Cold weather etalon performance

Use this section to discuss "standard" Baader/Coronado/ Lunt SolarView/ Daystar, etc… filters, cameras and scopes. No mods, just questions/ answers and reviews.
Post Reply
User avatar
jetstream
Ohhhhhh My!
Ohhhhhh My!
Posts: 54
Joined: Sun Mar 16, 2014 2:54 pm
Location: NW Ontario

Cold weather etalon performance

Post by jetstream » Sun Jan 10, 2016 4:00 pm

I'm still tossing around another Ha set up besides my Quark and have a few questions. My weather here is extreme- right now its -26c with a bright sunny sky and with some VG seeing around here.

Will a Lunt 60mm-internal air spaced etalon come on band from the factory? I'm at 1100ft with temps from +30c to -40c, summer to winter. What are the chances of both internal and external etalons working together at this cold temp? Will a pressure tuner (s) O ring hold its air? Would tilt tuning be better here?

One more...does etalon temp sensitivity go up with increasing etalon size ie the 60mm's internal vs the 80mm internal, Lunt that is. I can afford a scope, just not a mistake :shock:

Thanks,Gerry
Gerry
SW 120ED Pro,90mm Stellarvue
Baader Cool wedge, Quark Chrom

User avatar
MapleRidge
Way More Fun to Share It!!
Way More Fun to Share It!!
Posts: 5165
Joined: Fri Jan 13, 2012 11:58 pm
Location: Cambray, ON Canada

Re: Cold weather etalon performance

Post by MapleRidge » Sun Jan 10, 2016 4:21 pm

Hi Gerry...

I have operated my Lunt solar filters in the same temperature range that you describe with no issues. I have both presume (PT) and tilt tuned (TT) etalons in use. The LS80 in single stack mode (PT), double stacked with a LS75FHa front mount etalon (TT), and usually use the DSII module (PT) in a modded 150mm, f8 refractor.

The pressure tuning can be easily rest for you altitude by completely unscrewing the PT cap, remove it, and then thread it back on and tune. I do not move my equipment so I'm fixed at about 920 ft above sea-level, so this isn't too different form your elevation. I see a slight shift in tuning on the PT units if there is a considerable change in temps from one session to the next, but overall the units are very stable.

BTW...where are you located? I'm pretty sure that we know each other...Perceptor perhaps?
Brian
Last edited by MapleRidge on Sun Jan 10, 2016 4:29 pm, edited 1 time in total.
Brian Colville

Maple Ridge Observatory

Cambray, ON Canada

User avatar
jetstream
Ohhhhhh My!
Ohhhhhh My!
Posts: 54
Joined: Sun Mar 16, 2014 2:54 pm
Location: NW Ontario

Re: Cold weather etalon performance

Post by jetstream » Sun Jan 10, 2016 4:28 pm

Thanks Brian, I'm near Fort Frances, in between Thunder Bay and Winnipeg. We moved to a lake home that has some great skies, but there are temp extremes. So if I ordered a Lunt 60mm say, there is a VG chance it will work right out of the box? My Quark had to be tuned for my set up and temps...we'll see if it works today, unreal skies atm :)
Gerry
SW 120ED Pro,90mm Stellarvue
Baader Cool wedge, Quark Chrom

Post Reply

Who is online

Users browsing this forum: No registered users and 5 guests