Pleeeeaase Help!(choose a telescope)

[tinny]

Hi guys,

I'm sorry to ask this question as I guess every beginner who passes through this hallowed lounge does the same (again and again)!To cut a long story short after about 2 months research and self control I have narrowed the choice down to two - the celestron Nexstar 6SE or Skywatcher Explorer 200p (with or without GOTO or Syntrek?)

As I am lucky enough have a cottage on the East coast and one in the lake district, both hopefully good dark sky locations, I guess portability is an issue...Both these 'scopes are around the max I am willing to pay for my first.

Please help me choose or suggest something new...any help will be gratefully recieved

thanks again

tinny

[Bizibilder]

If you want portability and ease of use then maybe you should consider a Dobsonian (This is a Newtonian telescope on a very simple mount called after its inventor hence Dobsonian). You just plonk it down and away you go! The downside (there has to be one!) is that it is not suitable for astro photography, even if you go for a motorised verion. The upside is you get the greatest aparture for your money - good for faint Deep Sky Objects and the motor driven / goto ones are perfectly suited for visual observing.

Now that I've confused you.....over to the next poster..

[umadog]

I agree with Biz, can't go wrong with a good 8" Dobsonian and a Telrad. Portable and cheap. If you have dark skies then you'll find star-hopping easier than those in the city. The requirement for GoTo is therefore lessened. In fact, if the skies are really dark then the brightest deep space objects are visible naked eye: just point the scope and off you go! Just get yourself a nice guide book such as Turn Left at Orion.

[tinny]

Thanks Bizi

I've just been having a look at those, that monster aperture is tempting...I guess if I can find the conditions to match it! I didn't realise that their un-suitability for astro photography though, I'm already planning to do some so thanks for the tip...Hmmmmmm guess its back to the drawing board!

Cheers mate

[umadog]

You won't be doing much photography with a small budget. Also, photography is substantially more involved than visual observing. It's probably better to stick to visual, learn the sky, then go into photography if you're still keen on the idea.

[tinny]

Hi Umadog

Nice dog by the way!So are my two original choices are pretty crappy!!?Pls excuse my ignorance but what is a Telrad?And is it possible to use a dob when I'm back at my main home which is a little light polluted...sorry for all the questions

p.s. got an early start tommorow so may drift off!

[tinny]

That sound like like some common sense thanks umadog

[PhoenixRising]

Nothing wrong at all with the 200P, its a great all-round scope. Just not very portable.

[umadog]

Exactly, nothing wrong with the scopes you mentioned. It's just that an 8" Dob is a good general purpose beginner scope: decent aperture, portable, quick to set up, easy to use, and cheap. You will have more cash left over for stuff like eyepieces, light pollution, filters, and books. It's not just about telescope, so don't sink all your cash into it. There are, of course, a variety of good scopes and different people have different requirements which may make one design better than another.

A Telrad is a so-called zero-power finder. You look through it and it projects three concentric rings into the sky. Shows you where the scope is pointing. This is the easiest way of pointing a telescope. You use naked eye stars as a reference to do this. So if the area has little light pollution there are a lot of reference stars. This way the target will either be in the eyepiece or not far off. This is called star-hopping. You can also star-hop short distances by looking through a low-power eyepiece or finder-scope, but usually this isn't necessary.

If you learn the constellations and star-hop then you'll become intimately acquainted with the sky. This is nice, but of course there's more learning involved and your first few outings may be a little slow. It's not at all hard when you get the hang of it. If you're the sort of person who would rather just look and have a machine do the work, then you should think about GoTo or Push-To.

All scopes work less well in light polluted areas. It won't influence your scope choice hugely, I'd say. If it's very light polluted then it can be hard to find stuff as not many stars are visible. Orion Dobs have an object locator which helps with this (Inteliscope series of telescopes). Then again, if the light pollution is so extreme and you have better options, then I'd take those options and not fight the light pollution. You may find the objects with the locator but they won't look very good through all that orange haze.

[hemihaggis]

127 mak is best ......... tell him about collaminating a dob every time you use it !!!!

[jamespels]

I wouldn't worry too much about a dob not being suitable for astrophotography - any solid tubed dob can be pretty easily remounted on an equatorial mount when you have the time and inclination (and funds - an 8" newt is going to need an EQ6 at least - these cost about a grand at the moment). Also, an unguided dob will still be fine for lunar photography and there is freebie software online that can rotate stacked images so planetary photography is perfectly feasible, too (the standard method is to record an AVI using a web cam, ditch the lousy frames and stack the rest. A dob can track objects in the sky but moves about the wrong axis so the image will rotate; AVI frames will obviously not stack correctly if the last ones are several degrees out from the first ones).

Collimation is a pain, yes, but not too bad. I am very fortunate to have a Newt that holds collimation well so I am by no means an expert at it but it should't take more than 5 minutes when you have got the hang of it (once you have the secondary mirror right, it will rarely go off unless you belt it so most day-to-day collimation will be minor adjustments to the primary).

[umadog]

What Haggis is saying is that you need to make sure a Newtonian is aligned before using it. On a solid tube this will usually amount to a quick check and maybe a tweak. You see a lot of threads on collimation and this may lead you to believe that it's difficult and scary. In fact, for most people it's easier than they think. In practice, collimating a Newtonian is a non-issue. It will take you under 5 minutes once you know what you're doing. Under 2 minutes if it just needs a tweak. The couple of minutes are worth the payoff for a Dob's advantages.

[Damo636]

127 mak is best ......... tell him about collaminating a dob every time you use it !!!!

Sorry, but this is simply incorrect. The 200p dob holds collimation extremely well unless it is very roughly handled. It's weeks since i had to tweak mine and its in and out of the shed at every opportunity. Don't let collimation put you off buying a reflector, its as simple as tying your shoe laces once you do it a few times and takes no more than 5 minutes if minor adjustments are required.

[Bizibilder]

I agree - unless you really bash a scope it should retain collimation for quite a while. My own 200P lives, off the mount, standing upright on the collimation screws/locking screws - no problems.

If light pollution is a problem then you can use a light pollution filter. These are fine for getting rid of the dreaded "orange glow" of sodium street lights.

[hemihaggis]

What Haggis is saying is that you need to make sure a Newtonian is aligned before using it. On a solid tube this will usually amount to a quick check and maybe a tweak. You see a lot of threads on collimation and this may lead you to believe that it's difficult and scary. In fact, for most people it's easier than they think. In practice, collimating a Newtonian is a non-issue. It will take you under 5 minutes once you know what you're doing. Under 2 minutes if it just needs a tweak. The couple of minutes are worth the payoff for a Dob's advantages.

dont worry i ahve a newt also !!! they are great design of scope

[tinny]

Hi just got in from work!

Thanks for all this help and advice i really appreciate it...this has got to be the nicest (lounge) I had the fortune to visit!

So I've decided to do it properley...the skies are dark enough to learn the sky without GOTO and thanks to your fantastic advice I think I'm going for a dob...I want to spend £800 max which I see is plenty but to my un-trained eye all the makes look so similar I'm a bit confused, except I really like the look of the fold down (flexi-tube?) ones to take with me...

Can anyone make a recommendation to make, aperture etc?

Thanks again you've all been brilliant, my first star party your there!

[jamespels]

I would avoid flextubes if you are thinking of using the OTA for astrophotgraphy later on - you will never get it to sit right on anything other than a dob mount. Assuming this is what you want to do, the 200P dob is probably going to be your best bet - newts get BIG as the aperture goes above 8" and I doubt you will get anything bigger across the back seat. Personally, I would go for the 200P dob, spend some more of the budget on a few hand chosen, high quality eye pieces and save anything left over towards an EQ mount later on.

Alternatively, you may want to go for a flextube (any size really, but they get very heavy from about 16" so think about lifting them the car, etc.). Then you can think about a lovely 100mm APO refractor for photography later on if the mood takes you and you stiull have a lot of cash burning a hole in your pocket .

[umadog]

Both an 8" and a 10" will fit across your back seat. The 10" scopes you see tend to have focal ratios below f/5 so they aren't much longer (if at all) than an 8". I tend to steer beginners towards f6 and faster Newts as a first scope, simply because they produce nicer star images with non-expensive eyepieces and because the collimation tolerances are less stringent. The 8" will probably be f/6 the 10" will be below f/5. Perhaps more chance of a good mirror at f/6 as these are easier to make, but who knows? At the end of the day, either is probably a fine choice. A 12" scope is substantially more bulky than a 10". The two inches separating any neighbouring pair of apertures don't make a a vast difference to the views so let convenience and portability guide you as much as aperture.

Optically, all these mass-produced Dobs are likely to be very similar in quality. I think they will all be made by either made by Synta or GSO. IIRC, both of those are Chinese. Sky-watcher, for instance, is Synta (IIRC). The optics coming out of China are now pretty good and it's unlikely you will get a lemon, particularly in the smaller apertures which are easier to make. The differences you should look out for are things like focusers (If you go for faster than f/6, it's nice to have a dual-speed focuser) and azimuth/elevation bearings. Look around on the net to see which of your choices is said to have good bearings. You can always upgrade the bearings yourself later. But if you check first you won't have to do this. I used to have an Orion XX12 inteliscope and that had pretty good bearings and adjustable tension in elevation. Presumably the same is true of the smaller apertures. The inteliscopes are expensive, though, as you're paying for the electronic gizmo which you may or may not want. I know that the basic 8" Dob from Orion has horrible bearings but, as I say, you can fix that pretty easily. Contact Beacon Hill Telescopes for advice on this if needed.

[tinny]

Brilliant I guess its now up to me to have a look around to see which catches my eye...

I think you guys have helped me whittle it down to a 10 " dob and an after market set of quality eye pieces to complement it. I want to learn the sky the old scool way, I can't wait to find my planet, cluster etc so no GOTO for me, anyway it seems a waste not to spend it on the scope!Thanks for the earlier tip on "Turn left at orion"(!) Uma, its already on its way. And James your right, I can learn the sky and get some real astro photo tech when I'm ready for it...

Wow btw I just went outside and the sky looks amazing

Time for beddy byes tho haha thanks so much all of you

[ronin]

My advice: Get one of the ones you originally wanted.

They came out as the primary choice then and were so for a reason I suspect, as in they fitted your requirements.

[tinny]

Haha thanks ronin, although I was making that decision based on exactly zero knowledge!I'm afraid I'm still a little unsure...