Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Thread: Dew Shield

  1. #1
    chryso's Avatar
    chryso is offline White Dwarf
    Points: 508, Level: 10
    Level completed: 16%, Points required for next Level: 42
    Overall activity: 0%
    Join Date
    Jan 2012
    Location
    Red Stick, Louisiana
    Posts
    44
    Points
    508
    Level
    10
    Thanks
    9
    Thanked 8x 6 Posts

    Default Dew Shield



    I am going to my first star party soon and I am concerned about dew forming on my telescope. After looking around they seem kind of expensive. Can anyone recommend a way to fashion my own dew shield?

  2. #2
    fogfire's Avatar
    fogfire is offline HYPER GIANT
    Points: 51,092, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!First 1000 Experience Points400+ Posts Achievement100+ Threads Achievement!
    Join Date
    Jun 2011
    Location
    Lynnwood WA, USA
    Posts
    3,200
    Points
    51,092
    Level
    100
    Thanks
    1,408
    Thanked 1,683x 1,047 Posts
    Blog Entries
    4

    Default

    What kind of scope?
    For 6-9.25" SCTs scopes you can get one with Velcro etc. for under $25. That said. You can go get something like a roll-up with sled or other stiff plastic and make one. Just needs to be stiff enough that it doesn't sag and tight enough it doesn't slip off
    Ken H. sharing the sky with my 9yr old daughter
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    ZEQ25GT - w/Meade 10" SN F4 1000MM "BIG Linda!" * w/Astro Tech AT65EDQ "Tiny Rosa"
    4SE & 6SE to be named *
    Meade Star Navigator 102 "Blue Bird" Daughter's
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Lynnwood Sky Guess
    Check out my most recent Blog "Ken's Personal Update - 4-2-2013"

  3. The Following User Says Thank You to fogfire For This Useful Post:

    ChuckWalters (03-14-2012)

  4. #3
    chryso's Avatar
    chryso is offline White Dwarf
    Points: 508, Level: 10
    Level completed: 16%, Points required for next Level: 42
    Overall activity: 0%
    Join Date
    Jan 2012
    Location
    Red Stick, Louisiana
    Posts
    44
    Points
    508
    Level
    10
    Thanks
    9
    Thanked 8x 6 Posts

    Default

    I have an ETX-125.

  5. #4
    ChuckWalters's Avatar
    ChuckWalters is offline HYPER GIANT
    Points: 29,801, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    50 Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!5 Threads Achievement!Got three Friends200+ Posts Achievement!
    Join Date
    Jan 2012
    Location
    Upstate New York
    Posts
    2,798
    Points
    29,801
    Level
    100
    Thanks
    2,189
    Thanked 1,026x 803 Posts
    Blog Entries
    4

    Default

    A foam exercise mat cut to shape works. The vinyl coating helps with the slippage factor. I once used the neoprene leg from my old fly fishing waders (boots started leaking). Worked well.
    CHUCK WALTERS SCOPES: Celestron 1100 XLT; EdgeHD 800; Exp. Sci. ED80 APO; AR102; Orion 10" f/4 Astrograph; XT8 LE; Astro Tech AT72ED Coronado SolarMax II 60 BF15 MOUNTS: Celestron CGEM DX; CG-5GT; NexStar 6/8SE CAMERAS: JTW Ice Cube 650D BCF; JTW Ultimate 1100D v3; IS DBK21AU618; DMK21AU04 ZWO ASI120MC; ASI120MM SOFTWARE: StarTools 1.3; PixInsight; RegiStax 6; PHD; BYEOS; APT 2.0; FireCapture 2.2

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


  6. #5
    KathyNS's Avatar
    KathyNS is offline Super Moderator
    Points: 173,224, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 44.0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!First 1000 Experience Points400+ Posts AchievementGot three Friends
    Awards:
    Reply Award
    Join Date
    Nov 2010
    Location
    Nova Scotia
    Posts
    25,178
    Points
    173,224
    Level
    100
    Thanks
    6,660
    Thanked 14,988x 9,544 Posts
    Blog Entries
    3

    Default

    Anything flexible and plastic-y will do. Don't use cardboard, as it will get soaked and soggy. I used a plastic report cover. Bend it into a tube, add a bit of duct tape, and violà!

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


    DSO AP:
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,LRGB filters; KWIQ/QHY5 guide
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    ; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome;
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    (pier);
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    .

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  7. #6
    TheBum's Avatar
    TheBum is offline Star Giants
    Points: 5,837, Level: 52
    Level completed: 44%, Points required for next Level: 113
    Overall activity: 0%
    Achievements:
    5 Threads Achievement!50 Posts Achievement!2 Posts Achievement20 Posts Achievement!5+ Referrals Achievement!
    Join Date
    Mar 2012
    Location
    McKinney, TX
    Posts
    127
    Points
    5,837
    Level
    52
    Thanks
    10
    Thanked 14x 14 Posts

    Default

    Wouldn't you want something that was somewhat absorbent so that the dew didn't run down the shield and onto the lens? I was wondering about using foam sheets from a craft store. They're pretty stiff but flexible enough to form around the tube.
    Alan
    Bushnell 675x4.5" Reflector

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    8SE Schmidt-Cassegrain


    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  8. #7
    KathyNS's Avatar
    KathyNS is offline Super Moderator
    Points: 173,224, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 44.0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!First 1000 Experience Points400+ Posts AchievementGot three Friends
    Awards:
    Reply Award
    Join Date
    Nov 2010
    Location
    Nova Scotia
    Posts
    25,178
    Points
    173,224
    Level
    100
    Thanks
    6,660
    Thanked 14,988x 9,544 Posts
    Blog Entries
    3

    Default

    The dew will form on the outer surface of the shield, where it won't affect the lens. If you make it absorbent, the weight is going to increase as it absorbs water and throw your balance off.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


    DSO AP:
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,LRGB filters; KWIQ/QHY5 guide
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    ; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome;
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    (pier);
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    .

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  9. #8
    TheBum's Avatar
    TheBum is offline Star Giants
    Points: 5,837, Level: 52
    Level completed: 44%, Points required for next Level: 113
    Overall activity: 0%
    Achievements:
    5 Threads Achievement!50 Posts Achievement!2 Posts Achievement20 Posts Achievement!5+ Referrals Achievement!
    Join Date
    Mar 2012
    Location
    McKinney, TX
    Posts
    127
    Points
    5,837
    Level
    52
    Thanks
    10
    Thanked 14x 14 Posts

    Default

    Quote Originally Posted by KeithBC View Post
    The dew will form on the outer surface of the shield, where it won't affect the lens. If you make it absorbent, the weight is going to increase as it absorbs water and throw your balance off.
    What keeps it from getting inside the shield? For example, if you have the scope pointed east at a 45 degree elevation, wouldn't dew form on the eastern inside surface, since it would essentially "jut out" ? Or does the hollow opening have aerodynamic properties that would prevent the dew from settling?
    Alan
    Bushnell 675x4.5" Reflector

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    8SE Schmidt-Cassegrain


    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

  10. #9
    fogfire's Avatar
    fogfire is offline HYPER GIANT
    Points: 51,092, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!First 1000 Experience Points400+ Posts Achievement100+ Threads Achievement!
    Join Date
    Jun 2011
    Location
    Lynnwood WA, USA
    Posts
    3,200
    Points
    51,092
    Level
    100
    Thanks
    1,408
    Thanked 1,683x 1,047 Posts
    Blog Entries
    4

    Default

    Quote Originally Posted by TheBum View Post
    What keeps it from getting inside the shield? For example, if you have the scope pointed east at a 45 degree elevation, wouldn't dew form on the eastern inside surface, since it would essentially "jut out" ? Or does the hollow opening have aerodynamic properties that would prevent the dew from settling?
    Shield really just slows the process, it depending on where you are and conditions it might not be enough. This winter I added heater strip to my scopes.
    And you are right the more towards the zenith the faster the process that will dew up the scope.

    I have one dew strip and on my 6" I sprang for combined dew heater shield.
    Ken H. sharing the sky with my 9yr old daughter
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    ZEQ25GT - w/Meade 10" SN F4 1000MM "BIG Linda!" * w/Astro Tech AT65EDQ "Tiny Rosa"
    4SE & 6SE to be named *
    Meade Star Navigator 102 "Blue Bird" Daughter's
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Lynnwood Sky Guess
    Check out my most recent Blog "Ken's Personal Update - 4-2-2013"

  11. #10
    KathyNS's Avatar
    KathyNS is offline Super Moderator
    Points: 173,224, Level: 100
    Level completed: 0%, Points required for next Level: 0
    Overall activity: 44.0%
    Achievements:
    200+ Posts Achievement!Ghost Achievement! Averaging 5+ posts a day!First 1000 Experience Points400+ Posts AchievementGot three Friends
    Awards:
    Reply Award
    Join Date
    Nov 2010
    Location
    Nova Scotia
    Posts
    25,178
    Points
    173,224
    Level
    100
    Thanks
    6,660
    Thanked 14,988x 9,544 Posts
    Blog Entries
    3

    Default

    Quote Originally Posted by TheBum View Post
    What keeps it from getting inside the shield? For example, if you have the scope pointed east at a 45 degree elevation, wouldn't dew form on the eastern inside surface, since it would essentially "jut out" ? Or does the hollow opening have aerodynamic properties that would prevent the dew from settling?
    Yes, you could get a little bit on the lower inside. Dew formation there will be slower than on fully exposed surfaces because it is partially enclosed. Being on the lower surface, it's not likely to wet the lens, since the lip of the OTA will stop it. If there is enough to actually wet the lens, you probably shouldn't be out there anyway!

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.


    DSO AP:
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    Newtonian Astrograph; ATIK 383L+; EFW2 filter wheel; Astrodon Ha,LRGB filters; KWIQ/QHY5 guide
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    ; Planetary AP: Celestron C-11; ZWO ASI120MC; Portable: Celestron C-8 on
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    pro; C-90 on wedge; 20x80 binos; Etc: Canon 350D; Various EPs, etc. Obs: 8' Exploradome;
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    (pier);
    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.
    .

    To view links or images in signatures your post count must be 5 or greater. You currently have 0 signatures.

 

 
Page 1 of 2 12 LastLast

Similar Threads

  1. Dew shield
    By J.Smet in forum Telescope Accessories Forum
    Replies: 13
    Last Post: 02-29-2012, 08:36 AM
  2. Eye shield
    By BMitchell in forum Telescope Accessories Forum
    Replies: 5
    Last Post: 07-04-2011, 04:42 PM
  3. Dew shield?
    By edr247 in forum Telescope Accessories Forum
    Replies: 7
    Last Post: 04-15-2011, 03:16 AM
  4. Dew Shield for SCT
    By dmoody in forum Amateur Astronomy Forum
    Replies: 10
    Last Post: 04-13-2004, 04:25 PM
  5. Dew Shield
    By Doink in forum Amateur Astronomy Forum
    Replies: 7
    Last Post: 02-26-2004, 07:05 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBulletin® Version 4.2.0
Powered by vBulletin®
All times are GMT. The time now is 09:59 PM.