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Lyinxz
17-03-2009, 07:59 PM
Hi All,

Ive been trying to find a Dew Shield for my 10" SW C-DOB.
The only thing close to - was this from Bintel:
https://www.bintelshop.com.au/Product.aspx?ID=5511

Though it does say its for SCTs.

Question - do you think it will still fit my scope?

If not, anyone know any places I could get one from?
Prefrebly from a astro shop based in AUS.

Thanks for reading.

Cheers,
Ash

wavelandscott
17-03-2009, 11:18 PM
You can measure and see if it will fit...if the measurements are right there is no reason that it won't work. You might check the weight to see if it will make your scope too top heavy.

Somewhere there is a formula to determine the "optimal" length to get the most protection without negatively impacting on your field of view...I don't recall it at the moment...

Alternatively, you can get some light weight "foam" material (like a camping mat or similar) and make your own. Easy and light weight is the key...attach some velcro to it and viola! You have a Light (and lite)/Dew shield.

Another option would be to go to a speciality plastic shop and get a sheet of light weight and flexible material, measure and cut and make a fastener...

Very simple and generally cheaper than store bought.

I've done all 3 at different times and they all worked well.

Cheers,

erick
17-03-2009, 11:28 PM
I wandered through Bunnings and found a roll of damp course material that was black plastic and the right width. Cut off a piece, added two strips of velcro and I have a dew shield for my C8. Sags a bit but doesn't get in the light path. And I can fit it over my corrector plate dew heater. And I have enough on the roll to make another - well, several dozen!! :D

Lyinxz
17-03-2009, 11:40 PM
Thanks for the idea guys, does sound interesting.

Though I would rather purchase one that looks *pro (since im a perfectionist haha) than a home made one. espically since my home made skills are shockers haha.

I made a light shroud for my scope ... bad idea. waste of $60 on material haha.

So id rather have one thats commerically made to fit.

Il keep looking tho!

thanks for ur thoughts.

bluescope
17-03-2009, 11:49 PM
I made dew shields for my 8" and 10" newts and also my 180mm mak with 2 or 3mm foam rubber similar to wetsuit material that I purchased from a store called Clark Rubber here in Perth.

You just measure the outside diameter of your scope at the end for the length you require ... allowing for an overlap of an inch or two ... I made my shields about 30cm wide ... cut the foam rubber to size and then attach self adhesive velcro ( buy it from fabric shop ) to both ends of the rubber. From memory the rubber cost me about $27 dollars for the roll and the self adhesive velcro was very cheap ( a few dollars again from fabric store ).

They work very well and I still have lots of materials left over if I should need to make any more dew shields in the future.

:thumbsup:

p.s. I just read your latest post and see you would rather have commercially made shields ... now worries !

Starkler
18-03-2009, 01:15 AM
I have never heard of a commercially made 'dew shield' for a newtonian.
Actually in the case of a newtonian its function is as a light shield, not a dew shield.
Most people just make their own from any convenient material. Rule of thumb is to make the length so that the tube in total extends 1.5x the primary mirror diameter past the focuser.

astronut
18-03-2009, 08:52 AM
Ash,
I use a product called H.I.P.S, High Impact Polystyrene Sheet.
I've velcroed it together. It's very strong, flexible and can be cut with a pair of sharp scissors.
The sheet I bought was 1.73m x 50cm x 0.75mm, approx $20.:thumbsup:

Lyinxz
18-03-2009, 06:36 PM
Looks like I will have it to make my self then eh?

I like the look of yours astronut.
Where did you get the "HIP" material from?

xnomad
18-03-2009, 07:58 PM
I've only been a telescope owner for a few weeks now and haven't experienced any dewing. After reading so many times that SCTs and MCTs are prone to dewing I've been waiting for it. I've only used my scope up to around 11:00 pm and at around 5:00 am.

I'm just a suburb or two away from you Ash, do you get dewing often? I'm dreading having to add another item to my shopping list.

Lyinxz
18-03-2009, 11:40 PM
Hey Nomad,

haha tell me about, the amount you end up forking out in acesories is just crazy:sadeyes:

I have only taken my new 10" out a few times and have not recieved any dewing around our area.

However having said that with my old scope 4.5" newt EQ I did experience dewing quite heavily at my dark sky location at Terry Hills.

I think when the season changes we will see the full extent of it.

PS: if you live close by, let me know if your interested in meeting up some place for a observation session. :thumbsup:

Cheers,
Ash

astronut
19-03-2009, 07:41 AM
AllPlastics Engineering, Chatswood. www.allplastics.com.au

xnomad
19-03-2009, 07:38 PM
Hi Ash,

That's funny, I work just down the road from Terrey Hills. I've been thinking about finding a spot around there to have a look.

I was even tempted to use the upstairs deck at work sometime. Yeah that would be good to meet up with a fellow star gazer as everyone else I know isn't at all interested in what I'm talking about.

gb_astro
19-03-2009, 10:11 PM
Hi Ash.
That HIPS looks pretty shiny, not usually recommended for light shields.
gb.

astronut
19-03-2009, 10:46 PM
The H.I.P.S is only shiny on the outside, the inner shield is a very flat matte finish.
You could also use adhesive backed black felt to line the inner shield if necessary.

gb_astro
20-03-2009, 09:41 AM
John, thanks for the correction.
Sounds like the right stuff then.
gb.

Lyinxz
20-03-2009, 11:05 AM
Hahaha yes all my mates also have 0% interest which can make it quite a lonely hobby (thank god for IIS haha)

I'm waiting on setting up a "Argo Navis" I recently purchased. Once I have that setup then I'l be back under the night sky. I'l drop you a PM and we'l see if we can arrange something.

I usually go to the Pony Club in Terry Hills. (just near terry hills tavern)
Its not to bad on a moonless night.
Good if your local around the area.

You should check out IIS pony club in Mangrove Mountain Central Coast, They have monthly sessions there. I think they are going tommorow night actually. Its a bit of a trek for sydney siders but well worth it! Ive been once and the sky there is just awsome.

xnomad
23-03-2009, 03:26 PM
Sounds like a plan. Speak to you then. :thumbsup: