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Dew shield for C5, needed?

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#1 Anony


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Posted 26 October 2021 - 01:30 PM

I recently picked up a Starsense DX5, and am wondering if a dew shield would be helpful? I assume so...

but would the Celestron 6/8 fit? Or should I just make my own out of foam or something?


So far I've only been able to take it out once, and not so long, so haven't dewed up yet. Since it's a new scope, new scope rules apply, meaning clouds/rain, probably for the entire week at least.

#2 smiles233


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Posted 26 October 2021 - 02:04 PM

I would say yes.... especially if you have temperatures that decrease fast
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#3 Don W

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Posted 26 October 2021 - 02:10 PM

No SCT is free from the effects of dew. A dew shield or dew heater will save you a lot of grief.

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#4 c2m2t


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Posted 26 October 2021 - 02:27 PM

Hi Anony!

A dew shield is a necessity...if not dew, than stray light. I have made several over the last few years for several scopes, refractors and SCT's. A material that works very well is the foam underlay that one uses below Engineered (klick) flooring. Don't be afraid, if you try this stuff, to keep it snug. The material can stretch quite easily and takes 10 to 15 seconds to return to its normal static length.


Cheers, Chris. 

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#5 epee



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Posted 26 October 2021 - 03:00 PM

I consider a dew shield a necessity with an SCT. Even if dew is not your problem, stray light will be in all but the most pristine environments and even then there is the Moon. If you don't notice the stray light without a dew shield, try observing with a dew shield and you'll notice it from then on.

Edited by epee, 26 October 2021 - 03:02 PM.

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#6 maroubra_boy


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Posted 26 October 2021 - 03:35 PM

If you find your scope isn't dewing up, then you are fortunate.  But it will happen...


You certainly can make a dewshield out of whatever material that you have at hand.  Foam is great because if you make it long enough you can also wrap the whole length of the OTA to insulate it, this way you eliminate any cooling wait period and are able to crank high magnification from it without the effects of a thermal plume because the insulation prevents this plume from forming.  I've been insulating my SCT's and Maks for several years now and I've made these wraps double up in the purpose of insulation wrap and dewshield.


For the C5 I had I made out of Coreflute (1st pic).  I've used Coreflute and a yoga foam mat (2nd pic) to make my wraps/dewsheilds.  Many people use a material called Reflectix or any of the different similar types of material.  It really just comes down to you as to what you prefer, with one consideration being it needs to be light weight so not to cause other problems with balance and excessive load.  The dewshields I make easily come off for packing and the materials are all easy to cut so that they can be adapted to fit around items attached to the OTA such as finderscope shoes and dovetail plates.



Attached Thumbnails

  • C5 wrap - Copy.jpg
  • Alex sketching Moon - lo res - Copy.JPG

Edited by maroubra_boy, 26 October 2021 - 03:37 PM.

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#7 JMP



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Posted 27 October 2021 - 09:42 AM

I found a black plastic flower pot that was just the right size and used that on my C5.
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