ICEINSPACE
Most Read Articles
Moon Phase
CURRENT MOON Waxing Crescent
32.5%
The Sun Now
Time Zones
Sydney*
4:05 am
Perth
1:05 am
Auckland*
6:05 am
New York
12:05 pm
Paris
6:05 pm
GMT
5:05 pm




Go Back   IceInSpace > Equipment > ATM and DIY Projects

Reply
 
Thread Tools Rating: Thread Rating: 2 votes, 5.00 average.
  #81  
Old 09-11-2018, 09:24 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Final cassegrain collimation tonight looks good.



Done with a ZWO ASI 120MM. THis time on the mount so it was very easy to recenter after tweaking the secondary tilt.
Attached Thumbnails
Click for full-size image (CN-212-834.jpg)
197.4 KB29 views
Click for full-size image (CN-212-835.jpg)
189.6 KB32 views
Click for full-size image (CN-212-831.jpg)
199.0 KB27 views
Reply With Quote
  #82  
Old 10-11-2018, 09:17 AM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 8,428
Kinda looks like a telescope again
Reply With Quote
  #83  
Old 10-11-2018, 10:31 AM
Kunama
.

Kunama is offline
 
Join Date: Sep 2012
Posts: 3,515
Great work on the collimation Marc. Looking forward to the images to come.
Reply With Quote
  #84  
Old 10-11-2018, 04:26 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Quote:
Originally Posted by LewisM View Post
Kinda looks like a telescope again
I knew frankenstein always had it in him, under all that rust, dints and cr4p it was a diamond in the rough.

Quote:
Originally Posted by Kunama View Post
Great work on the collimation Marc. Looking forward to the images to come.
I received all the collimation kits and adapter this morning in the mail so I will revisit for sure. The scope is cooling outside as we speak, everything is set up for a night of imaging or two, as sunday is looking good too..
Attached Thumbnails
Click for full-size image (CN-212-840.jpg)
198.6 KB27 views
Click for full-size image (CN-212-842.jpg)
199.5 KB21 views

Last edited by multiweb; 10-11-2018 at 06:30 PM.
Reply With Quote
  #85  
Old 11-11-2018, 12:55 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Tonight's efforts.

NGC104 8x180s
NGC2070 29x120s

Need to still fix collimation for stars. I can do that tomorrow as I've received all the collimations kits this morning. Field looks sharp and flat though with no noticable curvature or flaring corner to corner.
Attached Thumbnails
Click for full-size image (NGC104_L_CN-212_sf.jpg)
198.7 KB40 views
Click for full-size image (NGC104_L_CN-212_HD_crop_sf.jpg)
196.8 KB40 views
Click for full-size image (NGC2070_L_CN-212_sf.jpg)
198.6 KB43 views
Reply With Quote
  #86  
Old 11-11-2018, 04:15 PM
Dennis
Dazzled by the Cosmos.

Dennis is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 10,641
Quote:
Originally Posted by multiweb View Post
Tonight's efforts.

NGC104 8x180s
NGC2070 29x120s

Need to still fix collimation for stars. I can do that tomorrow as I've received all the collimations kits this morning. Field looks sharp and flat though with no noticable curvature or flaring corner to corner.
Yes Marc - they look very good from edge-to-edge, very nice indeed.

Cheers

Dennis
Reply With Quote
  #87  
Old 11-11-2018, 07:33 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Quote:
Originally Posted by Dennis View Post
Yes Marc - they look very good from edge-to-edge, very nice indeed.

Cheers

Dennis
Looks a lot better than the mewlon 210 because it's a classical cassegrain and better corrected. It was fairly easy to collimate accurately today. The newtonian side I did struggle. Got it in the end but it was pretty hard.
Reply With Quote
  #88  
Old 11-11-2018, 08:14 PM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 3,931
Looks like a great project Marc. Can't wait to see some images.

ps - no sign of Indian Mynas on those antennas....
Reply With Quote
  #89  
Old 12-11-2018, 06:42 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Quote:
Originally Posted by peter_4059 View Post
Looks like a great project Marc. Can't wait to see some images.

ps - no sign of Indian Mynas on those antennas....
I've had one dropping on the white tube already. No respect...
Reply With Quote
  #90  
Old 12-11-2018, 07:05 AM
RickS's Avatar
RickS (Rick)
PI cult recruiter

RickS is offline
 
Join Date: Apr 2010
Location: Brisbane
Posts: 10,306
Test images look good, Marc!
Reply With Quote
  #91  
Old 12-11-2018, 11:34 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Quote:
Originally Posted by RickS View Post
Test images look good, Marc!
Getting very close now.
Reply With Quote
  #92  
Old 12-11-2018, 01:46 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 8,428
Quote:
Originally Posted by multiweb View Post
I've had one dropping on the white tube already. No respect...
White?! White?! It’s not bloody white. I wish it were white... bloody ochre with blue tint...

Oh I had fun with that tube... might send Arief a “Pain and Suffering” claim (joking...kinda)
Reply With Quote
  #93  
Old 12-11-2018, 07:01 PM
Dennis
Dazzled by the Cosmos.

Dennis is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 10,641
Hi Marc

I don't know where I obtained this "Collimation Guide" but here it is, if it can be of any use for the CN-212.

Cheers

Dennis

EDIT:
http://www.alluna-optics.com/Downloa...on-English.pdf

https://gravitylens.files.wordpress....collimator.pdf

Last edited by Dennis; 12-11-2018 at 07:14 PM.
Reply With Quote
  #94  
Old 12-11-2018, 07:35 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Thanks a lot for posting all the links Dennis.

Quote:
Originally Posted by Dennis View Post
Hi Marc

I don't know where I obtained this "Collimation Guide" but here it is, if it can be of any use for the CN-212.

Cheers

Dennis

EDIT:
http://www.alluna-optics.com/Downloa...on-English.pdf

https://gravitylens.files.wordpress....collimator.pdf
Reply With Quote
  #95  
Old 12-11-2018, 07:35 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Some moonage waiting for dark tonight. SONY NEX-5 at the cassegrain focus in live view. With Mynas and all...





Video at cassegrain focus [F/12.4]



Video at newtonian focus [F/3.9]



Some stacked stills from the ASI120MM. All cassegrain. First one is at the newtonian focus.
Attached Thumbnails
Click for full-size image (moon_06.jpg)
199.3 KB16 views
Click for full-size image (moon_05.jpg)
194.8 KB12 views
Click for full-size image (moon_04.jpg)
193.5 KB15 views
Click for full-size image (moon_03.jpg)
196.2 KB13 views
Click for full-size image (moon_02.jpg)
198.3 KB15 views
Click for full-size image (moon_01.jpg)
199.7 KB13 views

Last edited by multiweb; Yesterday at 08:53 AM.
Reply With Quote
  #96  
Old Yesterday, 07:11 AM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Last night was great for testing. I had a couple of hours before clouds rolled in from the west and there was also a thin moon crescent to play with.

I had used the TAK scope the previous day to finish collimating the cassegrain focus. It's very close but still needs a tiny more tweaking which I'll do with the artificial star. I spent some time on the moon visually from 32mm to 24, 9, 6 and 4mm eyepiece. I could still easily snap to focus with the 4mm eyepiece and see some very nice sharp details. A lot more than with the C11. I took a couple of shots with my SONY NEX-5 and ZWO ASI 120MM.

Then I switched to the newtonian side which was a bit of a disaster. Visually the focus point snaps and the image is very sharp as well. The fov is huge. On closer inspection at higher magnification I can see very obvious astigmatism so the detective work is starting. I suspect something to do with the secondary as the primary is ok in cassegrain mode. There is an aluminum cylinder that encases the secondary glass to stop it from dewing up I assume. It was very tight so I've losen that. I think maybe it was pressing against the glass. The astigmatism can be compounded by the fact I still haven't got the newtonian side collimated correctly. But there is definitely some kind of stress in the glass there.

Here' s a couple of shots of the primary collimation push/pull system, centering and locking mechanism. It's well designed and very simple.
Attached Thumbnails
Click for full-size image (CN-212-851.jpg)
87.6 KB19 views
Click for full-size image (CN-212-850.jpg)
195.8 KB19 views
Reply With Quote
  #97  
Old Yesterday, 10:08 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Some good progress. Finally got everything collimated tonight including the newtonian side. The aluminum shroud for the secondary was stressing the glass and causing the distortion. Losening the screw that holds it did the trick. There is a very slight sign of astigmatism when very close to focus but nowhere near what it was. I don't think it will be and issue with the CCD given the image scale as it is so close to focus, might not even notice it. Will see when I do a full fov shot. I also tested the newtonian corrector. Seems to do a decent job. Will post before/after pics later on.

This is the diffraction rings for the newtonian focus IN/OUT. First part of the video with the SONY NEX-5 , second with the 120MM.

Reply With Quote
  #98  
Old Yesterday, 10:30 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 16,873
Here's the uncorrected (1st) and corrected field (2nd) with the SONY NEX-5.
Attached Thumbnails
Click for full-size image (CN-212_newtonian.jpg)
190.5 KB4 views
Click for full-size image (CN-212_newtonian_corrected.jpg)
195.6 KB4 views
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 03:05 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Advertisement
FLI Cameras and Imaging Accessories
Advertisement
Interest Free Finance
Advertisement
OzScopes Authorised Dealer
Advertisement
Lunatico Astronomical
Advertisement
NexDome Observatories
Advertisement
SkyWatcher WiFi Adaptor
Advertisement
SkyWatcher 2018 Catalogue
Advertisement
Atik Horizon
Advertisement
Bintel
Advertisement
Astronomy and Electronics Centre
Advertisement