#1  
Old 10-08-2019, 11:29 AM
Startrek (Martin)
Registered User

Startrek is offline
 
Join Date: Dec 2017
Location: Sydney
Posts: 1,346
Proposal - Orion 60mm guide scope

Orion 60mm guide scope with helical focuser- Proposal

Iíve been using an Orion 50mm guide scope with helical focuser and a ZWO ASI120MM guide camera for over a year now on both my 6Ē and 8Ē newts and works well
The only problem I have is after slewing Goto and finding my object ready for imaging ( using my finder scope as part of the procedure ) , I have to remove my 50mm finder scope and replace it with the guide scope then plug the guide camera in and start PHD2 etc
If I was to buy and fit the Orion 60mm guide scope on a dovetail bar along the centre axis of my main scope OTA tube rings ( they have provision for mounting ) then I donít have to touch a thing all night . I have my finder and my guider on board and can do anything , especially if I change targets and I need to use the finder again to find objects again ( this is rare as EQMOD is really accurate but I have that back up if I need it )
Also my image scale on the 50mm guide scope is currently 4.77 arc sec / pixel but with the new 60mm guide scope it would now be 3.22 arc sec / pixel , therefore the image scale ratio between the main Scope ( say my 8Ē f5 newt ) and guide scope would go from currently 5.4 times to now 3.6 times which would be better
Plus the 60mm has a wider field for greater selection of guide stars in PHD2
With the 60mm guide scope bolted piggyback along the centre axis of the main scope ( very close ) it may reduce any movement or flexure compared to the 50mm guide scope which sits in a little shoe bracket off to one side sticking out 120mm from the OTA
As far as additional weight goes , leaving the finder scope in place and adding the new proposed 60mm guide scope it only adds 900grams to the payload which is acceptable for my 6Ēf6 newt and HEQ5 and not a problem at all with my 8Ēf5 newt and EQ6-R mount
Appreciate any advice or thoughts on the above proposal as Iím getting a bit sick of swapping equipment on the scope during imaging sessions
Also addition cost not a problem for me
I not looking for alternatives to the above or re invent the wheel but to ask whether anyone finds any issues with doing the above both in a technical and practical sense

Thanks in advance !
Reply With Quote
  #2  
Old 10-08-2019, 02:27 PM
xelasnave's Avatar
xelasnave
Gravity does not Suck

xelasnave is offline
 
Join Date: Mar 2005
Location: Tabulam
Posts: 12,848
https://www.google.com/url?sa=t&sour...wawQDG907uU5YA

I use one of these on my 80 mn.
Alex
Reply With Quote
  #3  
Old 10-08-2019, 03:09 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 9,227
Been using a Tak 7x50 finder converted with a helical focuser riding on top centre line in adjustable rings for years. I use a regular finder for alignment of the mount (or use the guide cam as an electronic finder) then remove the offset regular finder to remove asymmetric yaw and imbalance.

Use a Lodestar, so absolutely zero issues finding a guide star ever. Been using the guidescope with Lodestar much more frequently lately as a finder, not even bothering to mount the regular finder.
Attached Thumbnails
Click for full-size image (7906EF5F-BA6E-42A9-80C0-000DFF0DAC2B.jpeg)
149.3 KB17 views
Reply With Quote
  #4  
Old 10-08-2019, 10:39 PM
RyanJones
Registered User

RyanJones is offline
 
Join Date: Jun 2018
Location: Melbourne,Australia
Posts: 743
Hi Martin. I have one of these http://www.astroanarchy.com.au/teles...er_80x400.html
On a dovetail on top of my 8Ē f/4 Newt mounted on a HEQ5 Pro and it handles it perfectly. At 400mm with 80mm apature, it is incredibly easy to find good guide stars. $99 is an absolute bargain, so much so Iíve bought 2. One for my Newt and the other for my SCTs so I donít have to swap them over when changing scopes. They are a rack and pinion focuser which I find easy to use and easy to adjust without disturbing the guidescope. They have a pretty decent dew shield built in to the front which rarely fogs up too. Personally I feel itís a great option for guiding.
Attached Thumbnails
Click for full-size image (D534F355-4E1F-40C7-9C6B-9C0AD628CCCE.jpg)
201.7 KB24 views
Reply With Quote
  #5  
Old 11-08-2019, 08:50 AM
Startrek (Martin)
Registered User

Startrek is offline
 
Join Date: Dec 2017
Location: Sydney
Posts: 1,346
Thanks all for your advice !
Cheers
Reply With Quote
  #6  
Old 11-08-2019, 02:29 PM
peeb61's Avatar
peeb61 (Paul)
Always looking up

peeb61 is offline
 
Join Date: Jan 2007
Location: Wollongong
Posts: 678
Quote:
Originally Posted by RyanJones View Post
Hi Martin. I have one of these http://www.astroanarchy.com.au/teles...er_80x400.html
On a dovetail on top of my 8” f/4 Newt mounted on a HEQ5 Pro and it handles it perfectly. At 400mm with 80mm apature, it is incredibly easy to find good guide stars. $99 is an absolute bargain, so much so I’ve bought 2. One for my Newt and the other for my SCTs so I don’t have to swap them over when changing scopes. They are a rack and pinion focuser which I find easy to use and easy to adjust without disturbing the guidescope. They have a pretty decent dew shield built in to the front which rarely fogs up too. Personally I feel it’s a great option for guiding.
This looks like a doer! Thanks Ryan.

Did you need an extension tube to bring your guide camera to focus?

Paul

Last edited by peeb61; 11-08-2019 at 03:23 PM.
Reply With Quote
  #7  
Old 11-08-2019, 08:20 PM
RyanJones
Registered User

RyanJones is offline
 
Join Date: Jun 2018
Location: Melbourne,Australia
Posts: 743
Quote:
Originally Posted by peeb61 View Post
This looks like a doer! Thanks Ryan.

Did you need an extension tube to bring your guide camera to focus?

Paul
In my particular setup, Iím using a 1.25 diagonal which probably isnít the suggested way to use it but it works well for me and keeps my wiring over one side of the OTA. If I didnít use the diagonal then Iíd have to use an extension yes. Astroanarchy sell those too.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 07:09 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
SkyWatcher Australia
Advertisement
NexDome Observatories
Advertisement
Lunatico Astronomical
Advertisement
Bintel
Advertisement
Celestron Australia
Advertisement
OzScopes Authorised Dealer
Advertisement
Meade Australia
Advertisement
Astronomy and Electronics Centre
Advertisement