Help on buying my new scope

[brascoe]

ive got a budget of £400 - £500 not sure what to buy there is so much on the market its making my head spin. I dont want to get into astrophotography just yet i will do but at a later date. At the moment i just wanna see as much as my eyes can take in. I dont want to buy any accessories with the money as ive got seperate money for that. All your help would be appreciated

[hemihaggis]

hi there , if i was you i would go along to my local astro club and chat to the folk there , find out which type of scope/setup you think will suit you best .

[swamp thing]

A 6" or an 8" Dob will serve any beginner well and give a good account of itself on nearly all objects.

If a desire to take pictures comes along the OTA can always be put on a GEM later.

That's my advice.

Regards Steve

[umadog]

That's a reasonable budget. You need to consider where you'll be using the scope. Will you be transporting it to an observing site? Do you have a car?

One decision is whether to pay for electronics. Personally, I favour greater aperture and no gizmos over smaller aperture with goto or an object locator. I feel the electronics get in the way (although I do have one scope with that stuff, the rest are definitely staying gizmo-free). Making that choice is one way of pruning down your options.

An 8" or 10" Dobsonian would make a great starting telescope. I am slightly more in favour of the 8", since they are about f/6 and so more tolerant of small collimation errors and produce nicer star images than the 10" <f/5 scopes.

[saturn4me]

Blimey.Even minefields aren't as confusing as this astronomy lark are they? lol:D.Im new to astronomy and it seems like im taking in all the worlds knowledge.Theres so much to learn:o

[umadog]

Ah, but learning is part of the fun! This is a learning-based hobby, after all.

[saturn4me]

Ah, but learning is part of the fun! This is a learning-based hobby, after all.

It certainly is and im loving reading all the threads on here.My wife thinks ive gone mad:rolleyes:. I think like every beginner i want to know whats what in no time. Silly really:o. Still, im enjoying the learning process though:D

[umadog]

Good stuff!

[brascoe]

Its all good fun and sites like this make it so much easier for us beginners and its good that there are ppl in the same boat. So the 8" dob is better than the 10" dob for viewing planets?

[onesmallstep]

The 8" will be slightly more portable for taking to site and/or setting up and taking down. The 10" has more light grasp and will show more detail (more light to play with). However at f5 and f6 both scope are pretty similar so you shouldn't notice that much difference as so many other factors influence the capabilities of any scope such as seeing conditions, eyepieces, light pollution.

[Matt2011]

Hello and welcome to Stargazers Lounge, I would seriously recommend the Skywatcher 127 Skymax Auto Track Maksutov Telescope and its what I have and its portable and its £329.00 or may have come down in price but he reviews are gr8 and the planets and the moon are absolutely breathtaking with this scope and you cannot go wrong with this scope and you can buy it from First Light Optics.Com or Pulsar Optics.Com but its awesome quality for the money:) Good Luck:)

[umadog]

The 8" and the 10" should be pretty similar on most counts, including planetary views. Planetary views are limited by atmospheric turbulence (the so-called "seeing"). Generally, those scopes are capable of delivering more resolution than the atmosphere allows. Similarly, light pollution affects all apertures equally.

You'll soon find that everything's a compromise. A 10" gains you more light but you'll also see more coma (distortion at the edges of the field of view) with an f/5 scope (the 10") compared to an f/6 scope (the 8"). IIRC the severity of the coma is inversely proportional to the square of the focal ratio, so there is a significant difference between f/6 and f/5. Manufacturers make their 10" scopes about f/4.7 to f/5.0 in order to keep the tube length fairly short. Buyers like that because it allows the scope to easily fit into a small car.

My reason for bringing up the focal ratio isn't that it's a really big deal, but that it's often neglected when a beginner chooses a scope even though it is worth consideration. This is particularly the case between 8" and 10" scopes where the difference in light-gathering isn't huge, so focal ratio is just as much a consideration as aperture. It's a personal choice, but some guys prefer f/6 and above because the stars look nicer. Also, slower focal ratios are more forgiving of poorly designed eyepieces. So you will see less astigmatism at f/6. This isn't a consideration if you buy reasonably nice eyepieces, however. Finally, the coma will only noticeable at lower powers so it interferes little with your views of planets and most DSOs. Open clusters are the main consideration.

[ollypenrice]

The other factor is focal length. Long FL scopes have a smaller field of view than short FL ones in a given eyepiece, and having a wide view can be nice, especially when starting out.

Below you see the Pleiades cluster framed in an 8 inch F5 scope and 26mm Plossl eyepiece. The circle to the right shows what the 127mm Maksutov would show you in the same eyepiece. Not better or worse but different. (The circles would not appear to be different sizes in the eyepiece, they would be the same size, so the Mak would be giving more magnification.)

Olly

[brascoe]

Blimey.Even minefields aren't as confusing as this astronomy lark are they? lol:D.Im new to astronomy and it seems like im taking in all the worlds knowledge.Theres so much to learn:o

I know tell me about it will it ever get easier. Sorry for maybe being a little slow so what your saying is depending on the scope you will get a different viewing field. So as far as between the 8" and 10" although you get to see more in the 10" with the right accessories and conditions a 8" makes the view a little neater. Is this right ? So big is not always best so to speak

[brascoe]

That's a reasonable budget. You need to consider where you'll be using the scope. Will you be transporting it to an observing site? Do you have a car?

Transportation isnta problem as i have a vw transporter and im a pretty fit guy so weight etc isnt a problem

[umadog]

Then you'd have no trouble whatsoever with a 10" solid tube. I'm sure you could manage bigger, but then it will break the budget. Furthermore, I'd argue it's important for your first scope to be something you'll find quick and easy to set up. If it's too big, whilst you may still be able to "manage it", you will inevitably use it less.

[ollypenrice]

I know tell me about it will it ever get easier. Sorry for maybe being a little slow so what your saying is depending on the scope you will get a different viewing field. So as far as between the 8" and 10" although you get to see more in the 10" with the right accessories and conditions a 8" makes the view a little neater. Is this right ? So big is not always best so to speak

The magnification is worked out by dividing the focal length of the telescope by the focal length of the eyepice.

1000mm focal length scope with 25mm EP gives 40x.

1250mm focal length scope with 25mm EP gives 50x.

This means that the higher maginifcation 'zooms you in' a bit, reducing the field of view but increasing the detail. Better or worse depends on what you're looking at. It is exactly like the zoom on your camera. You go for the best way to 'frame' your target.

Olly

[x6gas]

A really important factor is ease of use. Dobs are a very basic mount, quick and easy to set up and as already mentioned because the mount is so basic more of your money goes on aperture than an equivalently priced GEM mounted Newtonian reflector.

However, that's not the only consideration. I like to tinker and I enjoy things like collimating the scope, setting up my GEM and trying to get the most out of it. I have also enjoyed dabbling in deep-sky imaging and while my mount isn't really good enough, I have learnt the basic principles and satisfied myself that I am interested enough to purchase a better mount at some point in the future.

For me, a Celestron C6-ngt goto was the perfect starter scope, but that won't be true for everyone...

[Dave-Ryan]

Most people, eventually, find that one telescope isn't enough as each telescopes has strengths and weaknesses making that scope more suited to a certain aspect of astronomy.

Long focal length telescopes are better for viewing solar system objects, such as planets and small deep sky objects. The shorter focal length scopes give better wide field views which are needed to fully frame some of the larger deep sky objects. This really comes into play with astrophotography.

[brascoe]

Most people, eventually, find that one telescope isn't enough as each telescopes has strengths and weaknesses making that scope more suited to a certain aspect of astronomy.

Long focal length telescopes are better for viewing solar system objects, such as planets and small deep sky objects. The shorter focal length scopes give better wide field views which are needed to fully frame some of the larger deep sky objects. This really comes into play with astrophotography.

Thats what im thinking now maybe get two scopes eventually last night was we had clear skies down here so i thought i would drive to the edge of the village where there is a field nearest light is about half a mile or so away. Boy did i see alot of stars so newt time im gonna go to the new forest where there isnt any light pollution for a few miles i can only imagine how many there will be. Anyway this got me thinking maybe i sholud get a goto to start or will this make me a lazy astronomer maybe im thinking a new thread lol