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Newbie equipment questions.


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Hello all.

Further to my previous single post ( I asked about the differences between skywatcher and celestron 5" reflectors) I thought Id ask a few more questions since I want to get the best I can for the little money Ive got. Despite lurking for a while I still havent formed an absolutely concrete opinion on a scope, which is where I thought you guys could help me out.

My situation is currently this:

Im a penniless student with about £200 guaranteed and an undisclosed, barely discussed amount from parents (but as a ballpark, say about £150), who are probably going to fork over as an early christmas/birthday gift. Im not concerned with GOTOs seeing them as a cash sink that could be better spent on optics; and since I dont have a car a dobsonian or other massively clunky device is out. Storage space is also a bit of an interesting challenge. Ideally I'd like a bit of money left over for maintenance equipment if i need it (like collimation gear).

With this in mind, I've got a few questions.

1) Its apparently widely accepted that the budget entry into the field is a five inch reflector, but from what Ive seen of late in astronomy now and sky at night it seems that small maksutovs (celestron nexstars mainly) are starting to become more popular and more pushed by retailers. Is there any real advantage of the maksutov over a newtonian? I plan to observe a bit of everything; nebulae, planets and galaxies for visual interest and trying to find variable stars and other things for the scientific interest. Should I stick with a newtonian or go for a small mak?

2) In a similiar vein, I noticed the skywatcher 130PM has been discontinued recently, and this has caused a bit of an outcry. However what Ive been able to find out indicates that a spherical over a parabolic mirror at 5" of aperture isnt the end of the world that people think it is. OR is it?

I realise this is a challenge, and especially for ~£350, but I thought I'd throw down the gauntlet. Thanks for your help!

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There's a fair bit you can do with a budget of £350.00. One of the important thing to consider is that no telescope does it all so where something may be good at planets it may not be so good at galaxies etc. My first "proper" telescope was an 8" reflector on a dobsonian base, something like this:

Dobsonians - Skywatcher Skyliner 200P Dobsonian

This is a good size for hunting the M galaxies but as it doesn't track it was a bit annoying when it came to looking at planets - but then when you learn the techniques of moving a dob around then it does get easier.

With a tube dob you've also got the option of mounting it on an EQ mount sometime later. So if you're after an all round good and versatile scope I would recommend an 8" reflector on a Dobsonian mount - it's probably the best aperture for your money as well.

The down side is you would have to get to know the night sky so you could find the things you want to look at as dobs are not goto (unless you spend quite a bit more money). Learning the night sky can take quite some time but in the end it's worth it. The other downside, as mentioned before, is that you'll have to keep nudging the telescope to follow the object you're viewing - though you'll get used to doing this quite quickly. Hope that helps:)

Sam

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Is there any real advantage of the maksutov over a newtonian?

Not really in a practical sense and you could argue that a Mak isnt as good at least in terms of bang for the buck. A mak wont require collimation so its a bit more hardy but its also a lot more expensive.

Maks also need more in the way of anti-dew if conditions are tough. They usualy have a longer focal length so they work well on planets and often have a higher contrast gain over a reflector (though in a small scope this wont really show too much).

Most small Maks are supplied on a GoTo drive - even a tiny one like the Nexstar 4 will be more expensive by a long way over an equivalent refelector thansk to its GoTo set-up.

I have a Nextsar 4SE - I also used to have a Sky-Watcher 130PM and the 130 was a far more versatile scope - it was much more adept at DSO than the Nexstar for sure.

Should I stick with a newtonian or go for a small mak?

Unless space and portability are an overriding concern I'd go with the reflector - better views, more to see and a small reflector isnt THAT big.

I noticed the skywatcher 130PM has been discontinued recently, and this has caused a bit of an outcry. However what Ive been able to find out indicates that a spherical over a parabolic mirror at 5" of aperture isnt the end of the world that people think it is. OR is it?

A spherical mirror isn't a complete downer on a longer focal length scope like the 130 with the long tube. Its a disaster for a short tube though.

I think the outcry comes from the fact that the 130PM had such positive reviews and was, at the price, unbeatable. Lots of people have started their astro life with one as well and you'll hardly ever hear a bad word about it said.

The 130EM which is a kind of replacement has a longer tube and (from the pics) a not so sophiticated motor arrangement. I dont doubt it would be a good scope BUT......

With £250 to spend you could get a Sky-Watcher 150 on an EQ3-2 and they turn up regularly on ebay and on here. Dont forget though there will always be extras and upgrades (a dew shield, red light torch and a moon filter to start with).

The 150 on an EQ3-2 is a good combination - the long tube version is highly rated by lots of people. My sister has the short tube version which I like a lot myself.

The EQ3-2 would give you an EQ mount so you can track stars with the addition of a motor drive or even upgrade the whole shebang later to GoTo (though its expensive).

The other alternate would be a Dobsonian like the SW 200 - the 8" tube will give the best views of the lot.

Whatever you do avoid ebay - buy a decent brand because it will hold its value better but be VERY wary of ebay as I have seen people get bidding madness and bid way over the odds - your also potentially buying a scope from someone who may have cleaned the mirrors with a brillo pad at some point.

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I would say the reflector, simply for the better field of view. If you cannot get the object into view it kind of defeats the purpose. I have suffered this with a Mak.

One additional point a goto may be spending money on electronics but the use of motors to drive the scope while you are observing is very useful. Whatever you are looking at drifts out of view pretty quick, getting it back to the centre by use of left/right/up/down commands to a set of motors makes it pleasant.

The last time I used my goto I simply pointed at the target, got it in the field of view (eventually+luck) then tracked it manually. Yes you can track it manually but it has to be more difficult.

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A lot of love for the 150P I see. Having had a gander Im very tempted by it, too. Im still a bit confused with the difference between the two.

What I mean by that is that I understand that one is longer than the other, longer focal length and hence more magnification and contrast; but doesnt that mean that essentially Id end up looking at a slightly larger coloured blob? Which version should I go for if assuming I primarily look at deep sky objects?

Scope aside, are there any other accessories I should be looking for besides a moon filter, collimation aid, LP filter(?) and a red pen torch?

Also, blumming hell at an EQ3 motor drive! £75 compared to the EQ2 which is about £30. I understand that its got to swing a larger mass around, but its still a fair chunk of money. :/

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Yeah the addon on motors are a total rip off, but are rather essential if you want to image, and very handy just for visual too. If I remember my F numbers correctly the shorter tube 150 will suit DSO work somewhat better, but will be a little more sensitive to collimation issues and will be more picky on what eyepieces it gets on with. I went for the 150PL as it's a mid range speed, and being new to the hobby I didn't know whether I'd like planetary or DSO work... Since getting the imaging bug I've picked up a nice fast refractor ;)

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