GSO 10" Deluxe vs GSO 12" Ltd - Page 2

danielsun · #21 10-01-2006, 11:25 PM

Yes Steve it has handles that go through the sideboards and into the alt bearings making it able to pick up the complete unit and carry around easily! and nice thick round bolted alt pads not stapled teflon.

lost_in_space · #22 10-01-2006, 11:37 PM

Quote:

Originally Posted by danielsun

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!!!

I was wondering why you voted "Neither"

janoskiss (Steve H) · #23 10-01-2006, 11:40 PM

Quote:

Originally Posted by ballaratdragons

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

area goes like the square of the diameter (aperture).
Aperture for area,
12" to 10" is like
12*12=144 to 10*10=100,
so the 12" has 44% more area. But the eye's sensitivity is "logarithmic" so this seemingly big change on paper amounts to a relatively subtle difference when you look through the scope.

danielsun · #24 10-01-2006, 11:50 PM

just having a bit of fun cause i know there are a lot of GS owners out there and i was waiting for someone to coment.

But back on track again it seems majority agree if transport is no problem go the 12" !! The GS's are a good scope and the saying goes aperture rules!!!!.

Quote:

Originally Posted by lost_in_space

I was wondering why you voted "Neither"

janoskiss (Steve H) · #25 11-01-2006, 12:06 AM

Daniel, I think I know what you mean about the altitude bearings. They must be like the ones on the Celestrons I saw at York in Melbourne. Great big polyurethane things (at least that's what they looked like to me), very smooth. They felt much nicer than the altitude bearings on my Dob. But they also add bulk (width) to the mount.

danielsun · #26 11-01-2006, 12:34 AM

yes your probably right Steve, the extra material around the bearings on the side plates for the handle set up and the 20 mm polyurethane rollers probably does add a tiny little weight but not much!. but if i was to upgrade again it would probably be a 12 GS with the crayford which is a much better focuser than the standard r&p on the saxons, but as you know the story how would i hide it from the wife, GS's are silver!!!

davidpretorius · #27 11-01-2006, 07:12 AM

12" if not a transport problem as I want you to come to Bridenorth every now and then.

Deluxe or Ltd???

Cooling: The way our temps drop here in tassie during summer, a fan is a must. i have just bought a $30 ball bearing fan the same that is on Simon's 12" bintel. Ian has made up a backing for them to fit around the collimation screws etc, so I believe it would be better to add the fan after purchase.

Crayford: simply a must. Playing with Ian rack and pinion on his 8" and then my crayford on my 10", well there is no question. On the down side, two guys on this site have bought the $99 crayford and have had hassles fitting and getting focus from memory. Now they were for non gs scopes I believe.

So, 12", crayford and a cooling fan must be there eventually. Then a dob driver II and a ..... and a....

Quote:

Originally Posted by lost_in_space

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.

ving (David) · #28 11-01-2006, 03:10 PM

i picked 10" for transport reasons... and lugging around a 12er could be a viewing killer. "its clear, but could i really be bothered lugging this thing outside, the seeing might be bad then I've wasted the energy..." etc.

aperture does rule tho

davidpretorius · #29 11-01-2006, 03:19 PM

vingo.......dob buggy is good!!!.....no transport probs unless stairs!!

ausastronomer (John Bambury) · #30 11-01-2006, 04:05 PM

Well, I have owned 6", 8" and 10" tubed dobs. I have no inclination at present to change my scope.

The 10" to me is the best compromise between cost, portabilty and what you will see. That doesn't mean its the best option for everyone. When I do my lunar/planetary observing from home I like to be seated as you can extract infinitely more detail seated than you can standing. The focuser on the 12" is too high for me to use seated. The 10" also fits perfectly in my wifes car and its also a lot easier to carry in and out of the garage.

Just some things to think about before you jump in head first and then realise
O fu-k !!!!! its a big sucker.

Granted the 12" will show a little more than the 10" but having used both scopes on many occasions I prefer the 10" as being the ideal size for my own observing needs.

The crayford and the cooling fan are also necessary options IMO, if not initially at some time in the future.

CS-John B

Robert_T · #31 11-01-2006, 05:47 PM

looks like the 10 is gaining, but the 12's still got a hefty lead there... decisions decisions

lost_in_space · #32 12-01-2006, 12:55 PM

Thanks for the feedback peoples. In line with the popular choice in the poll I have decided to go with the 12" Ltd with the 4 bundled plossls at 4, 6, 20 and 25mm, (I already have a 15mm) along with a Rigel QF, Cheshire Collimator, GS 26 & 32mm 65deg 2" EP's, and a GS achro 2x Barlow. I also wanted the 40mm GS EP, but Andrews had no stock. I ordered yesterday, and they are shipping today so I won't see it for the weekend.

I figure this is a good enough mixture to get me launched, and will add the Crayford focuser and better EP's once I have looked through others and have a clearer idea of where I am heading with this. The first job I will be doing (after collimating it) is to add either a 80 or 100 mm computer case fan to the base of the mirror cell. I have both, but will need to see which is the better fit.

Suck or blow? I think blow would be better, especially if I can somehow direct the air flow over the mirror to break up the boundry layer effect.

Once again thanks for the great advice, and I'm sorry about the next 6 weeks of cloud cover and bad weather!

davidpretorius · #33 12-01-2006, 01:13 PM

Quote:

Originally Posted by lost_in_space

Suck or blow? I think blow would be better, especially if I can somehow direct the air flow over the mirror to break up the boundry layer effect.!

welcome to the dob team.... we now show you the secret handshake that the SCT boys don't know about and we vacate posting informative stuff on this forum. The new forum address is !#!@#**(((!()))!..!#!#!! (security coded of course.)

The tie and jacket have been sent from headquarters. Words for the dob team song are being emailed and the gentlemen's pleasure evenings with miss universe contestants serving refreshments and cigars start next thursday

---------------------------

Re th fan. Blow if you are from the bottom or if like i have done, i have cut a hole in the side to suck the boundary layer out.

Stay tuned, i have ordered my peltier coolers to builder a cooling system for the base of the newt.

ving (David) · #34 12-01-2006, 01:29 PM

wiggle, wiggle, shake, slap, wiggle.....

acropolite (Phil) · #35 12-01-2006, 08:51 PM

Geez, more bad weather in Tas now....Good decision though..

ballaratdragons (Ken) · #36 12-01-2006, 09:15 PM

Tha fan will need to blow onto the back of the mirror.

Luckily, the 12" has a larger gap between mirror & cell than other GS models, so the air will easily blow around the mirror and across the surface. How do I know this? Whenever I get a fogged mirror I turn the fan on and watch it demist. Also I noticed at Camp that other GS mirror cells are closer to the back of the mirror than the 12".