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Telescope advice. (Read 11983 times)

Mike Tyson

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Telescope advice.
November 05, 2012, 10:17:45 am
Bit of a random one this really, but UKB seems to have the power to answer most questions so I may as well ask here.

My kids are both interested in the stars and planets, and I was thinking of buying them a telescope for their room. Any keen astronomers on here who could point me in the direction of a good telescope for around the 100 notes region? I appreciate you probably can't get a world class one for this price, but was hoping for something of decent quality.

Thanks in advance.

mark s

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#1 Re: Telescope advice.
November 05, 2012, 10:25:53 am
message turner.he goes on the second hand astro sites.he knows what to get for moon gazing and planets

SA Chris

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#2 Re: Telescope advice.
November 05, 2012, 10:52:18 am
A friend of mine got one of Infinity telescopes for his kids and they love it and he was raving about the quaility, although I never saw it in use, or have anything to compare it to.

This type of thing, might be less if you shop around.

http://www.microglobe.co.uk/skywatcher-infinity-76p-children-parabolic-reflector-telescope-p-8376.html

get one for each of you; no squabbling!

Although I'm sure one of the pundits will be along to slate it shortly.

underground

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#3 Re: Telescope advice.
November 05, 2012, 10:53:02 am
I'm no expert on this but did the same research as you last year. In the end there was a shortage of lenses and no stock of my scope choice, by the time there was the whole year had been rainy and I decided not to bother.

The general consensus seems that at the lower price end, a Dobsonian is the one to choose for light gathering ability and ease of setup/star tracking. I think the simplicity is best for kids too.

like this one

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#4 Re: Telescope advice.
November 05, 2012, 11:15:03 am

chris j

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#5 Re: Telescope advice.
November 05, 2012, 12:17:12 pm
A friend of mine got one of Infinity telescopes for his kids and they love it and he was raving about the quaility, although I never saw it in use, or have anything to compare it to.

This type of thing, might be less if you shop around.

http://www.microglobe.co.uk/skywatcher-infinity-76p-children-parabolic-reflector-telescope-p-8376.html


The missus' uncle has been recommending it to us for Xmas presents for all the grown up kids in the family. I wonder if there's any way of attaching a camera to it for taking photos of the moon surface etc (though I suspect you need to spend a vast amount of money for that sort of thing...)

Stu Littlefair

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#6 Telescope advice.
November 05, 2012, 12:17:39 pm
Some good knowledge here. The telescope Chris suggests is great for kids as its robust and good quality.

If your kids are a bit more careful with their toys then a slightly larger skywatcher scope is probably the best bet, although its slightly out of your budget it's an excellent scope for the price

http://www.amazon.co.uk/gp/product/B005KIXM66/ref=as_li_tf_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=B005KIXM66&linkCode=as2&tag=meteorwatchor-21

The optical quality is really nice and the views are excellent even with the included eyepieces. The Moon, Jupiter, Saturn, Andromeda Galaxy, Orion Nebula etc are easily visible with this telesscope.

There is a red dot finder included which will massively help actually finding stuff.


Johnny Brown

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#7 Re: Telescope advice.
November 05, 2012, 12:27:43 pm
Pretty tempted myself for that price. Is it a big jump in price to get better quality or are you mainly paying for a motorized mount etc? I daresay I'd be tempted to start attaching a camera...

mark s

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#8 Re: Telescope advice.
November 05, 2012, 12:30:07 pm
A friend of mine got one of Infinity telescopes for his kids and they love it and he was raving about the quaility, although I never saw it in use, or have anything to compare it to.

This type of thing, might be less if you shop around.

http://www.microglobe.co.uk/skywatcher-infinity-76p-children-parabolic-reflector-telescope-p-8376.html


as far as i know its a small plastic adapter than your web cam fits on to.wont be more than a few quid

The missus' uncle has been recommending it to us for Xmas presents for all the grown up kids in the family. I wonder if there's any way of attaching a camera to it for taking photos of the moon surface etc (though I suspect you need to spend a vast amount of money for that sort of thing...)

mark s

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#9 Re: Telescope advice.
November 05, 2012, 12:31:48 pm
oh,that came out a bit muddled up



the bit i put was its just a plastic adapter to put the webcam on to.

Johnny Brown

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#10 Re: Telescope advice.
November 05, 2012, 12:37:58 pm
I was thinking more of the one Stu linked. The bowl base looks a bit limiting on the kids one.

Mike Tyson

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#11 Re: Telescope advice.
November 05, 2012, 02:07:20 pm
Thanks for the advice all, the links all look good TBH but I am tempted by the one Chris mentioned as it is funky looking and I could get them one each! Will be looking at them all in a bit more detail later, off to fix a wall now in the glorious Lake District sunshine!  :2thumbsup:

SA Chris

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#12 Re: Telescope advice.
November 05, 2012, 02:44:58 pm
just get the google skymaps app!

Stu Littlefair

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#13 Re: Telescope advice.
November 05, 2012, 03:05:03 pm
Pretty tempted myself for that price. Is it a big jump in price to get better quality or are you mainly paying for a motorized mount etc? I daresay I'd be tempted to start attaching a camera...

If you go for one with a motorised mount etc you're going to pay a lot more, and for less than 400 smackers the view will likely be pretty poor in comparison.

This video gives a decent idea of the kind of views you can expect.


SA Chris

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#14 Re: Telescope advice.
November 05, 2012, 03:37:51 pm
I wonder if there's any way of attaching a camera to it for taking photos of the moon surface etc (though I suspect you need to spend a vast amount of money for that sort of thing...)

Again this is unsubstantiated, but he said he got some good pics just holding his point and shoot to the viewfinder. Although I doubt they are Andi Turner quality.

Drew

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#15 Re: Telescope advice.
November 05, 2012, 06:56:59 pm
The site seems to not be working at the moment, but I'd be interested if Andi T etc agree with this

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#16 Re: Telescope advice.
November 05, 2012, 09:11:56 pm
Drew, I'd say there's some pretty sound advice on there. Skywatcher telescopes on a whole are as good as any chinese kit you can buy is. The kit is well thought out and the mounts are normally well matched to the telescopes. The infinity scope is a good buy too, you can take it away camoping, plonk it on your bonnet or a picnic bench and you're good to go. There's all sorts to consider when buying a telescope, it's a bit like when someone asks what climbing boots to buy for the first time....if they go too cheap then they'll never really get the benefit and soon take up scrambling instead, too precise and they'll end up in pain.

You'll need a good mount whatever you get. A wobbly scope is no fun. Anything above about 8 times magnification needs a good mount (binoculars included). A lot of mounts these days are 'goto'. This means you align the mount at the start of the night and then you can simply punch in 'Saturn' or 'Orion Nebula' and it'll swing the scope to it for you. Saves a lot of hassle.

Adam, if you're gonna get into, save your money and go straight into the astrophotography side of things. You've got a good camera and lenses already. Stick them on an Astrotrac and you'll soon be getting some very nice results. The thing a lot of people don't realise is the size of the objects that the astrophotographers image. My main imaging scope is a Takahashi FSQ-85, which is basically a 450mm lens, I normally further reduce that to 330mm F3.9, even at this focal length a lot of objects are too big for my camera sensor. A high quality 200mm lens (the Leica Telyt Apo 180 is a pretty legendary astro lens) which get you well on your way. A nifty 50 will capture the whole of Orion, and there's a lot going on around there.

So, £100 won't get you very far, but in the same ball-park you should be able to get a Skywatcher 130 on some sort of reasonable mount and that would be money well spent. Worst comes to worst, they sell for about 3/4 their new price anyway on ebay.

If I had around that money to spend on a first scope however, I'd buy this http://astrobuysell.com/uk/propview.php?view=62332

SA Chris

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#17 Re: Telescope advice.
December 13, 2017, 06:06:08 pm
Resurrection....

Son has expressed an interest in a telescope for Xmas, and TBH something I've always fancied too, so something maybe a bit better than the infinity I mentioned before, which I've used and is pretty decent,

Celestron Powerseekers seem to get a lot of recommendation, but a minefield of varieties! Ideally something both of us can use, be nice to be able to mount up a DSLR if possible. Budget - £150ish, a bit over if it can be justified. Or any alternatives. TIA

Stu Littlefair

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#18 Re: Telescope advice.
December 14, 2017, 11:32:56 am
To be honest, most of the advice on this thread is still valid: things move pretty slow in the telescope world.

Given your budget, think seriously about your desire to hook a DSLR up to it for anything other than shots of the Moon and Jupiter/Saturn. The issue is not so much the scope, as getting a mount that will track well enough to allow photography for anything less than £500ish. Even within budget, you'll have to give up a lot of aperture* and optical quality to get a motor drive that will allow (disappointing) photography. Whatever you decide, save a few pounds to buy "Turn Left at Orion" - a lovely book which will be a source of things to look at for years to come.

If you purely want a telescope to look through I would strongly recommend a Dobsonion based telescope - no motor drive, easy to point by hand plenty of apeture for your buck. I love this chap, but he's over your budget:

https://www.firstlightoptics.com/beginner-telescopes/skywatcher-skyliner-200p-dobsonian.html

The smaller Skywatcher Dobsonions (130p and 150p) are nearer your budget and also grand.

If you stick to the original idea, and budget, the best bet in that case is still this bad boy:

https://www.firstlightoptics.com/beginner-telescopes/skywatcher-explorer-130m.html

The tracking of the motor will be very disappointing if you want to take pics of Galaxies etc.

*aperture is about the most important aspect of a telescope - all else being equal a bigger aperture will allow you to see fainter objects and more detail. Since you've got some nice dark skies in your neck of the woods, you'd really benefit from this.

SA Chris

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#19 Re: Telescope advice.
December 14, 2017, 12:05:24 pm
Thanks Stuart, shots of Moon / Jupiter / Saturn / some constellation is all I would hope to get.

One of reasons I'm interested is I've got an internal astrotracer on my Camera, which i've not really used in anger and like to see what it can do.

https://www.outdoorphotographer.com/photography-gear/cameras/pentax-k1-astrophotography-camera/

I think the "5 min" quoted would be reduced drastically with a telescope though.


Stu Littlefair

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#20 Re: Telescope advice.
December 14, 2017, 04:05:28 pm
If you assume that 5mins is for a wide angle (15mm) lens, then the time you'll be able to expose will drop in proportion to your focal length. The 130m has a 900mm focal length, so you're looking at 5 seconds!

The tracking of the mount provided probably will allow more than that (maybe 10-20s) but I don't think you can combine the two, which is a shame because that would be amazing!

Andy's advice for astrophotography below is top-dollar, unsurprisingly. Many of the astrophotography pictures you've seen will be taken with telescopes of 400-600mm focal lengths and you can get really good pictures with a fast telephoto, which you may already have.

It's a tough call, but for people on a budget my advice is usually that you can buy:

1) A telescope on a motorised mount that will be disappointing for astrophotography and ok for visual use
2) A telescope for visual use only, but it will be heads and shoulders better for visual use.

SA Chris

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#21 Re: Telescope advice.
December 14, 2017, 04:23:11 pm
Astrotracer is also unfortunately limited to stars only (based on GPS and internal compass), no override, so no good for moon or planets.

Thanks otherwise Stu. I'll have a closer look and decide between the 2.

Johnny Brown

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#22 Re: Telescope advice.
December 13, 2018, 10:21:19 pm
So after my annual perusal of this thread, this year I actually did some further research. What stopped me in the past was that I was convinced (from my photography and binoculars) that anything under £400 was going to be irredeemably shit. Summary might be useful for anyone interested.

So initially I set a budget of about that. I ruled out refractors very quickly, I've used cheap ones before (see conclusion above) and I've already got a cupboard full of exotic glass telephotos. Reflectors seemed more interesting, physical aperture being far bigger, and value that became more astonishing the more I read. Basically the construction is very simple, there is only one optical surface and it's left up to the user to align (aka collimate). Second hand, you can get a thing that looks like Hubble for under a monkey! Tempting, but what I really needed was something portable and quick to set up, so I ended up back at the Heritage-130p Stu linked above, the only small collapsible dobsonian afaik. But it still seemed too cheap to trust. After reading most of the internet, I was finally convinced it was worth a punt, and I won a barely used one for £85 on eBay, cash on collection in Glossop (price new £135).

Driving back from picking it up, the clouds cleared as I passed Stanage and the moon appeared, so I pulled in and set it up. After some difficulty aiming it I found the moon. Fucking hell! Looks amazing. Switch eyepieces, from 25 to 10mm. Fuck me! This is the best £85 I ever spent. Had a further look around, found Mars, and what I'm fairly sure was Neptune. Wow. Quickly got the hang of pointing it, easier than a spotting scope despite the rotated view. Now also have the red dot finder set up which is brilliant.

Anyway, bargain, highly recommended. Nice height for kids too, and pretty simple and robust.

And I have £320 left to spend on exotic eyepieces, any suggestions?

Stu Littlefair

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#23 Re: Telescope advice.
December 14, 2018, 09:12:40 am
Glad you like it!

I can point you to some excellent notes about eyepiece optics 😉

http://slittlefair.staff.shef.ac.uk/teaching/phy217/lectures/telescopes/L08/index.html

For that scope you’re looking at eyepieces in the range 5-40mm being useful. I don’t know what eyepieces you currently have but from your text above you might want to splash out on something wide field; ie nearer the 40mm range which will give you a magnification of 16x. You can divide the apparent FOV by your magnification to give you an idea of true FoV.

We use the celestron luminos eyepieces with the students. Really nice.

https://www.firstlightoptics.com/celestron-eyepieces/celestron-luminos-eyepieces.html




Johnny Brown

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#24 Re: Telescope advice.
December 14, 2018, 11:27:03 am
That's great, thanks. It's only 650mm, so from what I read anything longer than 32mm is likely to show the secondary?

It came with a 10mm and a 25mm. They are better than I expected, but the afov on the 10mm is very small. Assuming a better short ep with a wider angle would give a wider true field of view, i.e allow less frantic repositioning?

Paralysed by choice on eyepieces tbh. I'd been looking at the Skywatcher panorama which are supposedly repackaged Luminos, but forums suggest they might not be great at f/5? Forums suggest ideal for this scope is ES 68 24mm, plus Meade 5000 5.5mm or ES 82 6.7mm. Pricey! Currently leaning towards ES 62 26mm, OVL Nirvana 7mm (£75) plus a barlow. But I dunno... might just get the 7mm for starters.

Nice view of Venus this morning, even through the double glazing Jake could describe it a a 'white banana'.

Stu Littlefair

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#25 Re: Telescope advice.
December 14, 2018, 12:30:42 pm
That's great, thanks. It's only 650mm, so from what I read anything longer than 32mm is likely to show the secondary?

Perhaps; what matters here is the size of the secondary mirror in the "exit pupil plane" compared to the size of the eye's pupil. The secondary is about 30% of the diameter of the telescope, so will also be 30% of the exit pupil.

A 40mm eyepiece will give an "exit pupil" of 8mm, which is a good match to the pupil size of a healthy dark adapted eye. At 30% of this, the secondary shadow will be 2.4mm, and you shouldn't notice the secondary. However, if you look through it in daylight, when your pupil is much smaller, it will be obvious. It will also be apparent if your pupil doesn't dilate much, or when you first go outside.

32mm is a nice choice though; it will give you 20x magnification, which with a 80 degree AFOV would give you a 4 degree field; a nice match for objects like the Pleiades and Andromeda (which are ~2 degrees across). Maybe stick with that and be safe. A 26mm will be OK, but the view of larger DSOs might be a bit tight?

Don't get too paralysed by choosing an eyepiece; most modern eyepieces are excellent, and you know what forums are like for spending time getting hung up on pointless minutia! I'd start with 2, something around 32mm, something around 5-7mm and see if you feel there's a gap missing after that.

Do you have the book "Turn Left At Orion"? It has lots of ideas for things to point your scope at. Don't miss out double stars. Albireo is one of my favourite things to look at; https://earthsky.org/brightest-stars/albireo-finest-double-star


Johnny Brown

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#26 Re: Telescope advice.
December 14, 2018, 01:02:26 pm
Ok thanks, that's useful.

I got a decent view of the Pleiades last night with the 25mm but they did fill the view. Doesn't seem to be much choice of longer eyepieces in 1.25" though? Suppose I'll pop over to Rother valley and have a look at a few.

Was also looking at Cygnus last night, shame I didn't know which star to go closer on!

Yes, that book is on the xmas list...

Johnny Brown

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#27 Re: Telescope advice.
January 31, 2019, 02:54:48 pm
Update: so six weeks or so on I've been getting a lot of use out of the scope. Have made a couple of trips out to darker spots at Stanage and Ringinglow but these seem more prone to cloud, so mainly in the back yard.

Did a lot of research on eyepieces. The ES 26mm 26degree (£97) I went for is great for widefield. It gives I think the max TFOV possible (2.5 degrees at 25X) and a really great view - Pleiades look fantastic. Feels like a premium piece.

Also got a 6mm Baader classic ortho (£50new / £30 used). If I was buying again this is the first upgrade I'd suggest, gives 108X. I haven't had a problem with the tight eye relief and the limited glass makes for sharp, contrasty views. Tiny and light. Effectively parfocal with the 26mm, which makes a nice combo.

Did a bunch of mods, in order:
Made collimating cap from 35mm film case.
Flocked light shield.
Greased focuser threads with chapstick.
Made full light shield (telescoping tube) with eva foam and sticky-backed plastic.
Cleaned primary in sink (carefully!)
Drilled and tapped a second hole on dovetail rail to take an arca rail to mount on tripod. A big ballhead slacked right off works surprisingly well as a alt/az mount.

Also bought a couple of other eyepieces - Baader 8-24mm zoom. It's great quality but pushing it weight-wise on this scope, it also requires a lot of in-focus which makes it a bit of a hassle swapping with other EPs. I'll hold onto it as it's great on the moon and wide pairs, and I suspect will be better on a longer fl scope.

4mm Nirvana 82 degree (£75). These Nirvanas are touted as the best bang-for-buck EP out there. I like it - 82 degree gives the 'spacecraft window' effect where you swivel your eye and can barely see the edge, but at 4mm it needs good seeing and is a bit dim and lower contrast compared to the ortho.

Stu, any beta on the best star atlas? Found a decent free PDF and prompted by your Albireo suggestion have been ticking my way through the best 200 doubles list. Cosmic train spotting as Varian put it is about right, well it's better than tv. Waiting for the new edition of Turn Left, looking forward to planets being better positioned. Not bothered looking for DSOs as the view of Andromeda from the backyard is underwhelming to say the least.

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#28 Re: Telescope advice.
October 23, 2020, 04:17:53 pm
Me and the kids have been making do with a 1970s USSR 33T20x50 telescope taped onto a camera tripod. Having fun, but would like something "better"

based on the info in this thread (thanks!) I'm looking for second hand Skywatcher Dobsonians on Ebay, but not managed to score yet

any recent developments in the used telescope scene that I should consider?

cheers

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#29 Re: Telescope advice.
October 23, 2020, 04:55:48 pm
My telescope advice is to always check the eyepiece to make sure no one has smeared black goo or paint around it 👍

Johnny Brown

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#30 Re: Telescope advice.
October 23, 2020, 05:33:14 pm
I'd say definitely go for a skywatcher dob. As big as is practical, the 5" is a good intro for cheaps but go bigger if you can. My small one is not getting much use if you want to try?

Since my last post on here I bought a 10" tube and then rebuilt it as a plywood and truss combo which is my main scope and much more portable. You can pick up 8" dobs in good nick for £200, or 10" for £350 ( both my scopes were ~£75 used but I spent a £300 on the rebuild. The sky really opens up with the bigger scopes, both the resolution and fainter objects. I've also got a spotting scope and a box full of eyepieces now... the included ones will get you going but budget for some upgrades.


lagerstarfish

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#31 Re: Telescope advice.
October 23, 2020, 06:45:05 pm
nice one JB

I'll put some G4S stickers on the van and do a fake Covid Enforcement Raid on your street - we can load up the dob while your neighbours run away screaming or hide in their cellars - you can tell them that I found your mother in-law doing some illegal child minding and that she is now locked up for the duration.

Johnny Brown

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#32 Re: Telescope advice.
October 23, 2020, 07:38:32 pm
Books...

Turn Left is great but quirky. Firstly it's massive so a bit unwieldy, but spiral bound which helps. It's all black and white, very basic artwork, and the decision to use star names and no RA/ Dec makes it a bit patronising and unrealistic, like you'll never use any other resource. But for actually finding stuff it's by far the best.

Collins Stargazing should be free with every beginner scope. Big pocket size, perfect balance of info, nice photos, great choice of targets and brilliant maps. Only fault is the maps have a few gaps when it seems with a few more they could have squeezed in a full atlas. £8 well spent.

Companion volume Collins Moongazing is dogshit. Seriously, poor maps, poor info and half the book filled with poor info on photography. I want my seven pounds back.

Collins 2020/ 2021 etc annual guides. These are great, most of the info you get in a year's magazine subscription in a slim pocketable volume. Occasionally miss big events, and not sure if the star informs the same year to year.

Collins Stars and Planets. 5th edition, £15. If you get into it you won't grow out of this one, comprehensive, essential. Might be a bit dry for kids. Some of the older used editions have even nicer maps.

Astronomy a visual guide. DK, £15, comes in a fancy moon embossed slip case. Probably the best single book for an interested teen but imho tries to do a bit much while remaining accessible.

Sky & Telescope's Pocket Sky Atlas is the proper atlas to get first. Decent size, excellent water resistant card pages and plenty of detail, likely to have most of your targets. For me much better than an app, but in combination with the internet you probably won't need another. The Cambridge one is much bigger and has flimsy paper, but their Double star atlas is essential if you get into them.

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#33 Re: Telescope advice.
October 24, 2020, 09:38:59 am
PS not much goes on eBay, everybody uses astrobuysell.com/uk

And check the buy/sell forum at stargazerslounge.com.

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#34 Re: Telescope advice.
October 24, 2020, 11:22:11 pm
PS not much goes on eBay, everybody uses astrobuysell.com/uk

And check the buy/sell forum at stargazerslounge.com.

Nice one

Cheers

Johnny Brown

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#35 Re: Telescope advice.
October 25, 2020, 06:03:14 pm
This is a great little film that might push some of you over the edge:


Duma

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#36 Re: Telescope advice.
October 25, 2020, 08:30:40 pm
That's lovely

Johnny Brown

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#37 Re: Telescope advice.
November 02, 2020, 03:41:59 pm
Eyepiece upgrades

I would suggest you set aside at least half your budget for eyepieces. They define the quality of the view more than the scope and the included ones are typically pretty poor. The good news is you only need two or three to start and can pick up more as you go along, plus they'll work on any scope and hold their value well. If you're not in a rush wait for them to come up used - most are in perfect nick as they don't leave the house. However the variety is baffling, a bit like popping into a West Indian record shop because you liked Legend. In my experience you can only really judge them on the stars so I wouldn't bother with a shop visit either (Rother Valley optics are hopeless, unless you're near somewhere better). So assuming you're buying on spec...

Focal length
You want something to give you the widest view possible, for big objects and finding stuff. This means a long focal length >24mm. For bigger scopes this will mean a big, heavy, pricey 2" piece, for a 1.25" focuser you have less choice - more below.
Then you want a high power eyepiece about the same length in mm as your scope's focal ratio - i.e. 5mm for an f/5 scope, 10mm for an f/10.
Double the high power and you've got your mid-power, i.e. 10mm for f/5, 20mm for f/10. This is actually likely to be the one you use most so the advice is usually to spend most here.

Apparent field-of-view (AFOV)
Expressed in degrees, typically from 50-100o, determines how big the view appears to the eye. 60o and up is considered wide angle, above 80 'hyper' or 'ultra' wide. You can take in about 60 without moving your eye, above 80 the edge of the view ('field stop') is increasingly in your peripheral vision, so you have to peer around to see the edges. This is often touted as a more immersive view, and it has the practical benefit that with an undriven scope you get more looking time before having to nudge it along. If you've not used an ultra wide the first time is quite a treat.

The other stuff - sharpness, contrast etc are what you pay for but harder to derive from specs. Both will improve with magnification up to a point then decline again - this is one reason your mid-range Ep will excel. Have a read of Stu's post on exit pupils above - things will generally peak around a 2mm exit pupil, i.e a 10mm eyepiece in f/5 scope.

A lot of the lower-mid price range are the same optics in different bodies. Read some reviews. I'm not convinced by zooms (I have the Baader ) - unlike photography there isn't much call for tweaking the view, more jumping to a significantly different mag, plus they have have variable AFOV which declines so you just get a bloated mid-range piece which shows a similar view bigger or smaller.

Some brands for starters.

Svbony - Russian EPs via ebay. A modest upgrade on your included ones for a few fuck-alls.

BST Star guider - usually the cheapest recommended, ~£50 a pop new.

Explore Scientific - a big range with prices and quality that go up with the AFOV. All seem very well regarded. I've got the 26/62o, 24/68oand 8.8/82o.  £100-150 new, used ~70%. The 8.8mm is a gem, cost me £85 and probably my favourite but this is partly due to a ~2mm exit pupil in my scope.

Meade - a bit of a mixed bag but the 5.5mm and 8.8mm UWA 82o are very good. I've got the 5.5mm £130.

Skywatcher Nirvana - cheapest well regarded ultrawides. £75. I've got the 4mm, its decent.

Televue, Pentax etc. The best but you won't be buying them based on my opinion. >£250. I've got one Nagler, it's almost perfect but not twice as good as the Meade 5.5 or ES 8.8mm.

The other issue is getting the widest view out of a 1.25" focuser. The alternatives are limited, same true field but as the afov increase the price and performance goes up:
32mm plossl £30 might not be an upgrade on the included
ES 30mm 52o £70
BST 25mm 60o £50
ES 26mm 62o £100
ES 24mm 68o £140 (£85 used)

There is a similar choice around 2" max view but I'll not bother unless anyone asks...

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#38 Re: Telescope advice.
November 02, 2020, 03:51:45 pm
PS... In that moon vid your man has got a £600 Televue 100o Ethos eyepiece operating at about 115x and a 2.5mm exit pupil. That's delivering a view of the whole moon in blistering detail but with the edge right out into your peripheral vision, like someone holding a 2m diameter model a meter away. That's why they're gasping.

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#39 Re: Telescope advice.
November 02, 2020, 06:26:35 pm
One thing I forgot - Baader orthos. Low price, limited field of view, very sharp, high contrast. £35 used, £50 new. If you don't want to spend much a 6mm would be a good choice for your first addtional EP for an f/5 dob.

Similar 'minimal glass' EPs are popular with the beard stroking crowd for keeping out maximum detail on planets (which are all tiny even in any scope btw, except the moon), although they tend to go for pricey Japanese ones that aren't made any more. Downside is very short eye relief which takes a little getting used to and is a complete non starter with glasses.

 

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