GSO 10" Deluxe vs GSO 12" Ltd

lost_in_space · #1 10-01-2006, 10:05 PM

My telescope procrastination is almost over. It's down to either of the above 2 scopes. There is $100 difference between the 10" Deluxe and the 12" Limited GSO dobs.

Given the deluxe has a fan, a crayford focuser and better glass for the main mirror, in the considered wisdom of this group would the better features of the 10" be worth sacrificing for the extra aperture of the 12" with the $100 difference going into better EP selection?

My inclination is to go with the 10" after all I have read in the forums here. Thoughts anyone?

iceman (Mike) · #2 10-01-2006, 10:14 PM

You don't mention 12" deluxe!

It's a tough choice.. aperture rules, so I'd go the 12", and then spend $99 extra ontop to get the GS crayford put on. You don't need to worry about the fan just yet, although it's handy to have.

As long as the 12" is portable enough for you, moving in and out of the house, to and from dark skies etc, you'll love the aperture!

asimov (John) · #3 10-01-2006, 10:14 PM

Hmmm...I don't know all the specs on the 2 in question. Seeing aperture is supposedly king, I think for an extra $100 for 2 more inches would temp me.

Doesn't the 12" come standard with a crayford these days?

slice of heaven · #4 10-01-2006, 10:21 PM

Go the 12". Aperture upgrading is the most expensive item, focusers..fans.. add them as you can.

Astroman (Andrew Wall) · #5 10-01-2006, 10:22 PM

Go with apature you can always build on it.

Robert_T · #6 10-01-2006, 10:25 PM

I reckon you''l be happy with either... if I were starting out myself I'd take the 10in because I'm lazy and I'd want to make sure size didn't put me off carting it around and using it.

good luck

mickoking · #7 10-01-2006, 10:26 PM

G,day

A telescope will work fine with out a crayford focuser or a cooling fan so I would go for the 300mm Dob.

ballaratdragons (Ken) · #8 10-01-2006, 10:30 PM

It is well worth paying the extra for the 12" but get it with the Crayford!!!! Pay the extra for it.

Don't worry about the fan. One can be fitted any time, they are only 12v computer fans.

As for the quality of glass, because we don't get down to minus 15 degrees any of the optical glasses will do. Plate Glass, BK7, or Pyrex. With Australias weather you will never see any difference between them. But if you are worried about using Plate Glass, the 12" deluxe has BK7 Glass, and the fan already fitted. And a Crayford Focuser!

Look down the bottom of the page on this link and you will see:
Guan Sheng GS-980-BK7-CRF
$999.00 AUD

BK7 = BK7 Optical Glass (good stuff) CRF = Crayford Focuser (lovely)

http://www.andrewscom.com.au/site-co...-dobsonian.htm

p.s. I'm not saying this just because I own a 12" Deluxe. It's because they are a good buy! And coz I own one!

I will mark 12" in your poll, but recommend you get the Deluxe!

lost_in_space · #9 10-01-2006, 10:31 PM

The 12" Deluxe will push me over my budget with the other kit I am buying. It's tempting though. Freight is the same for 10" and 12" to Tassie. I am not frightened of getting the basic model and modding it to my requirements though, in fact I am planning some serious mods anyway.

Bugga, you guys are supposed to be helping me, and now you are making me change my mind all over again

Seriously though, I appreciate the comments so keep 'em coming, and WILL make a decision in the next couple of days.

wavelandscott (Scott) · #10 10-01-2006, 10:41 PM

Without knowing you physical size, vehicle and how far from dark skies I will error on the side caution...get the 10 inch deluxe and put the extra $100 toward a quality widefield eyepiece...

Yes, "size" does rule but I reckon you will enjoy looking through a better eyepiece or two as much as the extra light...the 10 inch maybe a little easier to handle and the "deluxe" stuff (crayford and fan) are things you are ultiimately going to modify up to sometime anyway...

My 2 cents...

janoskiss (Steve H) · #11 10-01-2006, 10:44 PM

If transportation is not an issue (when you want to take it to darker skies), then get the 12". There is a big difference in this regard between the 10 & 12". As far as the extras go, Crayford, fan, ... you can always get these later as more funds become available.

ballaratdragons (Ken) · #12 10-01-2006, 10:51 PM

Yeah, after a bit of thought it would be cheaper to get the standard 12" at $799 and buy a Crayford Focuser at $99 and fit it yourself! All up it is $100 cheaper than the Deluxe and you still get an excellent 12".

The difference between a 10" and 12" isn't just 2" either. There is a mathematical way to work out the extra surface area (light gathering power) but I don't know it. But it is quite a big difference!

acropolite (Phil) · #13 10-01-2006, 10:55 PM

Go the 12 inch, the other niceties such as fans and crayford, you can add later for not much extra cost (just over 100 recession riddled buckazoids). On the other hand the 10 inch can't easily (or cheaply) be made into a 12.....and the 12 inch has 44% more light gathering area than the 10 inch....

gaa_ian (Ian) · #14 10-01-2006, 10:55 PM

I have the 10" Dob, but so long as you can transport it, go the 12"
Remember the #1 Rule: Aperture rules !
When you are trying to tease detail out of the humonculus nebula, or see the Spiral arms of NGC 1365 etc etc ... you will be glad of the extra aperture !

danielsun · #15 10-01-2006, 10:58 PM

yes i agree with steve . go aperture 12" focusers and stuff can be put on later BUT if you go 10" then go SAXON cause SAXONS RULE!!!!!!!!!!............

ballaratdragons (Ken) · #16 10-01-2006, 10:59 PM

Does anyone know the formula for working out the extra % surface area between a 10" & 12" mirror?

lost_in_space · #17 10-01-2006, 11:03 PM

Quote:

Originally Posted by ballaratdragons

Don't worry about the fan. One can be fitted any time, they are only 12v computer fans.

As for the quality of glass, because we don't get down to minus 15 degrees any of the optical glasses will do. Plate Glass, BK7, or Pyrex. With Australias weather you will never see any difference between them. But if you are worried about using Plate Glass, the 12" deluxe has BK7 Glass, and the fan already fitted. And a Crayford Focuser!

The fan is not really an issue, as I am a computer tech. Temperature may be an issue though, it can get down to -5 here on a clear winter night, and has gone as low as -9.

janoskiss (Steve H) · #18 10-01-2006, 11:04 PM

Daniel, I know you like the altitude motion tensioner adjustment, but is there anything else about Saxon Dobs that RULEs over GSO Dobs?

acropolite (Phil) · #19 10-01-2006, 11:05 PM

pi r squared gives the area Ken but if it's a percentage comparison you can forget pi. Work it out like this. 10 inch (250mm) is 125x125=15625. 12 inch (300mm) is 150x150=22500 Difference is (22500-15625)/15625 which is 44%.

danielsun · #20 10-01-2006, 11:16 PM

Sorry to go off the topic but i had a giggle imagining all you GS owners must have read that and simultaneously went

in unicen!!!