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MikeASiegler

Hi, I'm relatively new

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And I'm looking for any tips someone can give me on spotting cool things. I have an astromaster LT 76 AZ by celestron. D=76mm and F=700mm with a 10mm and a 20mm eyepiece. Any tips are appreciated. [emoji2] [emoji573] [emoji287]

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Welcome to SGL.

The max magnification on your 'scope will ne about 140X. Your 10mm will give 70x and the 20mm 35x.

So a single 2x barlow will double those.

This will allow views of Saturns rings and major moons, Jupiter and its major moons. Of course the Moon will be in good detail and when winter arrives the Orion Nebula will be very nice indeed.

Get a copy of Turn Left at Orion. It has pleanty of objects to choose from and grades them into suitability for small, medium and larger 'scopes.

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First a "stronger" lens will make things bigger and that make them dimmer and usually more difficult to see. And as Deeper things are dim then making them dimmer is not the best idea. The problem with astronomy is that you have a very limited amount of light and this works against you.

I will presume that the supplied items are Kellners and Huygens and although possibly reasonable the  supplied ones tend to be inexpensive so poorish.

Would suggest you look at a few reasonable plossl's, GSO and Revelation ones are fair.

I would expect that scope to deliver not much more then 100x before the image quality drops off, that implies an eyepiece of 7mm.

I would usually say consider 4 eyepieces and using the f number of the scope I would initially think of 8mm, 10mm, 15mm, 30mm.

What to look at depends on what you want to look at.

Double stars: Alberio, Mizar, Double-double, Gamma Andromeda.

Planetary nebula: Ring Nebula, Dumbbell Nebula.

Clusters: M13, double cluster + Several others.

Galaxies will be more difficult, Andromeda is too big to fit in your field of view - use binoculars, Triangulum may be too faint, Bodes galaxy maybe.

For Saturn 100x will be needed and preferably 120x.

Alternatives to plossl eyepieces are the planetary eyepieces that are avail;able, Sky's the limit, TS and FLO have some. I use BST Starguiders in preferenc to planetary's - simply they work better but cost more. Planetary's tend to have more selection at the shorter focal lengths and a constantish eye relief. The selection means you can get them in 1mm differences so

Edited by ronin

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Ronin would you happen to have a link where I could look into getting a better lense? I don't know where to start. I'd like to get several eye pieces to see whatever I can. I also intend on getting a better telescope at some point because I really would like to see much of what the universe offers.

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If anyone could answer this that would help. Like I said I have 700mm telescope and a 10mm eyepiece. Too see farther I would need a stronger telescope (say 1000mm) and a smaller mm lense? Sounds like a dumb question lol but I'm extremely new

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Hi Mike, welcome to SGL.  It's the aperture of the scope that matters when considering deep sky (DSO's as we call them) not the focal length of the scope, the more aperture (wider objective, lens or mirror) the deeper you can look into the universe.  To make any real difference you are looking at a reflector with at least 150mm (6") or 200mm (8") so quite a bit more than the 70mm you already have.  FLO, the lounge sponsors are the best shop on the planet, so have a look there by clicking on their banner.  You will not see further by increasing the magnification on your present set-up, an 8mm eyepiece giving you 87x will probably be the best you can do, although the 7mm giving you 100x as suggested above may be acheivable and perfect on planets.

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Hi there, I started with a similar telescope (different brand).:-)

I don't know how sturdy the celestron mount is, this was always the limiting factor for my set, and especially when using higher magnification.

Sadly, this is for many starter sets and many beginners give up frustrated - not because the optics are bad, but due to cheap accessoires and the lack of literature on how to localte galaxies and such.

Higher magnification is not everything, with 700 mm focal length a 10mm eyepiece will give you 70x (700/10=70) and the other eyepiece 35x.

I also reccomend getting "turn left at orion" as it helps you find things, explains a lot, and shows you what to expect.

The andromeda galaxy, m81/m82, the ring- and dumbbell nebula (later the magnificent orion nebula), star clusters hχ persei, m13, the coat hanger and many more become visible even with lower magnification.

The best result for deep sky will be with an eyepiece with around 2-3mm exit pupil (exit pupil = eyepiecemm devidedby focalratio)

(focal ratio equals telescopeFocalLength devidedby Aperture)

So while the 20mm eyepiece gives you little magnification, it will still show you a relatively bright image with a dark sky background, giving you more contrast for deep sky observations.

Smaller objects such as the ring nebula or star clusters may benefit from a bit more, say, 70-100x.

A few Objects such as the orion nebula, open star clusters (plejades!) actually benefit from low magnification.

Don't spend a lot of money on accessories now.

Was there a barlow lens included?

(a tube that comes inbetween telescope and eyepiece, increasing magnification by typicaly 2x).

I would also suggest not going much over 100x. But despite better eypiece quality, 8mm may be a bit too close to what you've got.

Seben germany sells cheap plössl, and while their telescopes get a lot bad reviews, I find their plössl and erfle eyepiece a great deal given their price, and they seem identical to those I have from other sellers with a better reputation. Seben/Orbinar ships internationally, they have a lot of offers on ebay. Their Plössl cost around 9-16€ or so, 8-14£ I guess.

The problem with plössl eyepieces though is that the eye relief of those otherwise great eyepieces gets very short under 10mm. Some find 6.5mm still useable, so this might be the budget option.

Another is the 2x achromatic barlow for 13,50€/11£(?), actually this one was better then the Meade/Bresser barlow I got for 20€.

A barlow will decrease the contrast, it introduces chromatic aberation / color fringe to the system. But I find it still acceptable, and solves the issue with the short eye relief.

They also sell a 12mm erfle for 22€ (19£?) that has a bit short eye relief (the 8mm will probably too, but I don't have that; The 20mm has a nice longer eye relief).

The 12mm plus barlow may be a great combination for that type of telescope.

If you want to spend a bit more, the 6mm 66degree eyepiece can be bought for 23€ in china or 32€ (w/shipping) in the UK (27£), 40€ in germany.

http://m.ebay.de/itm/wide-angle-eyepiece-1-25inches-66-degree-F-6mm-/140717462903

It has some kidney beaning but I do not find it bothersome, works well when using the eyecup.

This is a wide angle eyepiece. The moon (almost) fits completely into view at over 100x.

Keep in mind planets will never appear huge, not even in a larger telescope due to seeing of the atmosphere. Galaxies will mostly remain faint smudges in the night sky, a larger 5-6" telescope (130£-230£ / 160-260€) will show a bit of detal in them, a 8" dobsonian (330€) will start to show spiral structures of some galaxies, individual stars of star clusters down to their center, and greater detail on planets, too...

So don't spend 200£ on eyepieces ;-) Save the money.

I observed a very long time with just three (halfway decent eyepieces) and that will show you a lot.

For the 76/700 this could be

-A 30-32mm Plössl or 20-25mm wide angle eyepiece to show more field of view, giving a better orientation and makes finding things via star-hopping easier

-A 12mm

-A 6mm or similar, or a barlow

So for now you could simply ad one eyepiece as you have two close to that, and add better ones laterr.

More magnification will rarely make sense with a small telescope like that, and adding more steps inbetween does not really enhance the experience.

For example, 70 and 80x will barely be different in both magnification and exit pupil (the amount/diameter of light exiting the eyepiece)

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I'm so happy I made an account here you guys are so quick and freaking awesome! I'll be sure to look into the book. Thanks everyone for the advice. It's stuff I was never able to find with just a Google search and now I really seeing myself pursing this hobby.

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Also, no it didn't come with a barlow lens and so far the only one I looked at was about 50 us dollars (I'm from Connecticut) so that will have to wait a bit.

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Welcome to SGL Mike some very good advice above. May I recommend Stellarium ( loads of people on here use it ).

It is a free download and I find it invaluable helping me locate various objects.

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Hi,

also check the used market here or in a US forum.

Again, plössl under 10mm have very short eye relief;
http://www.ebay.com/itm/Vixen-Optics-NPL-6mm-Plossl-Eyepiece-1-25-Super-Sharp-39202-/351143299518?pt=LH_DefaultDomain_0&hash=item51c1c589be
http://www.ebay.com/itm/NEW-6mm-Celestron-Plossl-telescope-eyepiece-/291219338810?pt=LH_DefaultDomain_0&hash=item43ce06763a



or as mentioned
http://www.ebay.com/itm/Achromatische-Barlow-Linse-BA2-2x-fuer-Teleskope-31-7mm-/200607942106
http://www.ebay.com/itm/Skys-the-Limit-1-25-2x-Achromatic-Barlow-Lens-Metal-Bodied-/380569583507?pt=UK_Telescope_Eyepieces&hash=item589bb6ff93

ATTENTION
I am not aware of import duties, taxes and the duty-free limit of small items over there, but if that is an option, There's probably a local source of these, they where sold under different lables/colors.
http://www.dutycalculator.com/new-import-duty-and-tax-calculation/ - seems like under $200 just some tax applies. Might depend on if you declare it as telescope eyepiece, microscope equipment or other optics, always worth looking into.
But check the official gov sites, too.

It's allways a good idea to buy locally... Especially if you can't wait to try it out :-)
I saw the 6mm 66degree eyepiece at a US telescope shop, but of course, twice as much as from the UK/three times as much as from china.

The better deal, as said, are the 6mm 66deg eyepieces. 116x is OK, not as dark and over magnified as the 4mm eyepieces often sold with these kits.
0,65mm exit pupil is also O.K., and if that's to dark on some faint objects, use the 10mm eyepiece.

according to http://www.dutycalculator.com/new-import-duty-and-tax-calculation/ the eyepiece from the UK http://www.ebay.com/itm/wide-angle-eyepiece-1-25inches-66-degree-F-6mm-/140717462903?pt=UK_Telescope_Eyepieces&hash=item20c36a1577 costs around US$46 ("Duty result is nil because the total value of the products does not exceed US$200.00") so same applies for the Plössl or barlow, though I would imagine there is a similar inexpensive source in the US (surplusshed.com? Craigslist?)

The 6mm 66deg costs around 30-36 dollars at Aliexpress, but of course you have to check the seller reputation and ideally use a prepaid credit card or so.

Also make sure the telescope is collimated, using a dust cap with a hole or 35mm film can.
At least the secondary mirror should not be completely off or the primary mirror tilted, etc.
(Prevent touchingthe surface, and even if, don't clean it though without reading a guide on how to clean telescope optics as the front surface mirror coatings are very delicate)

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Hi Mike, as you are in Connecticut, one of the best astronomy stores I have found is AgenaAstro here: http://agenaastro.com/  I have used them quite a bit this year and their service is efficient and very quick, they have some great stock too. They have some Agena dual ED 'StarGuider' eyepieces on sale for $60, and these have a 60 degree FoV and larger eye lenses, so very comfortable to look through, these are re-badged Astro-Tech 'Paradigms', well worth the money here: http://agenaastro.com/eyepieces/1-25-eyepieces.html

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