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View Full Version : Skywatcher Skyliner-400P Flextube Synscan 406mm (16") f/4.4 Parabolic Go-To



Astronut1982
2011-Apr-01, 12:48 AM
Hi guys,

First time poster so just want to 1st of all say hi to you all.

I have a question to ask. I'm looking to upgrade my telescope & I was looking at the Skywatcher Skyliner-400P Flextube Synscan 406mm (16") f/4.4 Parabolic Go-To.

What I'm looking for is a telescope thats good for both planetary & deep sky observation & also Astrophotography. Can any of you guys tell if this telescope is any good?

If it's not any good for what I want, can anyone point me in the direction of a good telescope. I'm looking to spend a maximum of 3000.

Thanks in advance for your replies,

Jeff

RickJ
2011-Apr-01, 03:12 AM
Can't answer for its optical quality as never seen one. For planetary photography it would work but not well suited for deep sky work. You'd be limited to stacking many very short exposures resulting in a much lower signal to noise ratio than you'd have with longer exposure time for each sub frame. 100 30 second exposures doesn't begin to equal 5 600 second ones even if the same in total time. Eats up a ton of disk space as well. If the latter is in your plans you will need a high quality equatorial mount which would far exceed your budget if for a scope of this size.

You don't say what you presently have. Don't make too much of a jump. Several in our club went from 6" and 8" scopes to 18 and 20" Dobs and were totally "lost in space", soon dropping out of the hobby.

Rick

redshifter
2011-Apr-01, 06:50 AM
What scope do you currently have? What are you upgrading from? Do you have experience with astrophotograpy? What is your current level of expertise?

Astronut1982
2011-Apr-01, 11:21 AM
Hi,

It probably would have been a good idea to include what I was using at the moment. Doh!

At the moment I have a SkyWatcher Startravel 150mm EQ5 Refractor Telescope with a modified Philips SPC900NC Webcam & registax 5.1.

I have a little experience with astrophotography, I've taken pictures of the Moon, Jupiter, Saturn & some ok but nothing special pics of stars so far. I'm really enjoying astronomy though & want to take it further, I've got the time & the dedication.

The thing is I can't afford to upgrade a little at a time, telescopes & accessories aren't cheap & I also need to buy a good camera as well. My thinking was if I upgraded to a decent telescope now then I could save a bundle in the long term. The thing is, there are so many out there & it's not easy to know which is best for I need. Some of them come with so many gadgets but I don't know whether they're really neccessary or just gimmicks to help sell telescopes to people like me who are unsure of they're looking for.

I was also looking at the Meade LX90 ACF 12" Telescope & Celestron CPC 1100 GPS XLT Telescope but again I'm unsure as to whether they'll be any good for me.

redshifter
2011-Apr-01, 05:05 PM
IMO you should get out to a star party and check out as much equipment as you can. You're trying to plan for a big upgrade that will last you for a long time. It's important to get as much info as possible to avoid 'buyers remorse'.

If it were me and my 3000, I might go for a decent 10" dob as a stricly visual observing scope (here in the US, a decent 10" dob will set you back 600 bucks or so, maybe add 200 more for a couple decent eyepeices), and then put the rest towards a dedicated astrophotography rig.

Astronut1982
2011-Apr-01, 07:43 PM
Thanks for the advice, I will make a point of finding a star party a.s.a.p. I want to spend about 6 months researching this at least, if not more as it would be far too expensive a mistake for me to make to buy the wrong one.

With regards to the dobsonian, would it make a difference to the quality if I bought a truss dobsonian as opposed to a standard one? A truss would be advantageous as I'm transporting it alot in a small car so size is important.

One more question: I've been reading about spectroscopy & wondered if there is any way of doing this with amateur telescopes or is this only possible with professionial ones as I think it would be pretty cool to look at the stars & be able to work out for myself what elements they're made from!

Jeff

RickJ
2011-Apr-01, 08:27 PM
Planetary photography can be done with inexpensive mounts. Aperture helps as you get more light for shorter exposures. Hence the scope would be fine for that but a bear to lug out to a viewing site. Fortunately planetary work can be done from even the most light polluted urban location. Good cameras for it are relatively inexpensive Flea 3 and several of the DMK cameras would be great for this. Still a 12.5" would offer much the same advantage (rarely does the atmosphere allow anything better) and far easier to lug around, still several times the work of your present scope.

Deep sky work however is very different. First and foremost is a good (thus expensive) mount. Without one no scope or camera can take a good deep sky image. Even an 80mm APO refractor would make a great imaging scope for this purpose and require a relatively inexpensive mount (about as far as your budget will go). Obviously the two, visual/planetary photography and deep sky photography require very different equipment when on a tight budget. The latter can be a large money sink. Cameras for planetary work are poor for deep sky work as they aren't designed for long exposures so get very noisy very quickly. Noise is not an issue with planetary work as planets are bright! DSO objects are very dim so down in the noise to start with. Most cameras cool to 30C or more below ambient temperature to help reduce this noise issue. Though some chips used in Canon DSLR's are fair even uncooled. Don't compare to a good cooled CCD but far cheaper so a good starting point. Especially when the IR filter is changed to one that doesn't block H alpha emission nebula. Of course deep sky cameras are poor for planetary work as they can't take many hundred images a minute.

As Redshifter says get to some star parties and help set up a large dob before deciding on one. They are a lot more work than the ads claim. As I mentioned most who jumped from your size scope to started out a ball of fire but after a few months the work became too much and most stopped bringing their big scope to star parties. Most left the hobby in fact though one returned with his 6" again saying he was just too old (45) for that big one any more. But we do go 30 miles to a dark site. Though he rarely uses the 18" at home either, just too much work when he can grab the 6" and be viewing in a couple minutes rather than moving everything in the garage so he can get the big one out, polar aligned and viewing then put it all away when dead tired. Those that went from 10" to 16" and larger survived nicely. Those from the smaller didn't.

It may work for you, but be sure to get some experience with such scopes before spending the money!


The scopes you mention LX90 and CPC are poorly mounted for deep sky imaging. They'd work for putting a DSLR atop the scope and letting its lens image the sky a constellation at a time but getting tracking accuracy for the scopes you mention needed for deep sky work through those scopes is very difficult. The CPC would possibly work with a AO unit to do the heavy work. Don't think anything can salvage the LX90 for this however. For that the LX200 is barely adequate and needs an AO for best results. All require a wedge for equatorial use.

I fought trying to use such mounts for years. I spent most of my time modifying them trying to get them to work with the needed accuracy. Backlash and sloppy bearings not noticed visually or for planetary imaging was virtually fatal in deep sky imaging. Why I never gave up I still can't fathom. After years of saving I bought for $9500 a really good mount and now am finally having a ball with deep sky imaging. It easily handles he 14" without a whimper. All my mount issues are gone and today the mount costs $5000 more so I could sell it at a profit but no way that will happen. Now I can worry about better scopes and cameras. Before they were unimportant.

A post just appeared on another forum that bears on DSO (not planetary) imaging.
http://www.cloudynights.com/ubbthreads/showflat.php/Cat/0/Number/4486438/page/0/view/collapsed/sb/5/o/all/fpart/1#Post4489146
Note #2 and #6 apply to the Dob and #6 does to all scopes you mention.

Rick

tteedd
2015-May-02, 08:41 PM
Hi Jeff

Not sure if you have a lot of experience but I have a 250p Flextube synscan so feel a little qualified to answer.

You said deep-sky, planets and astrophotograpy and some of the replies lean towards the third of these. However I started two years ago and might have said the same but I'm not into astrophotography yet and doubt if I will ever be. I am into visual and lately video astronomy and take the occasional picture, but processing is just not my thing. I want to do astronomy when the skies are clear and hate spending hours at the computer.

Visually the 400p is ideal for deep sky and good for planets. But it is a honking great thing and not at all easy to move around despite it's portable features. I do not move my 250p very much. If I could have afforded it though and a reduced price was available I would have bought a 400p but not for it's portable features. I would have bought it for its optics and aperture.

My advice is to join a society and go to exhibitions. I went to my first exhibition 2 years ago and bought a Skywatcher synscan 127 MAK. I bought it because it was reduced, because I had used one in Scotland (Galloway Astro centre is a great place to learn) and because it had the 'goto' feature.

I was lucky. It is the ideal scope for a beginner. No collimation, it finds the targets for you (but you have to learn a little of the sky to get started) and portable.
This scope like the other three I have bought has it's own problems (worst - unstable mount) as do the other three I have/do own/d, but I would recommend it.

If your end point really is astrophotography then you will probably eventually end up with an equatorial mount (I bought a cheap one on ebay just to learn about it but it does not get a lot of use).

Join a Society, go on an astronomy course under clear skies perhaps, but if you can afford it buy a cheap scope and trade it in when you decide what you really want.