Astronomy telescope question: Size vs Stability

[g__day]

Guys and gals hello, this is my first post here. I searching for someone in the know to offer a informed point of view on my 3rd telescope purchase.

Basically I'm planning on getting my next telescope in the new year to do astrophotography, and I'm pondering which of three scopes is the better investment. The choices are fairly similar in price around the $5.5K mark, but its a trade off of light gathering ability (aperature) vs the ability of the mount to really point with accuracy.

So its a choice of a $300 - $600 CCD + either

Meade 10" LX200GPS $5,195 - brilliant mount, smallest aperature

Celestron 11" CPC $5,500 - excellent mount, bigger aperature

Meade 12" LX90-LNT $5,599 - decent mount, biggest aperature

So basically its a light gathering vs mount tracking decision. Unfortunately nearly all high end astronomy shops sell only Meade or Celestron - so there is no good unbiased advice.

Also I live in light polluted Sydney, so not sure if this affects my decision.

Could anyone recommend an informed point of view or a source of information online to get a good sense of how to make this new hobby decision go right.

Many thanks!

[rumples riot]

All those are good scopes. The 12" is a big scope and very heavy, so too is the 11". The 10" is managable but still a beefy scope. All have good mounts and it depends on what you are doing or want to do with it.

Light pollution can be a drama but all these scope will give you good views even in those conditions.

If you are interested you could go have a look in the buy and sell forum for a 10" Lx200 GPS UHTC that I have for sale. It is in prime condition and comes with a JMI hard scope case. There are other items I have for sale which could make a nice package for you. Anyway, I don't want to hijack your thread.

Other places to look for info is cloudynights.com , they have lots of information and reviews. Our site is good but we are only a year old. Other places to look is http://www.californiastars.net and click on the banner for Meade.

Congrats on your choice to join the big league.

[cventer]

If astrophotography is your intended purpose then I would have to say you should reconsider all of those scopes as none of them are good platforms for starting out in astrophotography. Im not saying you can't use them bit the learning curve for DSO imaging with large apperture and long focal lengh scopes is long and frustrating....

Also the LX90 does not have all the autoguiding/pec options and microfocuser that the LX200 line does which is a major factor for astrophotography.

If you are new to astrophotography then I do not suggest an SCT to start out. Unless you buy a widefield scope to piggyback on top and use that as your learning platform. There is a saxon ED80 going for 450 in the for sale forum that would make the perfect learning scope for astrophotography mounted on top of either the Celestron 11" CPC or the Meade 10" LX200GPS. Once you have mastered this then you can stick the camera into the back of your SCT. I have an article in the next Sky and Space and the topic should explain clearly the reasoning behind this advice... It comes from experience as I did extactly what you are about to do....

FYI You should be able to pick up a VERY good deal on a 2nd hand meade lX200 as many are upgrading to the RCX400's

Best Regards
Chris Venter

[beren]

I would choose stability over the slight edge on aperture the LX90 12" has , think it would be fine for visual , unlike the 12'lx200 it sits on the standard field tripod and the fork arms don't look particularly overwhelming for the OTA. I have a 10"LX200 and just started out imaging with a DSLR , there's a lot to learn and its tough to produce acceptable images through the SCT and i mainly use a 80mm refractor piggyback for imaging as i climb the learning curve . The pointing accuracy of the scope has always amazed me , sometimes I haven't even checked while centering after a GOTO to check if a object is suitably framed and gone ahead with the image.

[iceman]

I agree with Chris, if astrophotography is your main purpose, I'd like at getting an ED80 on top of a EQ6. Tidalphase (forum member) went down this path recently (using a 350D DSLR) and is producing great images after only a short time.

Also, your budget for a CCD is way under what you'll need for decent images. For that price, you'll get a Meade DSI or DSI Pro, and some people are doing good stuff with them, but they take a while to master by the looks of it.

If you've got a DSLR, that's a great starting option once you buy the adapters to mount it to your scope. If you don't own one, it's still a good option but it will set you back $1000-$2000 depending on what lenses you get with it etc.

I guess you really need to consider aperture vs astrophotography. Large aperture for astrophotography requires a very solid mount (at least an EQ6) and accuracy is even more important at the longer focal lengths. The ED80 gives you nice widefields and is a good entry level into astrophotography.

Light polluted Sydney will be a problem, but filters can overcome some of that. But you should also be prepared to travel with your scope to some dark skies every so often to take advantage of them! We have some viewing nights at Kulnura on the Central Coast (only an hour or so north of you), and it's well worth the trip to meet up with some like-minded guys, and several of the regulars will be able to give you some good advice on-site.. One has a Losmany G11 mount, with a Celestron C11 on top and a SkyWatcher 80mm on top of that. It's a magnicifent looking setup.

Hope i've helped.

[iceman]

Oh and also, IceInSpace is having a star party at the end of January, only a few hours drive from you. Really dark skies, good company and lots of telescopes!

Read all about it here: http://www.iceinspace.com.au/?iisac

Hope you can make it.

[g__day]

Thank you all for your replies, the fever gets in your blood after a while, call it 'scope creep (pun intended).

For some reason the 10" - 12" scopes just appeal - maybe irrationally so. There seem to be lots of guides how to buy your first scope, or even second. But not third, fourth and fith if you catch my drift.

Yes it does make sense to ensure the scope can travel occassionally. I have 3 kids 7, 9, 11 - old enough to enjoy camping and a bit of star gazing...

Niel at Astro-optical wrote back to me today, saying:

"Hello Matthew

The decision of which telescope you purchase depends on the primary use.

If your primary use is for CCD imaging, pointing accuracy is preferable. Longer exposures would be required with a smaller aperture, however with digital technology such as stacking images, this is not a major issue.

If your primary use is for visual use, the larger aperture is preferable.

Best Regards

Neil"

So it takes a bit of figuring. A few more questions:

1. Are the Celestrons as good quality - optics / pointing as Meade (compare and contrast)

2. What is a good balanced spend for a CCD for a 10" - 12" telescope? Should I spend $300, $600, $1,200 or $3,000? What is a reasonable figure and why?

3. Beside scope / mount / wedge / PC - what else do I need (e.g. focal reducers, auto guides etc...)

4. What filers do folk recommend for light polluted skies (something that cuts Sodium based lights I guess) and how effective are these?

Finally does anyone have a strong feel for the 10", 11" or 12" configurations and if there is a clear winner and the why of it - else its more research for me.

Thanks everyone for all the help so far!

[Hitchhiker]

Hi g_day, I'd definitely recommend you get a Focal Reducer if you go the 10"-12" SCT route. This would let you start out on DSOs by doing short exposures in Alt-Az mode. I'm currently waiting for Santa to deliver a F3.3 focal reducer for my 10" SCT. Knowing what I know now, I would have bought it with the scope.

Of course, if you want to bag the dim deep sky objects from day 1 you are going to need a good quality wedge straight away and a guidescope or off axis guider.

[g__day]

So to summarise people's points of view:


1. A large SCT isn't the easiest place to start astrophotography

Agreed, but I want an all round scope for versatility. I'm prepared to invest more time to learn how to drive it fully to have a scope that has a greater range of use and performance. Too it doesn't have to be that mobile 98% of the time it will be fixed on a second floor balcony in a light drench surburb!

2. If astrophotograghy is a priority go for pointing accuracy over light reach

But where is the switchover point (minutes) between light gathering ability and stability?

This means the Celestron 11" vs the Meade 10" LX200 seems the main game. What do folk think of each and how to decide on against them - pointing accuracy, features and add ons, financial viability of Celestron as a going concern etc?

Secondly is the 12" LX90 really only fit for shots under 3 hours, under 2 hours, under 40 minutes, under 20 minutes etc? Where does it start to die? If it could easily do a shot of up to say 3 hours or even 90 minutes isn't that enough given the light pollution of where I live. So is it actually back on the table as the best choice? The difference between the 12" LX90 and LX200 is about $2,000 - which give the optics and stand are the same its the mount that has soaked up all those extra $ for better / finer gears and actuators. Thats alot of money for gears! I'm sure it is worth it, but when does this factor kick in? What is the cut-off point that says beyond this limit move from greater light gathering to pointing stability?

3. Go to a star party - meet great folk, ask lotsa newbie questions

Agreed, seems like a brilliant idea and a way to reality check all my assumptions rather than just jump in. So far my only experience with 8", 12" and 16" SCT is visiting Macquarie University one cold Winter's night and seeing what each scope could do. No planets were in sight, the Optics were smudgy from many little fingers touching them and even though well rugged up my kids wanted to leave within 45 minutes due to exposure. So call that one a very limited success.

I don't have to rush so I'd rather learn and make better choices. I want my next scope to last for a very long time!

[iceman]

Well if you're in Sydney, come to:

1. Kulnura observing meet on the 1st Jan 2006. It's on the central coast, not far from you.

2. IISAC (http://www.iceinspace.com.au/?iisac) at the end of January.

Both great opportunities to meet some IIS forum members and see many different types of scopes.

[acropolite]

The 12 inch LX90 is an unknown quantity; I haven't read any reports of performance but I would imagine that the same limitations that exist with the 8 inch would still be there (no mirror lock, clearance issues with fork, less accuracy possibly fork flex etc). There is additional hardware required to enable astrophotography on an LX, wedge, guidescope (+APM for LX90) etc. If you're hell bent on an SCT why not consider a losmandy G11 or EQ6 mount and C9.25 or C11 OTA, then you'll have decent astrophotography platform and good visual performance as well. Take a look at some of the results Striker has been getting with that setup. Rumples has gone that way as well with a C9.25 and EQ6.

[g__day]

Becuase I'm learning and don't know these things yet! I presumed a fork mount would give more stability then most equatorial mounts (based on what Medae use rigth up to their RC scopes). Only Celestron offer SCTs on forks and equatorials.

More information is delightful, especially if it answers the questions I asked.

[gbeal]

g_day,
I seriously doubt you can bowl this in one fell swoop. Most, if not all here have started with "scope X", and moved to "scope Y".
I have had many scopes, and all have done different things differently.
In the light polluted area in which you live maybe thing about lunar and planetary imaging to start with, and go from there.
While I am not an advocate of the fork mount, it certainly offers a lot of value for money, so look to buy a used LX200 or similar.
The Rumples scope will get you started, but I doubt it will be your "only" scope, BUT it will teach you what you need, or don't need.
Gary

[ballaratdragons]

Matthew,

I am wondering why you only chose SCT scopes for your planned Astrophotography trail?

I have nothing against SCT's but I would expect a Reflector or Refractor to give better results in capturing. (correct me someone if I am wrong)

[g__day]

Merry Christmas everyone!


I choose SCT for 1 compactness - they'll fit in the limited balcony space where I wish to place them (ever practical) and secondly because I see them as an all round scope with excellent value for money. So if I just want to star gaze or snapshot I can do either well on an SCT.

I got sick of reflectors always rotating the tube so I vs kids could see. With an SCT or MAK there is less need to move the eye piece, especially as I got a cheap bar room stool that is very height adjustable to allow kids to see easily and save my back!

The first scope I ever viewed on was my grand parents 3.5" refractor - quite decent at the time I thought (35 years ago or so), but I'm sure scopes have progressed along way since then.

One thing I have gleaned from this thread, I might be better doing astrophotography with a refractor and general viewing from an SCT?

Yes I see this won't be my last scope (much to my wife's sighs of another endless hobby), its just a step along the journey! I ponder more gazing from refractors and SCTs before I buy might be a very sensible thing! Whilst I don't expect a decent scope to challenge HST, I do expect to understand what it can and can't be expected to do in my locale.

Thanks all for the very useful information you have shared!

[atalas]

g_day also check in with (BINTEL Sydney)for your scope advice, they have plenty of It and there after sale service is second to none ! being stargazers themselvs for many decades there advice invaluable .

[[1ponders]]

Hi g_day. jm2cw

I started the same as you, came to my third scope and started wondering what to get. Like you I wanted to do visual and photography, nothing too cumbersome to move around and with the potential to do some deep deep stuff.

I ended up going for the LX200 with a wedge (if your going the LX way you will need to get a wedge). I've since moved on to equatorial mounts as I found the setup much more user friendly than using a wedge. I decided to stick with the Meade 8" OTA (with mirror lock, important to consider to reduce potential mirror flop) and an Orion 80ED refractor. Along with a couple of moderately good camera lenses and a Canon 300D these options cover just about anything I'd be likely to try to image. Along the way I also picked up 6.3 focal reducer, ToUcam and a DSI so I'm covered for everything from lunar/planetary, very widefield, widefield (80ED), and deep sky with auto guiding options.

Hope that helps