Boy did I have trouble with those funny letters and numbers:)

[rayw1 (Ray)]

But I made it !!

Hi all, I am planning to buy a Dob and have a couple of questions, first of all I am not really new to telescopes, about 9/10 years ago I had the use of a 10" Dob for a couple of years, and my main interest is finding viewing all those fuzzy bits what I would like to know is ...if I decided to go down to an 8" would I be dissapointed given that I have seen through a 10" is there a big difference, and if I went up to a 12" how much better....more would I be able to find/see,
And now for the newbie in me which eyepieces are most suited for what I want to view, filters ??

Did I say a couple of ?'s .....and ...I am in Perth WA, York Optical used to be here but I can;t seem to find them, or any other place where I can go and have look at what I am planning to buy, well I am sure I will have more ?'s but for now that's all folks

Thanks, Ray

[Craig.a.c (Craig)]

From what I understand is that if you double the size of the telescope, you will gather 4x the amount of light. So an 8" telescope will gather 4x the amount of light that a 4" would.

Eye pieces - I mainly use 25mm to 9mm, others will have different views.

Filters - Depends on your location and light pollution. I use a Badaar moon/sky glow filter to help break down light pollution. It also helps to bring out some more detail in nebulas.

[rayw1 (Ray)]

Originally Posted by Craig.a.c

From what I understand is that if you double the size of the telescope, you will gather 4x the amount of light. So an 8" telescope will gather 4x the amount of light that a 4" would.

Eye pieces - I mainly use 25mm to 9mm, others will have different views.

Filters - Depends on your location and light pollution. I use a Badaar moon/sky glow filter to help break down light pollution. It also helps to bring out some more detail in nebulas.

Thank's Craig,

[erick (Eric)]

Hi Ray. If you are talking 8"/10"/12" on a dobsonian base, a big issue is that of handling and transport. 8", you can move around and transport without much difficulty. 12", you need a pretty big car or a trailer to transport - even carrying the base then OTA out into the backyard is a bit of a task if you have stairs to negotiate!

If you've had some years with a 10", one would imaging that dropping to an 8" may be a little disappointing - but with some good quality eyepieces and more knowledge now of what you are looking for, an 8" might be just fine for you, particularly if that size suits your storage/movement/transport situation.

[Craig.a.c (Craig)]

Originally Posted by rayw1

Thank's Craig,

No morries. Sorry I couldn't be of more help. I'm still a newbie to it all myself.

[garin (Garin)]

Hi Ray,
In Perth you're pretty much limited to Binocular, Telescope and Optical Worls (BTOW) in Malaga. www.btow.com.au.
Once a month they usually have a lunar/planetary viewing night where you can get a look through differnt scopes and ask some questions. Also AGWA holds their monthly meetings there (1st Tuesday of each month - although the October meeting may be different) and this can be a great place to ask questions.
BTOW also hosts 6 week courses cover astronomy in general and equipment (I did this prior to choosing my 1st scope, which by chance was a 8" dob) and a practical night at the AGWA/Starry nights observing area in Chittering.

Getting in touch with an astronomy club (I'm with AGWA) can be a great place to get a chance to look through different scopes and get some opinions prior to purchasing and I've found everyone more than willing to provide advice.

Cheers
Garin

[rayw1 (Ray)]

Hi Garin,
Thanks for the info, I will check out btow at the weekend and also AGWA,
do you still have the 8" dob ? , I had a look at the web site, and the tension control handle looks interesting, does your's have this feature how well does it work,

Cheers
Ray.

Originally Posted by garin

Hi Ray,
In Perth you're pretty much limited to Binocular, Telescope and Optical Worls (BTOW) in Malaga. www.btow.com.au.
Once a month they usually have a lunar/planetary viewing night where you can get a look through differnt scopes and ask some questions. Also AGWA holds their monthly meetings there (1st Tuesday of each month - although the October meeting may be different) and this can be a great place to ask questions.
BTOW also hosts 6 week courses cover astronomy in general and equipment (I did this prior to choosing my 1st scope, which by chance was a 8" dob) and a practical night at the AGWA/Starry nights observing area in Chittering.

Getting in touch with an astronomy club (I'm with AGWA) can be a great place to get a chance to look through different scopes and get some opinions prior to purchasing and I've found everyone more than willing to provide advice.

Cheers
Garin

[rayw1 (Ray)]

Hi eric,
I had no problems with the 10" regarding handling, but maybe the 12" is another story, as you pointed out the need for a big car (I don't have) or use a trailer mmmm not sure about that , I will check them both out though and decide between the 10"/12",, which eyepices would you reccomend for viewing DSO's, also on the 10" Skywatcher Dob they mention that it comes with a Pyrex primary mirror, is this a good thing?

Cheers
Ray

Originally Posted by erick

Hi Ray. If you are talking 8"/10"/12" on a dobsonian base, a big issue is that of handling and transport. 8", you can move around and transport without much difficulty. 12", you need a pretty big car or a trailer to transport - even carrying the base then OTA out into the backyard is a bit of a task if you have stairs to negotiate!

If you've had some years with a 10", one would imaging that dropping to an 8" may be a little disappointing - but with some good quality eyepieces and more knowledge now of what you are looking for, an 8" might be just fine for you, particularly if that size suits your storage/movement/transport situation.

[erick (Eric)]

Make sure you see a 12" before you order one unseen. They are big.

Re pyrex glass:-

http://www.skyandtelescope.com/howto...tml?page=2&c=y

Re eyepieces:-

Depends, of course. Read the many threads on selecting eyepieces. It will either become clear or even more confusing. What you can spend is a big factor in choosing. You can spend $800 on a single eyepiece. You will get an excellent eyepiece. But many sub-$200 eyepieces may give you very satisfying views. "DSO's" - what a huge range of objects requiring all the way from low to high power. Perhaps some of the Televue Ethos owners claim you can do all with one eyepiece. Most seem to recommend at least two and probably three eyepieces of different powers together with a good 2x barlow.

[garin (Garin)]

Hi Ray,
I don't have the 8" any more, I now have a 10" not quite as convienient size wise but the extra light is handy. Problem is you start to suffer the dreaded aperture fever, I recently bought a 16" Lightbridge as I reckon that if I'm going to go big do it earlier while you can still carry it

Maybe I'll see you at the AGWA meeting.

BTW you might find a secondhand scope amonst the members, I know the guy that bought my 8" was selling it. (he has also recently moved up to a 10" on a EQ6 mount)

Cheers
Garin