How cheap can I get

[Robfal]

I've now got a decent mount (EQ6) so guiding is now an option. My current setup is Startravel 120 on a EQ6 pro with a HX516 camera. I also have a LPI and use Astroart 4.

ideally I would get an ED80 to image through and use the ST120 as a guide scope. However SWMBO would NOT be happy if I bought one just now (already spent over £800 recently) so my question is:- Just how cheap a guide scope can I get away with? I know its not brilliant however I would try to use the LPI initially (bright stars only).

Here are a couple on ebay

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ih=007&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=170116438876&rd=1&rd=1

A Jessops R400- 80 80mm refractor FL 400

Or

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&ih=016&sspagename=STRK%3AMEWA%3AIT&viewitem=&item=260121947231&rd=1&rd=1

a Sebens 60mm refractor. A know Sebens aren't particular well thought of hence the title of the post

By the way, does anyone have experiance of guiding in AA4 (will post this in a separate thread). How do I control 2 cameras. Launch 2 copies of AA4?

Cheers

Rob

[barkis]

The guidescope does not have to be of a high quality. All you need is a fairly bright star, so a cheapy will do you. Are you goung to autoguide, or guide manually. Manual guiding will require your guider focal length, to be about twice that of the imaging scope.

There is probably a better suggestion to follow from someone doing exactly what you want to do.

Ron.

[GordonCopestake]

Vixen do a 70mm f10 refractor designed specifically for guiding. Ian King used to sell them for £50, but apparently not any more. Have a hunt around on ebay and the likes or throw up a wanted advert. Something like an ST80 would work well too

[Kaptain Klevtsov]

Be aware that the Jessops el-cheapo 'scopes have 1" eyepieces so you might struggle to get the guide camera to fit.

I use one of these

http://cgi.ebay.co.uk/SUNAGOR-500mm-TELEPHOTO-LENS-with-T2-Mount-for-PRAKTICA_W0QQitemZ150125216755QQihZ005QQcategoryZ707QQrdZ1QQcmdZViewItem

which I bought as a camera lens when I was a lad. I made some guide rings for it out of a pipe offcut and some screws.

Captain Chaos

[centroid]

I used to guide very effectively with an ST80, which even new are reasonably priced. Even trying to 'pick-up' a second-hand one is an option. When I bought an ED80, I sold my ST80, in 'mint' condition for £65.

70mm is probably as small an aperture that makes for a realistic guide-scope, but of course an 80mm is lot more helpful for providing a suitably bright star image to guide on.

However, even with the ED80, and a DSI as a guide camera, I sometimes struggle to find a guide star in some areas of the sky.

I do know that some people manage to use the LPI as a guide camera, and in one case, with a 70mm scope. However, I do know that quite often, he has to 'swing' the guide scope way off from the area containing the object to be imaged, in order to find a bright enough star.

If you are happy to do this, then you would 'get by' with the LPI. Its just that I'm a bit lazy, and having my guide scope aligned with the main scope, and the finder, I'm reluctant to move it away from the main FOV. Mainly because I sometimes image 'wide-field' with the ED80 (the guide scope), and guide with the 10" LX200GPS. So keeping everything aligned together, is convenient.

Dave

[Andrew*]

I'm trying to get rid of a 4.5" f8.8 tasco reflector OTA. You can take it for around £30 delivered if it's any use?

Andrew

[morayskies]

I normally wouldn't buy a 'scope from a camera shop but, several years ago, I couldn't resist buying a Jessops 80mm f5 refractor (R400-80) that was in a sale for just £27.  The tripod was useless, the finder equally rubbish and the focuser is a bit 'iffy',  The eyepieces were also not brilliant but, being 1.25", there was no problem as I had plenty of these.  When I first view the Moon though it, I was very disappointed as it suffered a lot of internal reflections.  Thus it was consigned to the back of the shed for a couple of years.

When it was finally 'refound' I decided to give it a second chance.  Having sourced some sticky back, black flock paper from Wilkinsons, I set about lining as many internal surfaces I could get to.  What a difference this made!  I have a number of 'scopes (namely a 6" SCT, 6" f8 Newtonian and 90mm f10 refractor) but this little Jessops 'scope is fun to use and, I think, the optics are not too shabby.  This image was taken on 8/12/15 with an unmodded Canon 450D on a guided CG5-GT mount.

I wouldn't advocate buying a 'scope from a camera shop but, on this occasion, I think I got a bargain.