Big Dob time .. Opinions please

[prova]

I've done alot of reading and never plan to go to anything like a 20"+ so I've decided to go for a 16" Lightbridge and initally buy a set of wheely bars, astrozap shields.

I do have to save a little more but I think I'll be dissapointed buying a 12" after looking through the 16" owned by a local (used to be here on IIS).

If anyone is looking to sell their 16" LB, please send a PM!

[Paddy (Patrick)]

A good move I reckon! 12" good, 16" better! Each time I compared my 12" with a 16" (be it a lightbridge or custom made) I found a quite significant difference in the detail that I could observe.

[bobson (Bob)]

I will have to agree with Calibos and what he wrote about 12" and 16" dobs, he wrote:

"That said, I am not expecting to be blown away by the move from 12-16in. Got my first look through a 20in a few weeks ago and while initially I thought WOW when I went back to my heavily modded albeit standard Orion Mirrored Orion XT12i and looked at the same objects through the same eyepiece, what I thought were new details revealed by the 20in were in fact there in my 12inch scope. I just hadn't noticed them before."

Just a couple a weeks ago I had a chance to compare my 12" Bintel Dob with friends Meade 16" Light Bridge and I was not blown away
Mind you, 16" was better but just not that better that I would spend another $1500 for it. In my opinion that money would be better spent in buying couple of good quality eyepieces.

This is just my opinion regarding 12" and 16" dobs.

[ausastronomer (John Bambury)]

Originally Posted by bobson

I will have to agree with Calibos and what he wrote about 12" and 16" dobs, he wrote:

"That said, I am not expecting to be blown away by the move from 12-16in. Got my first look through a 20in a few weeks ago and while initially I thought WOW when I went back to my heavily modded albeit standard Orion Mirrored Orion XT12i and looked at the same objects through the same eyepiece, what I thought were new details revealed by the 20in were in fact there in my 12inch scope. I just hadn't noticed them before."

Just a couple a weeks ago I had a chance to compare my 12" Bintel Dob with friends Meade 16" Light Bridge and I was not blown away
Mind you, 16" was better but just not that better that I would spend another $1500 for it. In my opinion that money would be better spent in buying couple of good quality eyepieces.

This is just my opinion regarding 12" and 16" dobs.

Hi,

Some of this comes down to observing experience. It can take several years to properly develop and hone ones observing skills to see very faint detail in extended objects. An experienced observer under "dark" skies can sometimes detect a significant difference between a 12" and 16" scope, on dim extended targets, like galaxies, galaxy clusters , dim diffuse open and globular clusters and some planetary nebula. A less experienced observer may not see an enormous difference between 12" and 16" scopes, on the brighter targets, particularly under less than pristine skies.

That having been said, you can do a lot of very serious observing with a 12" telescope. A lifetime of it in fact. In the truss design, a 12" scope offers IMO the perfect compromise between portability/ transportabity and what you can see with it. It will go deep enough to see enough objects that you will not cover them all in a couple of lifetimes. It is also big enough to turn the bright showpiece targets into "eye candy".

Cheers,
John B

[Calibos (Keith)]

Hmmm, errrr.....its not a case of speaking too soon in the post last night because tonights first light was on pretty much 1 object and one can't judge from a sample of 1 but......

Tonight I had a beautiful clear sky but as usual its during the time of the month near full moon. The moon was 90º away from the target. My scope hadn't cooled down. I didn't have a shroud, I haven't painted the endrings yet or fit a lightshield so the 2 orange streetlights about 20ft each side of my viewing position lit up the focusser, inside of mirror tub, endrings like orange neon, all visible in the eyepiece. I was only out about 20 minutes so even if it were pitch black I would not have been fully dark adapted and so with the streetlights making the street like a hazy orangey sunset/dusk, I definately could not have even started getting dark adapted.

So this was not an observing session or observing first light. This was basically just to test out my intelliscope mod which worked beautifully btw.

The target I tasked the intelliscope with successfully locating?? (I can find it blindfolded obviously, this was for testing the computer )
M42.

Now unless there is something psychological going on in my subconcious hoping to convince me I haven't wasted my money but.....tickle me pink if I didn't have what I believe to be my most detailed view of M42 ever and thats compared to my fully lightshielded, flocked, cooled, boundary layer removing fanned XT12i from my dark sky site!!

Now I don't know, maybe if I had set up the XT12i too to compare side by side I would say the difference wasn't as much as I thought. Maybe I am making the same mistake I did with the 20in view and then realising my XT12i was nearly as good but if tonights short views were anything to go by......I cannot wait to do all my mods and get this thing to a dark site!!

So this wasn't a thorough enough test or comparison to definitively say I was wrong in my last post about the improved views probably not being worth it but the question in my mind is certainly wide open again.

[Paddy (Patrick)]

I have to agree with John about observing experience. Had I compared my 12" and 16" as a novice, I would have found little difference. After a few years of observing, what I can see through my 16" is far more detailed than I ever saw through 12". I also agree that a 12" scope will show enough to excite for many years.

[prova]

Thanks for the all the advise.

I have now set my heart (and my wallet) on a 16" Lightbridge with Argo Navis, main problem is with the US dollar the way it is at the moment is finding one at a reasonable non-inflated price ..

Hmm!?