Re-positioning polarscope reticule

The base for all our tutorials, be it how to polar align or master astro imaging

Moderators: hawk_eye1975, budgetastro, martin_h


TUTORIALS SECTION

This section is only for the posting of actual tutorials, either single post or multiple, to ask questions or comment on a tutorial, please use the TUTORIAL DISCUSSIONS section where you will find a topic titled for each topic posted here, it just helps stop the topics becoming convoluted and lets the tutorials flow properly. If you post a tutorial, please also post a topic into TUTORIAL DISCUSSIONS with the same title.

Thanks.

Re-positioning polarscope reticule

Postby worcspaul » Wed Sep 28, 2011 8:44 am

When I first got my EQ5 earlier this year I noticed the position of the polaris indicator in the reticule was such that for it to be at the correct position for polaris transit the counterweight bar would have to be vertically UP. Whilst fitting replacing the adjusting grub screws with thumbscrews (see Polarscope Reticule centering and mods ) I thought I'd take the opportunity to re-position the reticule. This work is probably best done on a clear flat surface with the mount removed from its tripod and counterweight bar removed:

  • Unscrew and completely remove the lens from the rear of the polarscope
  • Holding a soft (microfibre for preference) cloth over the rear of the polarscope, loosen the three grubscrews and then carefully tilt the mount back so the reticule drops into the cloth.
  • Place the reticule on a clean sheet if paper and put a marker on the metal ring to indicate where the polaris circle is. I used a pointer cut from a sticky label. A spot of tippex (dries quicker than paint) would probably suffice :

Image

(This is to make it easier to position the reticule when placed back in the polarscope)

  • Make sure the mount is in the HOME position
  • Taking care not to drop the reticule or get fingerprints on it (been there, done that :sad: ), tilt the mount forward and replace the reticule in the polarscope with the marker at the top.
  • Re-insert the three grubscrews and slowly adjust each one a half turn at a time until the reticule is just held by them
  • If the marker is n't quite at the top, loosen the grub screws a fraction and use a cocktail stick or similar to rotate the reticule (there are a couple of slots in the inner ring of the reticule.
  • Your polarscope reticule should now be in the correct position:

Image

In this image you'll see the three grubscrews have been replace by M3x10 thumbscrews which make life a LOT easier!

  • Finally, replace the lens (fitting an O-ring if you choose to do so, following Dion's tutorial) and screw back in until at the desired focus point


Hi, you are viewing as a guest, You can only see this first post in this topic. if you sign up you get access to other goodies you can't even see as a guest, including video tutorials on imaging and processing, scope modifications and even member discounts on gear!

So, give us a try, what have you got to lose! Oh, and if you stay, when you reach 50 posts you get access to MORE goodies! What are you waiting for!

User avatar
worcspaul
Planetary Nebula
 
Posts: 966
Joined: Sun Apr 03, 2011 9:03 am
Location: Worcestershire

Re: Re-positioning polarscope reticule

Postby worcspaul » Thu Sep 29, 2011 7:36 am

User avatar
worcspaul
Planetary Nebula
 
Posts: 966
Joined: Sun Apr 03, 2011 9:03 am
Location: Worcestershire

Re: Re-positioning polarscope reticule

Postby guyroch » Mon Oct 17, 2011 1:30 pm

You do not have the required permissions to view the files attached to this post.
User avatar
guyroch
Main Sequence
 
Posts: 263
Joined: Thu Dec 02, 2010 7:12 pm

Re-positioning polarscope reticule

Postby Shorty73 » Mon Oct 17, 2011 4:45 pm

Shorty73
Protostar
 
Posts: 53
Joined: Mon Feb 21, 2011 11:51 pm
Location: Essex

Re: Re-positioning polarscope reticule

Postby worcspaul » Mon Oct 17, 2011 10:30 pm

User avatar
worcspaul
Planetary Nebula
 
Posts: 966
Joined: Sun Apr 03, 2011 9:03 am
Location: Worcestershire

Re: Re-positioning polarscope reticule

Postby worcspaul » Tue Oct 18, 2011 9:09 am

User avatar
worcspaul
Planetary Nebula
 
Posts: 966
Joined: Sun Apr 03, 2011 9:03 am
Location: Worcestershire

Re: Re-positioning polarscope reticule

Postby themos » Fri Oct 21, 2011 12:23 pm

themos
Nebula
 
Posts: 3
Joined: Wed Feb 02, 2011 12:12 pm

Re: Re-positioning polarscope reticule

Postby worcspaul » Fri Oct 21, 2011 3:28 pm

User avatar
worcspaul
Planetary Nebula
 
Posts: 966
Joined: Sun Apr 03, 2011 9:03 am
Location: Worcestershire


Return to TUTORIALS

Who is online

Users browsing this forum: No registered users and 1 guest