10" vs 12" Dob

[[1ponders] (Paul)]

Randall, I think you need to come back out to Cambroon and compare the 12" of Nightshifts, the 16" of Astroron's and the 25" of Argonavis.


Then see which one you want

Then get the 12"

If transportation is an issue consider the option of a Truss Dob

[Gargoyle_Steve (Steve)]

Paul the trouble with that plan is that Dennis's scope will have that lovely candy apple red tube by then - I think that's gonna cause a biased opinion!

(Can't wait to see it Dennis!!!!!)

[drmorbius (Randall)]

Good point Steve... maybe I'm worrying too much about mirror size. Maybe I should be trying to find a scope with the right colour scheme.

Rats... red's been taken!

[astro_nutt]

Ahhh!..what to choose!!!...If you plan to have it at home, or you can transport it without hassles, (you can buy one of those mini-trailers from Kmart for about $450.00)..then go for the 12 inch. I agree..the light collecting ability speaks for itself and you will be rewarded with brighter images..I own a 10 inch dob and a friend of mine has brought himself a 12 inch Lightbridge..the diffrence is noticeable between the two..use and enjoy!!

[Gargoyle_Steve (Steve)]

Randall I was originally set on getting the 8" dob, right uo until I was actually on the phone with Lee Andrews ordering .... something happened at the last minute, and as you know I have the 10".

In terms of pure light gathering ability here's the simple facts: if we ignore the obstruction of the secondary mirror a 6" reflector will gather 36 "units of light" (uol) compared to an 8" 64 uol, a 10" 100 uol and a 12" 144 uol. Based on that I did find the 10" to be the best value.

The only thing I Can say is do what you are planning in terms of getting the "Deluxe" version with Crayford focuser, and if you can get the upgrade to the 10:1 fine focus unit at a reasonable price do it. (I have heard it's $20-40 depending on whether you go Bintel or Andrews, but feel free to haggle AND mention you are from the IceInSpace forum too).

As said above it's all a matter of transport vs cost - whichever you buy I can guarantee you will enjoy it, be it white, black, or even candy-apple red!!

(and Dennis's powder-coater IS apparently in the Caloundra area somewhere anyway - we might even get a 2 for 1 price off him )

[dhumpie]

The solid tube 10" GS is just the right weight and length to fit across the back seat of most small compact cars. The 12" GS is a good deal heavier and longer (the OTA I mean) so that is why most people go for the 10" GS. I know because I did.

Darren

p/s: from memory the OTA of the 12" weights as must as the 10" OTA and mount put together...doable but more hassle...

[ballaratdragons (Ken)]

Originally Posted by dhumpie

p/s: from memory the OTA of the 12" weights as must as the 10" OTA and mount put together...doable but more hassle...

Darren, where do you remember those figures from? You are waaaayyyy off the mark.

GS 10" (250mm) OTA - 15.5kg, Base - 12.2kg Total - 27.7kg

GS 12" (300mm) OTA - 19.5kg, Base - 13.5kg Total - 33kg

Yes the 12" is slightly longer and heavier than the 10", But double????

Randall, and anyone else wanting the FACTS on dimensions, look here for every spec you need on all GS scopes; weight, length, diameter etc: http://www.telescope-service.com/dob...iansstart.html

I personally don't have a problem carrying, moving or transporting my 12" but you may want a slightly smaller scope for ease.

'Sup to you

[dhumpie]

Oops...thanks for the correction Ken. Still between the 10" and the 12", I would still go for the 10" if I had to do it all over again. Its one of those comfortable, do it all apertures...

Darren

[vespine]

Originally Posted by ballaratdragons

Yes the 12" is slightly longer and heavier than the 10", But double????

Obviously it isn't double, but I think the point is that the diff between a 8" and a 10" is not nearly as proportionally large as the diff between a 10" and a 12", I was actually a little surprised when I saw them in person. An extra 2" diameter and 250mm length doesn't look very significant on paper.
I guess the main reason is because the 8 is a f/8, length is 1200mm. The 10" is a f/6 length is a similar 1250mm while the 12" is a f/5 at 1500mm.

At the end of the day, I still went 12"