5" GoTo.. or 6" EQ mount?

[Macman]

I have about £300 budget to spend on a good quality starter scope. I am tempted to get a 5.1" GoTo which can point me to the right locations easily.... OR should I get a 6" Equatorial Mounted scope (non-computerised)? I am a novice when it comes to finding the right star/deep sky object but I want to have the maximum light gathering scope possible. I just don't want to be disappointed if I cannot find the object I am looking for, where a GoTo would (pretty much) guide me there at a click of a button.

I want to be able to view as much as I can in my time stargazing, but I also want to be able to see as much as possible from a light gathering point of view. What advantage does a 6" scope have over a 5" scope in term of what it can/cannot see? ie, would the 5" scope be able to pick out individual stars in the Hercules globular cluster M13?

I just want to make sure I purchase what's right for me.

Thanks

[Mikea]

Theoretically, 6" gives you about 44% more light gathering area, so should permit viewing of lower mag objects. My light polluted sky and EP's that came with my 5" Newt don't let me split the stars in M13, although many other clusters are just as impressive (Eg Double Cluster in Perseus). Whether you have GOTO or star hop your way around is purely personal choice. There are probably equal numbers of pros and cons for each camp. If it's really DSO's your after, you could get an 8" Dob for less than £300. Wait for all the responses to come - there will be many opinions!!

[ollypenrice]

In astronomy terms £300 is not a great deal of money. In my view it would be better spent on the optics than on the Go To because the Go To cannot do anything your brain can't do while the optics CAN do things your eyes can't do.

Also, be aware that there are many anguished and frustrated posts on this forum from people who find their Go To will not behave itself - perhaps because they don't understand it or perhaps because it is another IT based product that doesn't do what it says it will. (You may just have come across one or two of these in life already!)

I would go for an 8 inch Dob with real light grasp and a mount that will help you learn the sky. It is not that difficult!

Learn the sky and see things for real when you have found them; that's a win-win arrangement as far as I can see.

Olly

[twotter]

I've recently got one of these (Dobsonians - Skywatcher Skyliner 200P Dobsonian) and it is easy to use and has given me some lovely views. Using a combination of Stellarium, Turn Left at Orion and a Philips star map I make a note of my 'targets' for the evening and how to find them. Then I'm outside and star hop away

[steve_bham]

I have a goto 6" scope and having the goto is great if you only have a few hours here and there to pop out and want to get the most of your time. The good thing about having the goto mount, is if you dont want to use the goto facility then you can still find objects manually.

I find the goto is helping me learn the night sky as well. Ive never had any problems with, if you spend an extra 5 mins setting it up then you wont have any problems.

Steve

[Bizibilder]

Buy the bigger optics with your £300. You can always save up more pennies while you are learning your way around and then upgrade to fancy computers etc. If you buy a small scope now you will forever want to buy a bigger one!!!!!

By bigger I would suggest 200 or 250mm reflector or Dobsonian.

It does not take long to get used to the sky AND to point the scope in the right place! This has the added bonus that you are learning the sky at the same time.

[brianb]

At the £300 level it's a mistake to invest in electronics over optics. Goto is IMO a desireable shortcut for the dedicated amateur who knows his or her way around, not a substitute for learning the sky. If the electronics are adding £150 to the package price (and that seems a reasonable estimate) then your £300 is buying you twice as much scope if you do without it ... that will show considerably more, even if the only reason is that the mount is steadier (most of the cheaper goto scopes are distinctly wobbly).

[arad85]

I'd echo what's been said here. Biggest dob you can afford/manage. I have a CG5 with either a 80ED or C9.25 SCT on it. It takes a while to setup, but the 12" dob is outside in minutes, and barring cooldown, has no setup time whatsoever. You'll soon learn where the interesting objects are with a decent star map (I have the Sky & Telescope one which is great) and a little bit of time. I personaly think it's also worth investing in a telrad finder as it really does help you figure out how far to jump as the projections are 0.5, 2 and 4 degrees (IIRC).

[steve_bham]

While i echo the statement "buy the biggest optics you can afford" you will also have to think about moving the scope. if its just too big it wont get used as much as a smaller one.

So yes buy the biggest optics and you are happy to move around.

[Macman]

There are some brilliant answers - thank you all very much. It really has made me think now! An 8" dobsonian sounds perefct, if a little on the 'difficult to move' side, but I would only be taking it from the house into the back garden - i don't intend to drive anywhere with it.

Do Dobsonians have an EQ mount - or are they Altazimuth only? I currently have a basic 'don't buy from a camera shop' 3" refractor which isn't perfect. It's pretty unstable, and, if i'm lucky, I can just about see the belts on Jupiter with some severe eye-straining.

I want a telescope that will take me WELL into the next level. I want to see the outer planets, i want to see detail, i want to see galaxies and deep sky objects (albeit fuzzy) that my 3" couldn't dream of. But i do get frustrated at the 'is that the right star?' or 'Where did that planet go?' as stars slip out of view every few seconds when I look through my 3".

Would a Dobsonian do this better than other reflectors? if so - why are they costing the same as smaller EQ mounts?

Sorry for the questions! I am a novice!!!

Thanks

[Bizibilder]

A Dobson is Altazimuth. You can upgrade to your hearts content later! Don't forget yiou will need to factor in the cost of a power supply as well (12v battery type NOT mains!!)

You WILL see the outer planets, galaxies and DSO's BUT they won't look anything like the photo's you see!! These are all LOOOOOONG time exposures - often several "stacked" together over several nights! - you will see "fuzzies". Many star clusters are superb in an 8".

[John]

The term "Dobsonian" refers to a newtonian scope which is mounted on a simple up / down (altazimuth) mount. The concept was pioneered by a guy called John Dobson - hence the name.

In essence you simply point it to where you want to look. You do need to gently "nudge" the scope to track objects at higher magnification and the mount can't be used for anything but the most simple astro-photography (imaging as it tends to be called).

So with a Dobsonian what you pay for are the optics and therefore you get your biggest "bang for your buck" ie: obsering potential, with this type of scope.

An 8" scope will move you firmly into "the next level" wheras a 5", in my opinion, won't be such a big step - you will want to move on pretty quickly if your interest in the hobby holds.

I use a 12" dobsonian which I can move quickly and relativeyl easily (in 2 parts) into the garden for use.

You will need to be prepared to find your own way around the sky but, for many, this is a great part of the enjoyment.

While a GOTO mount will find things and put them in the eyepiece, theres not much point in that if you have not got enough aperture to do the object justice !.

John

[adamsp123]

A Dobsonian is a Newtonian reflector on a very basic and hence cheap mount so the money you spend goes into getting larger size mirrors, if you go for GEM mounts then some of your money goes towards the more complex mount and hence you end up with a smaller aperture scope for a given price.

I love goto mounts, I firmly believe you can learn an aweful lot of the night sky using one properly, and correctly set up the gotos are such a time saver, but this comes at a high cost.

In your shoes I would go for a Dob plus the book "turn left at orion" and download the free software Stellarium.

Pete

[geoff_k]

Leave the go-to for later and get the best optics. Go-to is great and as already said, a real time saver given our unforgiving climate, but at the beginning it just complicates matters.

Whatever you get, enjoy it!

Geoff

[resonator77]

I think many people forgot to mention the benefits of a go to in comparison to Dobsonian. Most of the computerized telescopes (Go to) are very good for tracking objects in the solar system. So if you plan to view Jupiter or any other solar system planets then you have to move your telescope manually, which is a bit tricky. I find Go to very handy due to its tracking and touch of a button object finder capabilities.

Resonator

[John]

I think many people forgot to mention the benefits of a go to in comparison to Dobsonian. Most of the computerized telescopes (Go to) are very good for tracking objects in the solar system. So if you plan to view Jupiter or any other solar system planets then you have to move your telescope manually, which is a bit tricky. I find Go to very handy due to its tracking and touch of a button object finder capabilities.

Resonator

Absolutely right

But you want a decent aperture as well and that's hard to achieve for a £300 budget.

John

[coffee_prince]

First light optics are selling an 8 inch newt on cg5 for only £289. I have one reserved as my first scope. I'd pick aperture over a goto with smaller aperture.

I tell you this because it is literally the best offer on the internet that I have found, and has the option of upgrading to dual motors or goto's at a later date.

It comes with only one plossl though, so i am having the agonising issue of deciding what accessories to buy with it.

All the best

[Macman]

Thank again. A couple more quick questions I hope can be answered!

1. With a GoTo - how long do the batteries realistically last? And do re-chargeable batteries work ok?

2. With a Dobsonian - are they easy to slew and are they stable once an object is in vision? Also, what care does a Dobsonian need? ie, regular collimation, etc

Thanks!

[John]

A couple of quick replies for you !.

1. GOTO's don't work well on batteries - use a Powertank.

2. yes and yes. I was using my 12" dob on Jupiter at 250x last night. Carewise they are the same as any newtonian scope - you will need to know about collimation but an F/6 won't be as fussy as an F/5.

John

[Bizibilder]

Don't forget a cheap powersupply will eat up £50 of your budget BEFORE you buy your scope and mount - leaves you with £250 to spend!!

Follow the advice - buy good optics and then upgrade as funds allow.

[resonator77]

Thank again. A couple more quick questions I hope can be answered!

1. With a GoTo - how long do the batteries realistically last? And do re-chargeable batteries work ok?

2. With a Dobsonian - are they easy to slew and are they stable once an object is in vision? Also, what care does a Dobsonian need? ie, regular collimation, etc

Thanks!

My Go to Nexstar is on rechargeable batteries, although I have got powertank just in case:). Seems to work fine with batteries as well. If you are planning to buy rechargeable batteries, I advice you to get Energizer, they seem to last longer than Duracell.

[themos]

You can just about bag a 12" Dob second hand for £300.

[ashdown]

Sorry about the silly question, but I've been wondering....

Do Dobsonians typically sit on the ground or are they mounted on a tripod? I ask because they always seem to be pictured without anything underneath them, as in FLOs page: Dobsonians - Skywatcher Skyliner 200P Dobsonian.

[themos]

There is a round base (pizza-shaped!) and there's three rubber feet underneath. No tripod.

[coffee_prince]

i'd like to know where you can buy a second hand dob for 300