Hi Mike
that looks very good
Question about PST mod: keeping collimator lens at -200mm during focussing
-
swisswalter
- Way More Fun to Share It!!
- Posts: 17948
- Joined: Thu Feb 06, 2014 4:28 am
- Location: Switzerland
- Been thanked: 1 time
- Contact:
Re: Question about PST mod: keeping collimator lens at -200mm during focussing
Only stardust in the wind, some fine and some less fine scopes, filters and adapters as well. Switzerland 47 N, 9 E, in the heart of EUROPE 
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
from 7 am - 7 pm http://www.nanosys.ch
from 7.01 pm - 6.59 am http://www.wastronomiko.com some times vice versa
-
Solarhound
- Ohhhhhh My!
- Posts: 132
- Joined: Sun Jul 28, 2013 4:51 pm
Re: Question about PST mod: keeping collimator lens at -200mm during focussing
It was late when I posted the image last night and I didn't include an explanation . My first configuration used 2" extensions in place of the focuser . The mod was functional this way but not optimum and the sweet spot was difficult to deal with when the etalon was moving with the focuser . In my opinion for best results the etalon needs to be fixed at the 200mm location . I use this in a Celestron 102 Omni XLT with 3" removed from the tube , I lock the original focuser extended 1" and this places the etalon at the magic 200mm . This is the same mod using a B1800 straight through BF .