a few observatories, not to mention all the planetarium software that has just been defined as incorrect, there goes Stellarium.

Also how does the person show you how to use something that they say does not work before you have even looked at the video? Thoughts being you cannot be shown how to use them because they do not work. So showing them working is not possible.