Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Combating dew | Secondary Mirror | Explore Scientific N208CF

  • Please log in to reply
4 replies to this topic

#1 Mlee880

Mlee880

    Lift Off

  • -----
  • topic starter
  • Posts: 8
  • Joined: 27 Jan 2019

Posted 06 August 2020 - 05:27 PM

I am trying to find a solution to the condensation that builds up on the secondary mirror of my newtonian. Attached are pictures of the secondary mirror stalk. The Kendrick heaters do not work on this style secondary. I will not wrap dew heater straps around the mirror as I don't believe that is a real solution, it would cause more problems than solutions. I don't want to use a hair dryer as I am trying to fully automate the session. I use a PrimaLuce Lab Eagle3 that I can power a dew heater from, and currently use one to heat my primary mirror and guidescope. I have tried building my own dew heaters from two 330 ohm resistors and nichrome wire. According to my calculations, the current draw should have been less than 3 amps on both of the contraptions I built, however the Eagle shows the current and wattage bouncing all over the place, going over the 3 amp limit allowed by the Eagle.

 

I am out of ideas and curious to hear about what others may be doing with this exact scope or similar secondary mirror styles.

 

Image: https://1drv.ms/u/s!...DbfA6Q?e=WT5655

 

Lee



#2 Migwan

Migwan

    Vanguard

  • *****
  • Posts: 2,073
  • Joined: 24 Jul 2017
  • Loc: Meeechigan

Posted 06 August 2020 - 06:04 PM

What gauge nichrome did you use?  And how long?


Edited by Migwan, 06 August 2020 - 06:04 PM.


#3 junomike

junomike

    Hubble

  • *****
  • Moderators
  • Posts: 19,590
  • Joined: 07 Sep 2009
  • Loc: Ontario

Posted 06 August 2020 - 06:36 PM

I went with R-Sky Dew Heaters (Newt Secondary) and it clears the fully Dew'd over Secondary withing 10 min.

 

These are Wrap around heaters but they work



#4 spereira

spereira

    Soyuz

  • *****
  • Moderators
  • Posts: 3,611
  • Joined: 21 Apr 2017
  • Loc: Bedford, NH

Posted 06 August 2020 - 08:05 PM

Moving to Reflectors ...

 

smp



#5 Guedovsky

Guedovsky

    Lift Off

  • -----
  • Posts: 22
  • Joined: 01 May 2020
  • Loc: Cascais, Portugal

Posted 07 August 2020 - 01:43 PM

i use wrap around by astroshop/omegon and they work great

Why don’t you want to use wrap around?




CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics