Which scope to buy with group use in mind?

[TheQuietEarth]

Hi,

I've got a budget of £350-375 and want to purchase a GoTo telescope that I can use with others (kids and other family members). I'm new to this and I currently don't know how to star hop and/or locate non-obvious targets in the night sky. We'll be driving to darkish sky sites outside of Glasgow and we'd like to be able to set the scope up quickly, find objects easily and share the views with one another.

I've been doing quite a lot of reading about the subject and have narrowed it down to the Celestron Nexstar 130 or 127 SLT. I'm also aware of the 4se and its better mounting system but I think I'm unsure if it's worth sacrificing aperture for the sake of a better mount and slightly better internal optics.

I'm leaning more towards the 130 SLT as it seems to be slightly more versatile and will allow us all to see deeper objects slightly better, whereas the 127 will, out of the box and without buying new eye pieces, show crisper and closer views of the moon, Jupiter and Saturn compared to the 130.

How different will the views of the planets and moon be between the 127 Mak be compared to the 130 Newtonian Reflector? Will I need to purchase a better quality eye piece to get closer views of the moon and planets with the 130 SLT? Also, how long will the 127 Mak take to cool down to provide optimal viewing?

Appreciate any help or comments.

ps I'll be using the scope most of the time on my own, but I need to bear in mind that the kids and other inexperienced adults will want to use it and we have a small amount of time to make the most of our viewing, hence the desire for a GoTo telescope.

[ronin]

In no particular order:

Cool down, lets face it you leave them for as long, or short, as you can. If 30-60 minutes then fine if 10 then it is 10. Even if not completely cooled down you can still see pretty well through it. Bet you doin't stand the car with the engine running for 20 minutes to get it to the "normal" temperature, you just get in and drive whether the engine is cold or warm. It takes time to just stand the things up, tighten everything up, level, North, plug in, switch on and align. Thats 15-20 minutes gone and it's got cool(er).

There is no real difference in diameter so all else being equal an object will be much the same. Saturn at 120x in either should be close to identical.

Where the "difference" comes is in getting say 130x. With the Nexstar you will need a 5mm eyepiece with the SLT then an 11.5mm eyepiece. The 5mm may have to be a bit better then the 11.5 so slightly higher cost.

Newtonians need collimation at some time and I see FLO advertise a Cheshire in the suggested extra bits.

The 130 manages not to specify the mirror as parabolic, I do think that Celestron have said all their mirrors ae parabolic but I still like to see it stated in the specification. If the mirror is spherical then forget it.

The 130 will be easier to align, it simply has a wider field of view owing to the lower magnifications. May not seem like a lot but makes the scope easier to get along with.

For either I suggest a 30mm or 32mm eyepiece, it is for finding things so a good one would be nice but reasonable will do. If you got the 127 then certainly get a 30mm or 32mm you will want it to find things as the view is narrower.

For the higher magnifications then more difficult, a 5mm plossl on the Nexstar will give no usable eye relief if trying for 130x whereas a 10mm on the SLT with 150x should be OK (just). So the 130 needs better eyepieces for eye relief and like anything this costs a bit extra.

Which one? Really just preference, one needs a collimator the other needs an eyepiece to start out with. Either costs much the same. Cool down - same on both - however long you want to wait. My preference would be for the 127 Mak but not by anything tangiable - prefer the more compact design.

[shirva]

Its a cloud scope you need outside glesga ...nothing to see again. Apart from snow just now...good luck with new scope ..would suggest a modded webcam and laptop to capture the images. .as you know we don't get much viewing time up here..recording it helps in being able to go over settings ect ..and getting an other look at what you saw..you keep seeing more and more by watching video clips especially the moon..

.Davy. ..cumbernauld

[jonathan]

Playing devil's advocate here, something for you to think about...

The non-goto argument...

You say that you don't want to sacrifice aperture, going by that alone I think you could do so much better with simple tracking rather than a full goto set up. With goto you get tracking by default, but for this to work and for the goto to be accurate you still need to learn how to set up the mount correctly - you need to set the tripod down in the correct orientation (preferably, anyway), and this is where a non-goto mount set up would usually end and you can start observing (for best results allow the scope to cool as well for about 40 minutes, but that is true for either set up), for the goto you also need to spend a few minutes configuring the handset (inputting the time / date / latitude / longtitude), performing star alignment whether it be one, two, or three. I'm not sure which gives the best results, opinion is mixed. A poor star align can result in totally incorrect goto results, you won't know what you're looking for or how to find it if for example it's just outside of the eyepiece.

So, yes, the goto can find targets for you and place them conveniently in the eyepiece, but you sacrifice aperture, optical quality, and the mount for the goto mechanism and electronics. The goto is only for finding objects, once you've found them you can then invite others to view it and with accurate tracking the object should remain steady in the center.

That brings me on to another argument, the mount...

You mention that you're not sure if it's worth sacrificing optics for the mount. Well I would say yes, it is worth sacrificing optical quality in favour of the mount. You could have the best telescope in the world, but put it on a wobbly mount and you won't see anything because the view will be blurry and wobbly at the slightest breeze or touch of the mount / telescope, you'd find it a real chore to focus as every time you touch the eyepiece the view wobbles. The fact is that most supermarket or camera shop telescopes would be a lot better if they didn't come on such a pathetic mount, even Skywatcher and Celestron will usually give you the minimum mount they reasonably can for the telescope they sell it with in order to keep the cost down. A mediocre telescope on a rock-solid mount will be a telescope you'll learn to love. That is not to say all telescope bundles are bad, but the mount could usually be better (though at additional cost). Goto's usually sacrifice everything for the goto electronics, the handset can account for half of the price you pay for the whole set up; the tripod and mount will not be as good as a manual one where you have to turn a knob to perform manual tracking (usually a motor or two can be added to a manual mount to allow automatic tracking), from the thickness and construction of the tripod legs to the smoothness and strength of the gears and mount body.

If you do find yourself swayed by the improved mount / optics arguments, but are still unsure about how to find objects, a good guide can help enormously to easily find some really nice objects, both deep sky and planets. I found the Moore Winter Marathon star hopping guide to be very easy to follow, better written and with more interesting targets than the commonly suggested book Turn Left at Orion. Download the guide PDFs - there are two, one for naked eye / binoculars and another for telescopes. Not all targets will be visible in a small telescope.

Have to say though, for a manual mount set up that I would be happy to use it's going to come in closer to £500 than £350, once tracking motors and perhaps a nice eyepiece are added, plus dew shield if you go for a Mak / SCT / Reflector. My choice would be an Omni CG-4 mount with a 4 inch refractor / Mak / SCT or 6 inch reflector, something like the Celestron Omni XLT 102 with Dual Axis Motors added. This comes in at about £440, over budget but satisfies my preference for a sturdy mount (which can be used for a variety of telescopes) and which has tracking. The 102 telescope won't need collimation or a dew shield.

On the goto side I would probably go with the Celestron 4SE; it has very good optics and a decent goto system, though it is a bit of a pain that the handset doesn't have a simple time and date clock or memory for your latitude etc, so these need to be input every time the unit is switched on. I don't know what the other gotos are like, I suspect that they are mostly all made in the same factory, I hear that the Meade ones are nice but they had some quality problems in recent times. Read up on them well, download the manuals where available (usually the manufacturer's website), read through the procedures to see if you think you could understand them, ask more questions in forums about anything you don't understand.

[rowan46]

I would go for the 127slt or skymax. the eyepiece position is easier for everyone. If you are pointing the scope near zenith it can be more difficult for small children to get to the eyepiece with a reflector as it rises the higher up you look

[TheQuietEarth]

Jonathan, Ronin, Shirva and Rowan. Thanks for help and comments.

Thanks for providing me with thoughts, knowledge and argument re. non-computerised scopes, Jonathan. You've provided me with a lot if information to go away and think about. My budget is tight owing to some other upcoming expenses (new car, among other expenses) and this purchase is funded by money that's already been set aside. If I want to go over £375 I'll need to wait until May or June to purchase the scope and mount.

I understand that a stable mount is important as I use binoculars (Strathspey 10x50) and mount them to improve my viewing experience. I'm familiar with the night sky to an extent but I'd imagine that accurately pinpointing objects in the firmament with, say, a dobsonian is more involved and requires a modicum of skill and experience compared to the way I use my binoculars.

Originally I'd decided to purchase the Skywatcher 200p dobsonian from FLO after reading up about its performance and general ease of use in terms of assembly and transporting it to darker regions of my local area. But then I began to notice posts about people who'd bought it but were unable to accurately find their desired targets owing to their inability to find celestial objects. There was a person on here, for instance, who recently bought his 200p dob and was unable to find an M object despite searching for 1.5 hours! He then tried to find Andromeda and failed to do so. That's my concern with using a non-GoTo system. Sure, I have the patience and desire to learn on my own and in my own time but when I'm with others I need to be able to navigate to the target relatively easily and quickly. I'll ensure that I've got used to the GoTo alignment procedure before sharing the scope with others. I use Google Earth/Maps, Stellarium and Cartes du Ciel, so I'm familar with inputting lon/lat and other data. That should be straightforward enough with the handheld control.

In the future I'll get a dobsonian for my own use but just now the priority is a scope that will do the following...

1 - No interest in astrophotography or imaging with this scope. Observation is only priority for this particular scope.

2 - Detail on the surface of the moon is discernible and the image can be magnified to a decent level (say above x150 if atmospheric conditions support it) without losing too much detail and clarity

3 - Not as bothered about magnification of Jupiter and Saturn as long as we can make out a decent amount of detail on each (i.e. banding on Jupiter, some of its moons, Cassini division between Saturn's rings).

4 - We can observe some of the brighter Messier objects, other galaxies and that they aren't just a smudge of fuzzy light, nebulae and other DSO. How big a difference in performance in terms of observing these types of objects will there be between the 5" Maksutov-Cassegrain (say Celestron 127 SLT or 4se) and a 5" Newt like the Celestron 130 SLT? How well would the Celestron XLT or GT 102 perform compared to those telescopes in this regard?

Ronin

I take your point about the length of time it takes to get equipment ready and the time required for the Mak telescope to cool down in order to provide optimal viewing. Just out of interest, what happens if you don't wait for it to cool right down? How different will our observations be?

I think I'd prefer to go for aperture over the slightly better mount available on the 4se, so with that in mind I'd buy the 127 SLT Mak over the 4se. Also, I read somewhere that XLT coatings reduce the amount of time required to acquire images taken through the telescope and that an observer would either not notice or hardly discern any difference in image quality between an XLT coated scope and non-XLT. So the XLT coating of the 4se doesn't add anything to that scope for my needs. All I'd be paying extra for is a better mount. I'll add weight to the SLT mount and we already have a stable platform/ground that we use the binocular mount on.

Rowan

The boys will probably be tall enough to reach the EP on the 130 SLT but I'll bear what you've said in mind. I have a small step that they could use (uncles a photographer so he has equipment like this) if that was going to be an issue.

At any one time we'll probably only be viewing for an hour, maybe more. I'd prefer to ensure we get the correct scope first that suits what I've written about before giving that up for a little comfort.

With the 127 SLT Mak the image will be correctly orientated as it enters the eye, is that correct? With the 130 Newtonian will the image be inverted?

Thanks again for the help I've received so far.

[Cjg]

I would avoid the 127. It's a great scope, but with a much narrower field of view, the 130 will be more "forgiving" in finding objects in a wider field of view with the GoTo.

You'll need with either to budget for some form of power supply; 8 duracell batteries may last the "evening" in the warmth of a Californian desert, but at minus something in Norfolk in winter I think 2 hrs max if your lucky. You cannot use ni cads as the voltage is different and it will most certainly throw your goto out.

Just to throw another idea at you - Flo the forum sponsor have a stunning offer in the form of a 5" reflector and a tripod from Vixen for £280 5inches of aperture will show you lots, use an app on your phone and free software to plan what you can look at - from a dark sky you'll not struggle, start with the easier stuff and work you way along?

My first scope was a similar focal length to the 130 and now I have a Celestron 5SE, so am familiar with both.

I have goto and would not be without it from home with street lights and the tracking is useful at high power when you have a group around you....but at our observatory we have power supply and a concrete pad to ensure everything is level..

If you can visit your local astro society you may find a scope of either kind to look through too.

Good luck,

Chris

[CSM]

From what you have said a GOTO is the answer. Also consider the eyepiece height and convenience - reflectors can end up in awkward positions. Scopes up to around 130mm should give you the views you require with the Moon and planets and brighter DSO's but you would really require more aperture to get more than light smudges for the rest unless you have a really dark sky.

[rowan46]

A few people have mentioned the narrow field of view on a mak and I have to agree with them but you don't need a wide view to find objects with goto that's the computers job and it does it pretty well once you have the knack of setting them up. If your finder is set up properly finding alignment stars is a doddle and because of the goto finding a target with a mak, or sct. Narrow field of view or not is also a doddle. Yes some of the open clusters can be a bit tight but you can see most things if you have a fairly wide eyepiece in.

[TheQuietEarth]

Thanks CJG and CSM

CJG

I should have said that I've already accounted for the 12v 7-12Ah Jump Starter or Power Tank. I'd prefer not to spend over £40 for this so I don't think I'll be buying the Celestron power tank. I'll need to find one soon. I know of the £40 Aldi unit and that Maplin sell some too. Would appreciate any specific recommendations if anybody has any.

Yeah, the narrow FOV does put me off the 127 slightly and I've read on other forums of people returning them as they kept seeing dark patches of sky rather than wide fields of stars. Still, it'll be less expensive to buy the Celestron Nexstar 127 SLT as I don't need to pay for collimation tools. With the 130 SLT I need to buy the power supply and collimation tools for starters, adding another £40-60 on to the total price. At this point I will be unable to purchase any additional eyepieces until May. Still, having a working telescope takes priotrity over having a little extra left over to buy a new EP. Best scope I can buy first and I can worry about add ons in the near future.

It seems like it'll be the 130 SLT unless the 102 SLT is better suited to the needs I stated in the previous post.

102 SLT - £339 + £40 for PT. 102mm/4" aperture, f/6.5

130 SLT - £329 + £40 for PT + £5-40 for collimation tool. 130mm/5" aperture, f/5

I'm aware of the slightly less expensive Skywatcher GoTo scopes and understand that they and Celestron scopes are manufactured by the same company. I believe the Celestron scopes come with 2 year warranty while the Skywatchers come with a 12 month guarantee. Also, I've read that the alignment procedure is easier to execute on the Celestron GoTo system than the Skywatcher equivalent. Also prefer the look of the Celestron scopes.

Thanks for the suggestion re. the Vixen scope but I do need it to be a GoTo system.

CSM

The two current sites we use are only about 10 miles outside of Glasgow so darkish skies but nothing spectacular. It's a great site for binoculars though as the majority of aircraft coming from the south into Glasgow intercept the nav beacon close to the site, and you are also elevated above the city and can, if you drive on a bit, get great views over the city and towards the north.

We intend to drive down to Galloway forest park and stay overnight once we get the scope and have good weather forecasts. That'll be something special for the boys. There faces were full of awe and wonderment when they looked through the 10x50 and observed the moon's surface, so with the scope in the dark forest they'll be stuck to the eyepiece and squabble about whose turn it is!

I really can't wait myself to see how good the dark skies over Galloway forest park will be. Might go up to Perth too as we've heard there's dark skies up that way too.

I wish I had the money to buy all three scopes and share them out, then we could find out which one definitely suits us best before moving the two losing scopes on. Will have to settle for one though!

[rowan46]

If you are anywhere near hereford next week pop down to sgl8 and have a look at some scopes you will be most welcome

[TheQuietEarth]

That's a very kind offer, Brown Dwarf. Much appreciated but unfortunately I'll be stuck in Glasgow for the foreseeable future. Wish I could pop down to share the views with you and the other members who'll be attending! That would be great.

I should have bought a scope years ago but always put it off. For Christmas I thought I'd get something a bit different, so I mentioned binoculars and the Strathspey website. It was from reading about them on here and other forums that I decided they were the best people to buy from. Anyway, they arrived on Xmas day and I was amazed at how well they worked. Once night came I knew I'd have to buy a proper telescope and/or giant binoculars to supplement the 10x50s. Now I can't wait to get a proper scope and GoTo system and to share those views with friends and family. We are all looking forward to it. My friend text me last week asking if we could go for another session with the 10x50s at a dark site. Weathers been poor over past week up here though.

I can easily imagine sinking thousands into this hobby over the next decade and onwards.

[TheQuietEarth]

How accurate is the 12 dimensional string website?

http://www.12dstring.me.uk/fov.htm

If it's pretty accurate then I've just learned a great deal about the capabilities of the telescopes I've been looking to purchase. Now I'm aware that physical factors at my location when I'm observing will make a big difference to what I'll see but that website is showing me that I'll barely be able to see Saturn or Jupiter using the 9mm EP on the 130 SLT, whereas I'll get a decent view of it with the 127 SLT with the same EP.

That pretty much seals the deal for me. Seeing Jupiter and Saturn are important to me and it looks like I'll struggle to do so without buying third party or additional Celestron EPs and/or Barlows. Don't get me wrong I do intend to buy better EPs and Barlows but I want a telescope that will fulfil - at least to a decent level - the needs I mentioned earlier in this thread.

So it seems like the 127 SLT Maksutov-Cassegrain scope will meet those needs without additional expense, apart from the 12v power pack/jump starter.

Anyway, it seems like the 130 SLT is out of stock at FLO and has been for a while.

Yeah, just thinking about the kids and their reactions I think it's probably more important that we start off with a scope that, out of the box, will show them decent views of the solar system through the eyepiece than it providing weaker views of the planets and moon out of the box, like the 130 SLT will, but with the potential to get better with further investment.

If I buy the 127 SLT and then decide to purchase some new eyepieces and/or barlows a month or so afterwards will I be able to buy ones that'll improve the DSO I can see through it? I think it'll be better to do that than the other way round with the 130 SLT, i.e. seeing DSO out of the box but having to invest to see solar system objects.

Again, thanks for all the help and advice so far.

[rowan46]

If you want to see dso's better then you will need wider eye pieces ie longer focal lengths than those supplied. Because of the long focal length of the scope you don't need to buy premium eyepieces unless you really want to. I believe a 32mm is about as low a mag you can go before the baffling on the scope becomes apparrent.

[Cjg]

I have the Skywatcher 102 short tube on the goto mount - it's a great bit of kit; but not so suited to the planets, the focal length is more suited to wide field views. Jupiter in the 5SE with a 13mm eyepiece looks superb.

Celestron & Skywatcher may be made my the same company, but their menus differ on the handsets - I prefer the Skywatcher as it "beeps" when it finds the target - miss that in the Celestron! In theory the Sky Align on the Celestron will let you align by pointing at 3 bright objects in the sky, you don't need to know what they are; though I tend to get more "alignment Failed" when using it and get quicker aligns with the two star or auto two star.

Good luck,

Chris

[TheQuietEarth]

Apologies for calling you Brown Dwarf, Rowan! I looked up quickly and didn't notice that it wasn't your username.

I've never used a telescope in my life but have recently got used to using the 10x50 binoculars. I have them mounted now and use Google Sky for my mobile if I'm outside in order to locate and target objects in the sky. I stayed up late last night in order to see Saturn. Luckily my house sits in a decent location to spot objects from the front (northish) and back (south). Perhaps my mind was playing tricks on me but I'm sure I could just about make out small ears protruding from the side of the planet, i.e. its ring system. Maybe not but I spent a good 10 minutes looking at it to try and get as much detail as I could.

I feel confident that I'll be able to align the GoTo system after a few initial attempts. The Skywatcher Skymax 127 is about the same price as the Celestron 127 SLT but the latter comes with a 2 year warranty whereas the former is only protected for 12 months. The only benefit I can see for buying the Skywatcher is that they thrown in a x2 Barlow for free in addition to the 25 and 10mm eyepieces.

So is 12 Dimensional String's FOV calculator a good indication of what I'll see (assuming ideal conditions overhead) with the selected eyepieces of both solar system objects and DSO? Seems too good to be true if it is, but when I Googled the website I found a thread here where a member was saying that it's more or less accurate and a good representation of what he or she sees through their scope. I hope so as it looks like the Celestron 127 SLT will give me good views of both the planets with the 9mm omni eyepiece, with a x2 Barlow lens I'll get some stunning views of some of the M objects.

[shirva]

Hi..I'm in cumbernauld and have been into astronomy just over a year. .my first scope was a Meade etx80 a brilliant first goto scope and gave endless enjoyment. .I then found a 8" newt cheap only a copy of the sw 200 but it has good optics views from this are are brilliant..I then bought the eq3/2 pro goto mount and then the st102 and completed my scopes last week with the ed80 pro...it is expensive but rewarding if we get the weather up here..what ever scope you get ...and my advice is a quick set its too cold up here to flaf about..I have lined a hut kitted it out with led lights power points for go to ect and a couple of hours your done in by the cold.....keep it simple to start with....its a great hobby

[TheQuietEarth]

Shirva

Thanks for the advice. Some good kit you've had there and your lined hut sounds like a great place to observe from. I was just out in the garden there as it's cloudless over the south side of Glasgow just now and we got a brilliant view of Jupiter and its moons. Best view I've had since getting the binoculars over Christmas. We're mesmirsed by this symmetrical field of stars that sit just underneath and to the left of Jupiter just now. I'll need to fire up Stellarium after this post to find out what we're looking at. Never seen anything like it in the night sky. It's like a geometrical shape - like a pentagon.

What's the light pollution like over in Cumbernauld? Been over that way a few times in the last year and I imagine you'd get some good views from your location. Is there too much light in, say, Strathclyde Park to take a scope? We've got a spot up in Eaglesham, near where Rudolph Hess crashed during WW2, and it's brilliant for observing with the binoculars. Can't wait to take the scope up there. Have you been able to see most of the objects in the GoTo database from where you are?

Thanks

[ollypenrice]

You list as a priority Cassini's division in the rings of Saturn. Don't get too ambitious! This is not necessarily an easy observation...

Go To is a rum business. In a sense you are saying, 'I want to do astronomy but I don't want to do astronomy.' The thing about small GoTo scopes is that they will merrily Go To things that you can't see once Gone To. As for the things they will Go To, well, with a bit of application you could Go To them yourself with a far better telescope and get the buzz of being invoved. Many beginners find that they spend a whole session finding that they haven't got the Go To to work and they come home fed up.

If you want a good view of simple targets buy a Dob. If you want to get a good view of harder targets then learn the sky or pay a lot for a big Go To scope. Basically you don't need Go To to look at Jupiter, Saturn, the moon and a few bright Messiers.

I have large, medium and small telescopes for work but one thing is dead certain; I don't have any small telescopes with long focal lengths. Small scopes do gorgeous widefield views. Yes please!

Olly

[jonathan]

I just had a look at that 12dstring website, I think you have to take some of it with a pinch of salt as it only seems to simulate basic magnifications and field of view, not light pollution or seeing conditions which will both be major factors in deciding what you can or can't see on any given night. Light pollution doesn't tend to change that much, but one clear night is never the same as another unless you live in a desert, you may find that you can't see Saturn at all on some nights, just a fuzzy wavey blob, other nights you might even make out the Cassini division if you're lucky (and I think you would have to use some artistic imagination licence with such a small scope, too).

With my 8SE I can make out the gap either side of the planet between it and the rings, but I really struggle on most nights to see the division due to seeing conditions and local light pollution, not to mention the atmospheric turbulence caused by heat rising from roof tops (shouldn't be a factor if you're out in the woods, but poor higher altitude seeing conditions can happen anywhere, might even be worse in the forest if it's been wet recently due to moisture hanging in the air after a warm sunny day).

You should expect to see most planets as bright discs, with a hint of colour or banding. A moon filter should help with seeing some detail in Jupiter, and is definitely recommended for viewing the moon. Without one you will soon develop a purple spot in your vision which will affect your viewing considerably, it can take several minutes to pass (assuming you look away from anything bright).

Faint fuzzies are just that, and the smaller the scope the fainter and fuzzier they will be, many won't even be noticeable as they will be just too faint to see. Aperture is king for seeing those faint galaxies, nebulae, and the dimmer clusters. Most star clusters will look like a grey smudge in something like the 127 or 130, some of the brighter ones may show some stars under good skies. Open clusters are much nicer to observe in a small telescope, there are several in the Milky Way just down from Cassiopia (the W).

You should definitely be able to see the Andromeda galaxy from the middle of a forest, it is easy to find once you know where to look (just up and to the left of the Great Square of Pegasus, I believe) - it is a cigar-shaped patch of grey mist that you ought to be able to see with the naked eye if you have good skies, it is a binocular object really, a telescope will just show a slightly brighter center but it will still be just a brighter grey smudge than as seen through binoculars, and you'll probably miss out on the edges (it actually extends a long way out on either side but most of it is too dim to be seen).

I think you should go ahead and get the 127, experience it, learn its good points and bad points, and find out where you would like to go from there. You can listen to a hundred different views on the subject and end up never buying anything, when you could be out there getting all the enjoyment that you can muster from a fun little scope. If you buy a non-goto now, you will be wondering what you're missing out on, especially if you then struggle to find anything interesting other than the moon by star hopping.

To go with it you should consider a dew shield (or make one yourself, see threads in this forum for advice), a Skytron power cable (they are well made and sturdy), moon filter (ask FLO for advice on which one best goes with this scope), 12V power supply - one of those cheap emergency car starters should do to get you started, but ultimately for about £40 you could buy a medium leisure battery (which for the price will probably have far more Ah than the car starter one) and fix it up with a simple in-line fuse and battery clips; it will last you a long time compared to the cheap car starter battery which is designed for short high power bursts and immediate recharging rather than constant low power draw, which is precisely what the leisure battery is designed for. If you discharge the car starter battery beyond about half way it may cause permanent damage, so do some sums and know when to stop for recharging; you should be fine for an hour's observing, I would say, but make sure you charge it up as soon as you can (use a normal car battery charger attached to the big battery clips, red to red, black to black; any supplied mains charger is probably worthless).

PS Sorry for the essay. That's what a university education does for you I suppose... in 1,000 words!

[TheQuietEarth]

Olly

Yes, maybe I was being too optimistic about observing the Cassini division. Using the FOV calculator on the 12 Dimensional String website has given me a better idea of what is and isn't possible with the type of scope I'm looking at.

I take your point about not requiring GoTo in order to locate and focus on the three big solar system targets, and if that was all we wanted to try and see then I'd only buy the 200p dobsonian, which is what I initially wanted to purchase before thinking about the people I want to share the experience with. The people who will, from time to time, be sharing the scope with me will expect me to operate it and find targets for them to look at (children under 12, older and younger relatives and friends who have no experience with finding celestial objects or identifying them visually), but I'm a beginner myself and need time to learn how to find, say, M objects and other DSO. I'm happy to do that in my own time but when I'm with them I want to be able to do it quickly and accurately.

From reading others' experiences I'm sure that the GoTo system will align itself and find target objects. I've read more reports of beginners struggling to find DSO and the like using a manual dobsonian then I have of reading about GoTo systems that either don't align properly or can't find targets, and when I have read stories like that the person's handheld computer has crashed, needs a firmware update, or the person has utilised an alternative alignment method to get the system working.

As I said above there was a poster on here who initially wanted a GoTo system but then decided to buy a 200p dob. He subsequently failed to find targets despite searching for a total of 2 hours or more. Consequently he was limited to looking at Jupiter, the Moon and Saturn. I don't want to haul a telescope up to a cold Glaswegian forest only to spend hours trying my hardest to find anything other than those three solar system objects.

Still, I haven't completely ruled out the 200p dobsonian. If it isn't going to be suitable this time round then I'm certainly thinking about purchasing it for myself later on in the year.

[TheQuietEarth]

I just had a look at that 12dstring website...

Jonathan, thank you very much for taking the time required to share all that advice with me. That's been a great help, especially the information in the last paragraph.

I still haven't made any firm decision about which scope to buy and I'm going to wait a week or so to make up my mind. I want to read up a little more, make some basic calculations based on the price of the scope and accessories as each model differs in terms of the final sum required, and talk to family members to see how they'd feel about using a manual scope.

From the 12 D String website it simulates some good planetary views with the 127 and an EP like the Celestron X-CEL LX 9mm. Similarly, with the 25mm plossl and the same telescope it simulates good views of M42. Now if that's an accurate representation of what we'll see - and I've taken on board that it's never going to be an entirely accurate model for many reasons - then it seems like a wonderful scope for our needs. I found another conversation on here where a poster with a high post count stated that it's untrue to say that the narrow FOV will prohibit observations on Messier objects using the 127 SLT. Indeed, he goes on to state that an observer will see most of them with that scope given the right conditions.

Re. the power supply - I've more or less resigned myself to paying the extra £20 or less for the Celestron power tank. (Will the Skywatcher also work on the Celestron scopes?). I don't want to mess about with leisure batteries or buy a cheap jump starter that won't work after a year. If I buy the 127 Mak then I'll definitely be buying the proper Dew shield too. Was going to leave the filter until later on in the year but if it causes problems like the one you've described then I'd rather avoid that, especially if others are using the scope.

Going to read your post again to see if there's anything I've missed. Thanks again for sharing your knowledge and advice with me.

[shirva]

Hi.again. my view from cumbernauld is towards palacerigg area..like any populated area light pollution is a pain..weather quite bad here a lot of time but can get nice views...shed helps its run on@12v dc on a car battery solar charger and have power points for astronomy. .a shed a must I would say for spending time observing pulling kit in and out house soon annoys the misses and takes up time...advise against maplins cheap starter pack got one , don't last jig time, get a leasure battery , I work with a auto electrical mob in springburn so get latest kit n gadjets to help in astronomy. Have a look at m45 just above and right of jupiter cracking sight for first timer.

[shirva]

The goto helps but as stated depending on scope used and magnification. ..some items on the tour section I haven't had wiff of wondered if even had scope lined up right..the goto as I said is a help and a quick fix for me if I like the picture of a object I use the goto, if I did not work yip great would spend more time learning the skies but its a hobby and dosent put bread on table or roof over the head.and want to spend time on the learning astrophotography side of things the stars have been there billions of years so might be there long enough to learn where they all are....lol...

[TheQuietEarth]

Thanks again, shirva.

Hopefully going to the darker sites miles outside of Glasgow will help us pick up some objects that aren't available under the LP skies of Giffnock. We're definitely planning to load the van up with the scope, binoculars, tents, food and excited children and then head down to Galloway Forest Park, which I believe has some of the darkest skies in the entire UK. I've been lucky enough to visit the summit of Mauna Kea (lots of observatories, including the twin Keck units) and see how much better the heavens are when LP is low. Was totally exhausted due to the thin air at that altitude. Felt like I'd been running in a marathon! Funny things is that it wasn't the stars that mesmerised me that evening - it was the burning pools of lava that we could see from the summit that made my stomach knot up. Never seen as spectacular a light show as that before or since. Stunning.

Anyway, about this new hobby. I forgot that the 127 SLT is slightly more expensive than the other two SLT scopes (£359 from FLO) and I also have to buy a power source and dew shield. This goes beyond my budget. I've now added an extra £15 to the £375 I've set aside but I don't want to spend over £400 this month.

Are there any 12v xAh Gel batteries and charger for under £40? From reading other posts on here it seems like Gel batteries are better than the lead flooded equivalents. I'm weary about buying the Celestron Power tank as it has the potential to discharge too far and cease working. As I understand it after reading a few posts on various forums Gel batteries can be discharged to a much deeper level and are better suited to powering a GoTo system. I think I'd prefer the Gel battery or AGM type over the lead ones you find in budget jump starters. I intend to weigh down the mount with either the battery and/or 1 Kg iron weight. My friend is in construction and is prepared to supply some small sand bags for the legs if necessary.

It's finding a solution to the GoTo power issue that's causing me the most concern. There are cheap alternative solutions for the dew shield so I'm not worried about that. It's more important to buy the scope and a power source than the scope and dew shield as I can't use the thing without power!