First Scope

[pediman]

Hi

I'm sure that this has been done to death but am in need of some advice.

I'm looking to buy my first scope but the range available is so huge!!

Want to get a good look at the planets initially but also want to see some stars further afield.

Are there any scopes that do both well??

I don't want to spend a fortune initially but also don't want to have to keep upgrading.

I thought of maybe a Dobsonian as they seem good value for money, but would this be too much for the planets?

Anybody out there who can help??

Cheers,

Matt

[Ben Ritchie]

Any interest in imaging, or are you just looking for visual use?

For visual, a dobsonian gives the most aperture for your money and will be excellent for both the moon/planets and deep-sky objects. It's worth remembering to budget for some eyepieces too though, they can get expensive but don't have to be.

[pediman]

Just visual use to start with.

Have had a look at some of the goto scopes, but want to try and find my own way around the sky.

I'm pretty lazy so if i had a goto scope i don't think i'd learn very much, i'd just let the scope do the work.

Would at a push be able to spend £500, so am looking at the best i can get for that money.

[themos]

The Skywatcher Skyliner 250PX (£339) + a TeleVue Nagler for wide field + an orthoscopic for planets?

[Doc]

The 250P dob is a fantastic scope and will show you all you could ever want to see.

http://www.firstlightoptics.com/proddetail.php?prod=dobsky250px

As for eyepieces, these can range form £30 to £500. As you are just starting out how about a set from Celestron. Not perfect but will give you a full set and a barlow. It's a good start to astronomy.

http://www.firstlightoptics.com/proddetail.php?prod=CelestronEPkit

[jamieren]

I was in your position not long ago, ped. I would say the most important thing to consider (recollecting from myself) is really how long & how much your desire for astronomy has persisted. As a kid I loved the idea -but am glad it wasn't ruined for me by a cheap telescope. Throughout my youth and young adult years it had always been on the back burner somewhere (sometimes forgotten for years). Finally I took the plunge; and after a few meager sessions with some 7x50 binocs bought an 8" dob. At that point I knew this was something I would stick with for sure (but had suspected that all along.. as you may be in the same boat).

The retailer I dealt with then put a 12" on sale. Oh the agony! As soon as I found out it would fit in my van it was sold. This was a two sided decision I'm now finding out. I still use it regularly but do miss the easy portability of the 8" (mount & all were easy to pick up and put in my van, not so with the 12 which needs to be disassembled).

My point is (a big sigh of relief goes here I'm sure :laughing9: ) you'll know how serious you are about this from the start. I don't necessarily disagree with themos, the 250PX would be a magnificent choice. One thing I will strongly recommend is that you get a book if you're going to do it without goto. Nightwatch was the one I got by Terrence Dickinson and it was perfectly suited to my needs - lots of newbie intensive training and detailed star charts to carry you from there.

So glad to see another new guy posting here, you'll soon find out the advice & people here are second to none. Good luck, hope to see more posts from you soon!

Jamie

[scotastro]

Reflectors give the best flexibility for observing the planets, nebula and galaxies, etc. Planets require high magnification (150x and more) to see detail, but deep sky objects need less magnification (200x or lower), but also light gathering ability - so the increase in aperture.

An 8" dob in good skies will show huge amount - yes 10" and 12" are even better - but oh the weight penalty. Jamie made a very good point here.

It is easy to get carried away with big aperatures forgetting how much the weight increases with only a relatively small increase in diameter.

A dob can be fitted with wheels (see posts elsewhere) for easy moving unless you are going up and down stairs.

Unless you are very anxious to get a scope right now, why not take up Paul's offer (see his Welcome post) and see some scopes in action with the CSOG.

Mike

[pediman]

Thanks to you all for the helpful comments.

I will certainly get in touch with Paul to have a try before taking the plunge.

I've been looking with interest at the new Skyliner flextube dobs.

Maybe the smallest 8" one. They seem to be more portable and easier to manage, so would hopefully mean it gets used more.

Does anybody have experience of these?

One thing worried me, which is do you have to keep collimating the mirrors everytime you set it up?

Matt

[Doc]

Solid tubes hold collimation very well.

Flexi tubes are not bad if it stays assembled.

If you strip it down after every session then yes it's needs collimation everytime.

I have a truss dob and leave it assembled but it still needs a very small tweak with the laser before every session.

It sounds daunting but the more you do it it becomes simple and quick

[pediman]

Yeah,

Think itmay be better to go for the 8" solid tube version.

Over £100 cheaper and i can use the money for some good eye pieces.

Any ideas on which eyepieces to get??

Matt

[kniclander]

you'll get a 10mm and a 25 with the scope given 120 and 48x. Might be worth seeing how you get on with those first as the 25 mm is ok and you might not feel the need to replace it. You'll probably want an alternate higher power e/p as the 10mm isn't great and you might want something a bit stronger but with a dob, (obviously) the higher the mag the more you have to push the scope around. You'll get used to this but I find it too much of a pain at high mags. i find 8mm is the shortest eyepiece I tend to use (except for occasional dble star splitting) as with anything shorter the object is only in the fov for a few seconds.

good luck

Dan

[jamieren]

Yeah,

Think itmay be better to go for the 8" solid tube version.

Over £100 cheaper and i can use the money for some good eye pieces.

Any ideas on which eyepieces to get??

Matt

I'd agree with you here, Matt. That dob (just guessing) won't weigh more than 40-50lbs. Unless you're way out of shape or have severe back problems it'll be no problem to manage. I realize you were referring to truss-dobs but as to collimation issues don't be too worried. I find my 12" has only really needed collimation once. It's been checked twice since I originally collimated it and has not needed any serious adjustment (none at all TBH).

As Dan says "..you'll get a 10mm and a 25 with the scope given 120 and 48x. Might be worth seeing how you get on with those first.." maybe try out the starter EPs. There's a great variety in 'upgrades' and it might be worth it to find out what works for your viewing style.

One thing that was missed in my pre-purchase studies was the f/ratio. This is found by dividing focal length by aperture.. in my case 1500mm÷304mm=approx. f/4.9. I've learned that in 'faster' scopes (lower f/ratio #s) it is more difficult for an eyepiece to deliver a sharp view all the way across the field. The rule of thumb for this is f/5 and less. That is to say in a low f/ratio scope you could be spending more on eyepieces to get nice views, as they tend to be pickier I am told. Either that or a lot of people I talk to own shares in Televue and Pentax.

[dogfish]

Hi Matt

If you've not played with many scopes previously, why not wait until the next CSOG outing. Then, if you come along, you can have a play, look through, and get some idea of the technical issues involved with an array of scopes. There are dobs, SCT's, equatorially mounted Newts and some refractors too.

To find out when the next outing is email G1zmo and get put on the mailing list. One of our sites is not very far from Livingstone, mind you, we'll have to wait for the weather to play ball.

Cheers, Martin