#1  
Old 24-04-2013, 10:09 PM
Joshua Bunn's Avatar
Joshua Bunn (Joshua)
Registered User

Joshua Bunn is offline
 
Join Date: Oct 2011
Location: Albany, Western Australia
Posts: 1,459
Dew on ccd cover Glass

Hi,

I have an stl11000 and the cover glass continually dews over on the outside at the start of an imaging session even at -20. Bellow is a picture of what a downloaded image looks like.
This completely puts a stop to the night. Although one time i did pull the camera off and blow a hair drier in the camera and focuser, that fixed it but im not doing that every time. Ive just had it inside the house trying to dry the camera out as it probably picked up this moisture from being in an observatory ..... I need to get a dehumidifier.

The camera already has 2 heater strips on the ccd box to try and keep moisture off but they are not doing their job.

I understand that putting the camera on the back of the scope in humid conditions will only make the situation worse when the temperature drops at night.

I would like to hear from others who may have had this happen and what they did to fix it..... maybe sit by the camera for a day with the hair drier

thanks
Josh
Attached Thumbnails
Click for full-size image (Capture.jpg)
198.3 KB31 views
Reply With Quote
  #2  
Old 25-04-2013, 01:19 AM
Joshua Bunn's Avatar
Joshua Bunn (Joshua)
Registered User

Joshua Bunn is offline
 
Join Date: Oct 2011
Location: Albany, Western Australia
Posts: 1,459
OK, I see there are several options:

Purge the sealed area of moist air.
Use desiccant packs - which i did try.
Slowly cool the ccd.

Will keep looking.
Reply With Quote
  #3  
Old 25-04-2013, 02:21 PM
LewisM's Avatar
LewisM
Novichok test rabbit

LewisM is offline
 
Join Date: Aug 2012
Location: Somewhere in the cosmos...
Posts: 10,388
Would like to see some answers to this too Joshua. Mine has not done it - yet - and hope it WON'T.

I ALWAYS keep my focal reducer assembled to the camera. I think this tends to create somewhat of a closed system, keeping a stable air amount etc, and not introducing "new" air whenever I would say reassemble the FR to the CCD. I could be way off, but seems to work anyway.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 06:16 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
Bintel
Advertisement