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Celestron 3X barlow just shows one big blur


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Hello everyone.

I would appreciate your input here as I'm guessing I bought an incompatible eyepiece for my Skywatcher N 130/650 although it could be that the eyepiece is faulty.

While it is a 1.25'' eypiece that fits perfectly well into my Skwatcher, whatever object I point it to (small, large, close, far) it's always shown blurry. I tried with both lenses that came with my Skywatcher (10mm & 25mm) and still the same.

The eyepiece I got is this one (Celestron 3x Barlow).

Thanks.

P.

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Are you getting a reasonable image with an eyepiece on its own ? when adding

the barlow you will need to refocus. You should see something recognisable.

If the view is blurry after careful focusing, you could be at too high a magnification,

especially the 10mm ep plus barlow.

Best regards, Ed.

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It is likely that you will have to re-focus with the Barlow in place (and an eyepiece in the Barlow). You may find that the focus position is quite different from using an eyepiece only. (Possibly too far for the focusser to cope, especially with a 3x Barlow.)

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You can only use the 25mm with the 3x barlow. Remember the smaller the eyepiece the more magnification. The 10mm won't work with a 3x barlow. So 25mm divide by 3 will give you roughly 8mm. I use a 10mm with a 2x barlow so that makes it a 5mm eye piece and its just about the useful magnification you can get from that scope. I have the same one. so basically next time you use your scope try the 3x barlow with the 25mm and make sure to focus it. It should work.

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That website looks decidedly dodgey as a source of respectable astronomy equipment. they claim:

"This economy Celestron Barlow triples (3x) the power of any telescope eyepiece it is used with" and "Works with all telescopes that have a 1.25" focuser"

Even with good gear this is sometimes stretching the limits of a scope/ep combo. And describing the housing as "Plastic" just isn't the kind of thing you'd see on credible kit. It may "fit" in a 1.25" focuser but there's no mention of scope or ep quality, focal lengths, number of elements, etc. Imho it's something you wouldn't worry about if the dog got hold of it.

Any half decent 2x barlow is gonna cost a min £60 new (maybe £40 s/h). Sorry to be negative but you'll like me in the end for being honest :)

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That website looks decidedly dodgey as a source of respectable astronomy equipment. they claim:

"This economy Celestron Barlow triples (3x) the power of any telescope eyepiece it is used with" and "Works with all telescopes that have a 1.25" focuser"

Even with good gear this is sometimes stretching the limits of a scope/ep combo. And describing the housing as "Plastic" just isn't the kind of thing you'd see on credible kit. It may "fit" in a 1.25" focuser but there's no mention of scope or ep quality, focal lengths, number of elements, etc. Imho it's something you wouldn't worry about if the dog got hold of it.

Any half decent 2x barlow is gonna cost a min £60 new (maybe £40 s/h). Sorry to be negative but you'll like me in the end for being honest :)

Have to agree I'm afraid :)

I strongly suspect that barlow is a non-achromatic one, ie: the lens is made of just one glass element rather than the two needed to give reasonable colour correction.

I think that the blurry image issue is, as Bizibilder suggests, that the Skywatcher scope can't bring it to focus - newtonians do have a limited focus range.

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Thanks for your replies everyone and yeap, I'm afraid I got too carried away by the eyepiece's price only to end up regretting it (although the name, 'Celestron', I considered to be somewhat reputable).

I've tried with the 25mm, in all possible focus levels and the result is still the same. So I can only conclude that what I bought is probably only good for the dumpster!

I'm thinking of trying my luck with this or this if anyone has any thoughts on them (although I'm guess the more expensive one probably means better).

Thanks again!

Regards,

P.

Edited by phoebus
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Yes - I too was dissapointed to see Celestron's good name against it. Teleskop Service do sell some good kit but you have to be pick'ey sometimes. The Celestron Ultima is worth looking at - so too is the Orion Shorty - both very popular here. Try a 2x before springing into higher powers - it's usually more than enough for most scopes. Antares also do a good 1.6x which I have. But for great reliable barlows the TV powermate is excellent - but very pricey - I also use the TV Big Barlow.

Hope that helps :)

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be careful not to use too much magnification. your scope has a usable magnification of maybe 22-200x although you might get a bit more in Cyprus.

this means a range from 30mm - 3.25mm in terms of eyepieces (EPs). If you have the 25mm and the 10mm (although I understand the supplied ones are not usually very good quality) you have (with the 2x barlow) 25mm, 12.5mm, 10mm and 5mm.

If you bought an 8mm Planetary as shown here 1.25" Eyepieces (either the Explorer or the TMB designed would be good) then you'd also have 8mm and 4mm. I'd suggest you will replace at least the 10mm with a better one once you look through this 8mm.

A better 2x Barlow may also help you too. Such as the Tal one.

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Thanks for your suggestion Moonshane. After checking out the link you suggested I am now intrigued by those 2 zoom eyepieces! :)

Could I expect the 7-21mm to work well with my setup? What about if I was also to combine it with a 2x barlow (or even 3x when I finally buy a decent one)?

Thanks!

P.

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Lots of good advice given here with not much left to say except, just because it says Celestron doesn't mean its genuine and with ebay especially there is always a peppering of fakes out there.

I'll tell you a short story...

I'm a Bushnell dealer and have been very impressed with the quality of their bino's. I saw a guy selling "Bushnell" at less than half the cost of trade at retail! They were so cheap I just couldn't believe it, so I purchased three pairs, different models from him.

When they arrived it was imediately obvious they were fake, flinsy packaging, cheap accessories and poor optics.

The moral of the story is if it looks too good to be true then it probably is!

If you buy genuine Celestron products from a company like FLO you KNOW you are getting the real deal at a fair price, on ebay you pay your money and take your chance! That said I have seen lots of kit sold by the big names on ebay at a good price so you just need to do your homework before you buy. Check out the feedback and how long they have been trading.

I have a Celestron 8mm X-Cel EP that cost me £70+ from FLO, yes I could have got it cheaper on ebay but is it worth the risk and disappointment.

You will learn to tell whats real and what's a toy with experience and as you can see if you post the details here BEFORE you buy, the guys and gals will keep you straight :)

Chalk it up to a bad experience and don't write off Celestron in a hurry. I really like my EP and barlow and can vouch for the quality of a genuine product.

Clear Skies.

Mark

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Thanks for your suggestion Moonshane. After checking out the link you suggested I am now intrigued by those 2 zoom eyepieces! :)

Could I expect the 7-21mm to work well with my setup? What about if I was also to combine it with a 2x barlow (or even 3x when I finally buy a decent one)?

Thanks!

P.

with the exception of the Hyperion zooms (approx £100 used) and the Nagler zooms from televue, others are often disappointing and I fear this one would be. in principle they seem a good idea but usually there are corners cut somewhere. personally I prefer fixed focal lengths although I do have the Nagler zoom which is superb on the moon (but at £300 new they should be). I still say stick with a 2x barlow.

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