St80 guidescope mounting help

[UKJay1971]

Hi - I am looking at a guidescope for an ED80 and am considering an ST80. First off, would this be a good match? If not, any alternatives?

 

Secondly, how do I attach it to my ED80? I haven't a clue about what mounts etc I'd need so any help / links will be greatly appreciated.

[Skipper Billy]

There are many ways - here are two suggestions - one is on top of the ED80 - the other is side by side - on the side by side its a bigger scope but the principle is the same.  I would avoid the adjustable mounting rings its a recipe for flexure - just bolt it down - as long as its 'pointing' roughly the same way as the main scope it will be just fine.

Let me know if you need more details.

https://www.flickr.com/photos/113316085@N05/albums/72157663274320360

https://sites.google.com/view/astroimaging/equipment

 

[steppenwolf]

This would be a very good and popular match.

Attach the ST80's tube rings to a dovetail bar and then bolt the bar down on top of the ED80's tube rings using 1/4" - 20 bolts.

You will find suitable threaded holes in the ED80 rings.

You will have to drill suitable matching holes in the ST80's dovetail bar.

[Starlight 1]

Well I was going to say this one.http://www.iankingimaging.com/show_product.php?id=1657

[Bizibilder]

I didn't bother with an "official" dovetail (too expensive!) - simply used a strip of 6mm x 50mm aluminium bar about 300mm long drilled as required.  Bolts between the ED80 tube rings (on top) and then position the ST80 rings as required.  It can also have other holes drilled to hold cable clips, camera leads etc.  

[graemlourens]

Hi Jay.

I can highly recommend that combination. This is what i have running in my observatory for 2 years now and guiding is never an issue.

It is important though that the connection etween the ED80 & the ST80 is rock solid. I asked FirstLightOptics (Sponsor of this Forum) what i need to connect the both, and they put together my Shopping-List that was required. All was perfect and its extremely solid without flexure (what would cause you headache while guiding as the guidescope would move differently relative to the ED80)

I would recommend to drop them a line asking them for the exact components you need (i can't find the email right now with all that i bought).

They recommended me a combination of a Dovetail bar, and 2 of these: https://www.firstlightoptics.com/adm-vixen-type-v-series/adm_vdpa_adaptor.html

Kind regards, Graem

[UKJay1971]

Thanks everyone - I'll email FLO later 

[Grierson]

1 hour ago, UKJay1971 said:

Hi - I am looking at a guidescope for an ED80 and am considering an ST80. First off, would this be a good match? If not, .......

You could of course consider a 'finder guider'. Less weight and no flexture. - John

[alacant]

Hi. Do you need such a big guidescope I wonder. How about a smaller -and lighter- 60mm model? I got one from AliExpress and mounted it side by side. I've tested guiding up to 1200mm using a zwo120 under PHD2. Here it is alongside my 80mm. HTH.

 

[laser_jock99]

2 hours ago, Bizibilder said:

I didn't bother with an "official" dovetail (too expensive!) - simply used a strip of 6mm x 50mm aluminium bar about 300mm long drilled as required.  Bolts between the ED80 tube rings (on top) and then position the ST80 rings as required.  It can also have other holes drilled to hold cable clips, camera leads etc.  

Agreed- homemade is the way to go. Adjustable guidescope rings are unnescessary these days, since guide camera CCDs are more sensitive than they used to be and aquiring a good guide star should not be an issue.

Guide scope mounted on a DIY 'top bar'.

[Ant-33]

I agree with others - it's a good choice. I use it with a 0.5x focal reducer to give me a wider choice of stars for guiding, and it works well. I use one of these:

and attach it thus:

This means I can slide the guidescope up and down to get the balance right. Works a treat.

Cheers. Tony

 

[UKJay1971]

Thanks for all the advice - FLO on the case as ever and scope plus bits and pieces on the way (arriving tomorrow). Going for the homemade aluminium box tube solution as it was by far the cheapest (less than a fiver for a suitable off-cut on eBay). Will let you know how I get on and, if we ever see clear skies again, how it guides

[spartan2007]

this is my mounting on my c925 hd Rock solid with th st80

[MattJenko]

I have used both a finder guider and an ST80 bolted to my ED80 and prefer the ST80 to be honest. Not really had many problems with the findeguider, but the ST80 setup just felt better and I am sure the final stars in my images were better. I simply took the original dovetail from the ED80 and put on top and put a longer dovetail underneath and then clamped the rings on to the top:

 

 

[spillage]

looking at these photos puts me to shame. I just used on old bit of fencing angle iron. Used by grinder to remove one edge and ending up with a flat iron bar and attacked that with my drill. Maybe I need to hammerite it to make it look more pleasing to the eye...some day.

[UKJay1971]

I have some ali shelving strips left - that is looking like a likely candidate

[UKJay1971]

Thanks everyone - £3 of aluminium did the trick