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Efendy
20-07-2021, 04:51 PM
Hi all,

I've recently bought a nexstar 8se. i am getting ready for spring observing sessions. Melbourne being on the dry side is a dew shield required or I can get away with it in the beginning as I am still a beginner?

Cheers!

Nikolas
20-07-2021, 05:21 PM
Definitely use a dew shield as it does get humid and dewy at night in Melbourne, especially with such a large collector plate.

Efendy
20-07-2021, 05:34 PM
Hi Nicholas,

I'll start looking for one then. Do you have any suggestions to tackle this as I can see there are a few approaches such as a dew shield and/or a heater or a diy solution. I am sure these have been covered in the forums but I don't know if one is better than the other for Melbourne climate.

Many thanks

mura_gadi
20-07-2021, 05:57 PM
Hello,

BOM lists the dew point in its "observations" weather pages for cap cities etc. Might help you plan around dew points a little, dew point goes against the temp. not the apparent temp. The dew shields also help a lot with stray light.

For some reason dew shields are just about all black, lighter colours attracts dew later than darker colours. Keep the inside black, but if you're thinking about crafting your own, I'd suggest a light colour for the outside.



Steve
Ps. One of our members Alex, wrote a reply on why telescope are white, if you want to check it out. (Not so you don't walk into them... apparently)

PPS. Sorry, should have mentioned, if you make your own, include a lip at the bottom of the dew shield. The water should fall away from your dew shield and not trickle on down to your scope - mount etc.

The_bluester
20-07-2021, 06:10 PM
For an SCT, they just about need a dewshield in a vacuum! (I have a C925)

Even with one they will eventually dew up on many nights of the year, the corrector plate is quite thin and radiated heat off into the air quite quickly. With my C925 I ended up with a dewshield, a heater and an eyepiece heater, with that lot it was good all night all year round. The eyepiece heater is not as important, but in colder weather, one errant breath when things have cooled right off can see your eyepiece fogged in an instant.

Nikolas
20-07-2021, 06:11 PM
I use both

Efendy
20-07-2021, 08:41 PM
Hi Steve,
Great tips, thank you.
I would definitely attempt to make one myself and I will keep your suggestions in mind.
Cheers,
Abdullah

Efendy
20-07-2021, 08:46 PM
Hi Paul,

It seems the consensus is using both a Dew shield and a heater
I'll keep in mind.
Cheers!
Abdullah

Efendy
20-07-2021, 08:47 PM
Hi Nicholas,

It makes sense.

Thank you