Jump to content


Photo

Using my scopes setting circles

  • Please log in to reply
2 replies to this topic

#1 SimonC

SimonC

    Sputnik

  • -----
  • Posts: 30
  • Joined: 14 Jul 2009

Posted 27 August 2009 - 06:13 AM

Hoping someone can help me. I am quite new to astronomy and struggling with the setting circles.

I have purchased myself a HEQ5 mount and a WO MEGREZ 72 for Deep Sky AstroPhotography.

But am struggling to find objects. I have been following a tutorial I found on the internet which said Polar align your scope (Which I have by drift alignment), then find a star your know the coordinates of, centre in scope and set the setting circles to match it coordinates.

I have done the above and have no problem with Declination but when slewing the scope to Right Ascension the scope is pointing in a direction that is obviously not correct. I then have to manually swing back and forth in RA in the approx area I think the object is until I find it. Since I have such a small aperture on my scope it is not always possible with fainter objects.

Can anyone tell me what I am doing wrong or is there some issue with my mount.

Thanks for any help
Simon

#2 John Carruthers

John Carruthers

    Skiprat

  • *****
  • Posts: 3543
  • Joined: 02 Feb 2007
  • Loc: Kent, UK

Posted 27 August 2009 - 09:35 AM

Hi Simon, check which RA scale you are using, there may be 2, one for northern hemisphere and one for southern

Assuming you are in the northern hemisphere the scale should read higher as you slew the scope to the east.

Several things to check;
is your object correctly identified?
Where are you getting your coordinates from? a book, or a programme?
if it's a programme is it set for the correct date/time/position?
do you use daylight saving time?
any of those will throw you off to start with.
good luck, let us know how you get on.

#3 SimonC

SimonC

    Sputnik

  • -----
  • Posts: 30
  • Joined: 14 Jul 2009

Posted 29 August 2009 - 10:29 AM

Thanks John,

Had another go last night and I think I cracked the problem. It seems that the scale I need to use on the RA of my HEQ5 is the bottom not top. I know this is supposed to be for the southern hemisphere, but it seems to work for me. I also noticed that in my planetarium programme (Stellarium) I had not set it to use an equatorial mount. The combination of the two and I can now put an object with in my 25mm EP.

Thanks
Simon






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics