ICEINSPACE
Most Read Articles
Moon Phase
CURRENT MOON Waxing Gibbous
63.6%
The Sun Now
Time Zones
Sydney*
12:27 pm
Perth
9:27 am
Auckland*
2:27 pm
New York
8:27 pm
Paris
2:27 am
GMT
1:27 am




Go Back   IceInSpace > Beginners Start Here > Beginners Equipment Discussions

Reply
 
Thread Tools Rate Thread
  #21  
Old 23-10-2018, 05:06 PM
astro744
Registered User

astro744 is offline
 
Join Date: Apr 2007
Posts: 746
Reason 1:
I cannot see the return beam spot on the end of the laser collimator because it sits 60mm up into the draw tube as viewed from inside the OTA. If I were able to insert the focuser further into the draw tube as I can do on my GSO focuser I could easily see the spot. Yes there are other collimators available but so are there other focusers.

Reason 2:
The Paracorr type 1 has a 60mm nosepiece. I can only insert 45mm and as a result cannot achieve focus. Again I have no problem with the GSO focuser.

I cannot fathom why a focuser design would provide a stop to prevent accessories being fully inserted other than to prevent items slipping in and hitting the mirror. I cannot think of a single accessory that is 2" diameter along its entire body and if there is one out there it would not be common enough to require this annoying safety feature.

Both of the reasons I mentioned are common applications that other focuser manufacturers have accommodated.
Reply With Quote
  #22  
Old 23-10-2018, 05:17 PM
raymo
Registered User

raymo is offline
 
Join Date: Sep 2011
Location: margaret river, western australia
Posts: 4,443
Fair enough; I did ask what was different about a Paracorr, and now I know.
cheers raymo
Reply With Quote
  #23  
Old 23-10-2018, 05:49 PM
astro744
Registered User

astro744 is offline
 
Join Date: Apr 2007
Posts: 746
Quote:
Originally Posted by raymo View Post
Fair enough; I did ask what was different about a Paracorr, and now I know.
cheers raymo
No worries, raymo. I just had a closer look at the collar that screws into the draw tube and I now know why the stop is there. It isn't because a stop was needed or intended as a safety feature but because extra thickness was needed to accommodate the male thread that goes into the draw tube. If it were possible to leave at 2" I.D. I'm sure it would have been done. My electronic vernier battery is flat so I couldn't measure how close to 2" it is but it does only need a minimal turn down on a lathe.

Anyway, I have digressed here although it is still relevant to comparing GSO with SW. There are many other factors to consider and the focuser is just one of them.

To the OP; whatever you choose, enjoy!
Reply With Quote
  #24  
Old 24-10-2018, 07:11 AM
Allan_L's Avatar
Allan_L (Allan)
Member > 10year club

Allan_L is offline
 
Join Date: Mar 2008
Location: Central Coast NSW
Posts: 2,989
Quote:
Originally Posted by raymo View Post
I can't fathom out for the life of me why any 2" accessory needs to enter the draw tube at all, the focal point is well outside the draw tube; certainly eyepieces, barlows and collimators don't.
The 2" adaptor allows accessories to slide in about 50mm, how much more do you need?
raymo
I am no techno expert Raymo, but from what I can tell, the whole point of the Paracorr is to get the eyepiece at a particular position hence the micro adjusting height (turntable) to use for different eyepieces. I would think that it needs to be fully seated to achieve this.

http://www.televue.com/pdf/literatur...structions.pdf
Attached Thumbnails
Click for full-size image (paracorr.jpg)
5.5 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 11:27 AM.

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