First things

[oberresford (Ollie)]

Hi All,

Looking for a little advice before I jump in with any initial purchases for my telescope. I've had a dobsinian years ago but im pretty much a begginer.
I've not had my 8" Celestron Evo very long but some obvious things are
1) The plastic red dot finder I find a pain and not reliable, I am thinking to grab a Bintel Finder scope first, unless you have some better recommendations. I had a basic bintel finder years back

2) had the Dew forming fairly quick the other night, having read info seems varying opinions, I live in Melbourne and is a Dew Shield enough or does it need to be combined with a heater element? interested to hear from Melbournites.

3) Finally I've read the 2 polarizing filters combined together make for a very versatile filter, thinking of going for one of these over just a std moon filter ?

Thanks for any tips,

Cheers
Ollie

[iborg (Philip)]

Hi Ollie
I am also in Melbourne and can confirm that a dew shield alone is not enough. Having said that, heating might not be required.
Take a look at this thread http://www.iceinspace.com.au/forum/s...d.php?t=182093
and this one http://www.iceinspace.com.au/forum/s...light=corflute

[mental4astro (Alexander)]

Ollie,

Philip put a couple of good links. A better one than the first is this particular thread as I talk expressly about SCT's and Maks:

SCT & Mak total dew control without heat - a solution!

This link follows on directly with the second one that Philip posted

As for red dot finders, I LOVE them. Some are better than others, and it can take a little getting used to. I tend to use both eyes with them.

I do have and use both optical finders and rdf's. On my big dob when I am at a dark site I use both on the scope, the rdf to do a rough scope placement, and often it is enough, and use the 50mm optical finder for fine tuning when chasing difficult targets. Often the rdf is enough to put the target in the eyepiece, including faint fuzzies.

From home, because of my experience, I am comfortable just using an rdf - I'm not chasing faint galaxies from home. And when I'm aligning my goto systems, I only use the rdf to help locate the alignment stars, and then I'm not using any finder from then on.

With your Evo, you really only need it to help acquire the alignment stars. However, if you are really struggling, a straight through optical finder may be an option. Or both! There are double finder adapters available, even triple finder adapters.

Polarizing filters are great if when you are doing low power observing of the Moon. The Moon can be exceedingly bright in its fuller phases, and a pair of polarizing filters can be a huge help. I also have a set of these, and use them with my 8" scopes only when doing low power work. When using high magnification, no filter. Along the terminator you really don't need a filter.

Also, when observing the Moon, don't bother going to the same extent of using a red light and keeping your surrounds pitch black. There is nothing subtle about the Moon, and it is better and safer for you to keep the porch light on and a white light headlamp as your vision will not be dark adapted with the Moon. Instead, your vision will be stunned, like when going from bright sunlight into a dimly lit room. A dim red light and dark surrounds is not a good combo with the Moon. Again, this is from spending hundreds of hours sketching the Moon,

[oberresford (Ollie)]

Thanks for the information I thought it best to check before I start spending, off to bunnings tomorrow to find some corkflute.

[oberresford (Ollie)]

Gonna start giving these a try get the coreflute first and make something up to begin with see if I get get some felt for the inside.

I'll then move onto to looking at maybe a small usb powered fan I can just run off a small power bank, something like this maybe on ebay :
link

I'll give the red dot another go, the main issue seemed to be there didnt seem to be enough travel in the adjusters on this one and it didnt seem very stable on the scope but I'll take a look first.

Thanks for all this info, always great to get tips like these. Great pictures BTW

Ye the filter is mainly for getting into the Moon.

Cheers
Ollie

Originally Posted by mental4astro

Ollie,

Philip put a couple of good links. A better one than the first is this particular thread as I talk expressly about SCT's and Maks:

SCT & Mak total dew control without heat - a solution!

This link follows on directly with the second one that Philip posted

As for red dot finders, I LOVE them. Some are better than others, and it can take a little getting used to. I tend to use both eyes with them.

I do have and use both optical finders and rdf's. On my big dob when I am at a dark site I use both on the scope, the rdf to do a rough scope placement, and often it is enough, and use the 50mm optical finder for fine tuning when chasing difficult targets. Often the rdf is enough to put the target in the eyepiece, including faint fuzzies.

From home, because of my experience, I am comfortable just using an rdf - I'm not chasing faint galaxies from home. And when I'm aligning my goto systems, I only use the rdf to help locate the alignment stars, and then I'm not using any finder from then on.

With your Evo, you really only need it to help acquire the alignment stars. However, if you are really struggling, a straight through optical finder may be an option. Or both! There are double finder adapters available, even triple finder adapters.

Polarizing filters are great if when you are doing low power observing of the Moon. The Moon can be exceedingly bright in its fuller phases, and a pair of polarizing filters can be a huge help. I also have a set of these, and use them with my 8" scopes only when doing low power work. When using high magnification, no filter. Along the terminator you really don't need a filter.

Also, when observing the Moon, don't bother going to the same extent of using a red light and keeping your surrounds pitch black. There is nothing subtle about the Moon, and it is better and safer for you to keep the porch light on and a white light headlamp as your vision will not be dark adapted with the Moon. Instead, your vision will be stunned, like when going from bright sunlight into a dimly lit room. A dim red light and dark surrounds is not a good combo with the Moon. Again, this is from spending hundreds of hours sketching the Moon,

[oberresford (Ollie)]

Finished stage 1 and created a coreflute shield with a black felt inner.

My first test went very well although it was a milder night, it's looking good though. Next stage I'll look at adding the fan.

Thanks to Phillip and Andrew for the great suggestions only cost me like $30.

Cheers
Ollie