Return to the Cloudy Nights Telescope Reviews home page


Telescope Specific Forums >> Meade ETX

Arthur Dent
Galactic Hitch-Hiker
*****

Reged: 10/23/08
Posts: 1177
Loc: South Yorkshire, UK
Re: is my LS dew heater correct?
      06/24/09 06:52 PM

Hi Pepper

It looks like you've got the dew heater around the wrong end as the guys have already said.

When there is lots of dew, the front glass element (the corrector lens) loses heat faster than the rest of the scope, so dew builds up on the corrector and if fogs up.

The dew heater is intended to raise the temperature just enough that the dew evaporates and doesn't condense on the corrector plate.

Dew shields (like that on my NexStar 6SE) have to have a notch cut in them if the mounting bracket (as in the ETX-LS) or the dovetail (in the case of my 6SE) protrudes out of the side of the scope where the corrector lens is.

On my ETX-105, the dew shield screws into the front of the corrector (where the metal lens cap screws in), so it isn't a problem with the ETX-105 (or the ETX-90 or ETX-125 for that matter).

Hope this helps

Art

--------------------
If I like it, the wife says that we can't afford it!
=======================================================

Meade ETX105 (a nice "Grab & Go" scope) & Celestron NexStar 6SE with Bob's Knobs.

Various EP's from 6mm to 26mm, Baader Hyperion 8-24mm Zoom, a 2x Barlow, 2" diagonal and 7Ah PowerTank.
MRF and Antares 8x50 RACI finder scope - both for the 6SE's OTA, whilst the ETX gets a plain RDF.

Canon EOS 400D DSLR (un-modded) and SPC900 webcam. Finally climbing the AP Learning Curve!

Post Extras Print Post   Remind Me!     Notify Moderator

Entire thread
Subject Posted by Posted on
* is my LS dew heater correct? pepper 06/24/09 02:01 PM
. * Re: is my LS dew heater correct? StarWars   06/24/09 03:05 PM
. * Re: is my LS dew heater correct? brianb11213   06/24/09 03:34 PM
. * Re: is my LS dew heater correct? Astroboy86   06/24/09 06:20 PM
. * Re: is my LS dew heater correct? Arthur Dent   06/24/09 06:52 PM
. * Re: is my LS dew heater correct? pepper   06/24/09 09:08 PM
. * Re: is my LS dew heater correct? Astroboy86   06/25/09 12:58 AM
. * Re: is my LS dew heater correct? Arthur Dent   06/25/09 10:32 AM
. * Re: is my LS dew heater correct? Astroboy86   06/25/09 10:57 PM
. * Re: is my LS dew heater correct? brianb11213   06/26/09 04:40 AM
. * Re: is my LS dew heater correct? Peter9   06/26/09 07:32 AM
. * Re: is my LS dew heater correct? Arthur Dent   06/26/09 06:47 PM
. * Re: is my LS dew heater correct? brianb11213   06/27/09 06:30 AM
. * Re: is my LS dew heater correct? pepper   06/25/09 10:47 PM
. * Re: is my LS dew heater correct? brianb11213   06/24/09 02:33 PM
. * Re: is my LS dew heater correct? Peter9   06/24/09 02:57 PM

Extra information
3 registered and 5 anonymous users are browsing this forum.

Moderator:  Shadowalker, oldsalt 



Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled

Rating:
Thread views: 594


Jump to

CN Forums Home



Cloudy Nights Sponsor: Astronomics