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Celestron X-Cel LX 2x Barlow Lens 1.25"... ??

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#1 newtoskies

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Posted 18 January 2013 - 09:10 AM

I'm done with buying ep's for the time being and after getting good advice from a member here ( thanks Mike)I am looking into upgrading my 2x Barlow with a 3 element one. I don't have deep pockets so an expensive Barlow is out. I found the Celestron X-Cel LX 2x Barlow Lens 1.25" on Adorama for about $65.
My question is if this one is worth getting. I like the fact that it is 3 element and has the brass compression ring apposed to screws. it's also shorter than the one I have and beefier which makes handling easier in cold weather..ie cold fingers.

Your thought and opinions as always is greatly appreciated.

csrlice12, I see you have one or similar in your signature !

#2 Kon Dealer

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Posted 18 January 2013 - 09:48 AM

GSO 2.5X 1.25" Barlow is 3 element, with compression ring and is cheaper (and IMHO just as good).

#3 REC

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Posted 18 January 2013 - 09:51 AM

Sounds like a good one, but not sure your going to see much of a difference from the one you have now? Looks like you have a very good assortment of EP's now. You will like the ED's you have coming...nice EP's.

Bob

#4 csrlice12

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Posted 18 January 2013 - 09:54 AM

Agree with Kon Dealer, Barlows are pretty basic optical technonlogy. The Celestron X-Cel-LX is a nice barlow and is well worth the price; but most GSO/clones will work fine too (could even be the same mfg/eyepiece with a different label). One with ED glass might be a little bit brighter, but many use ED glass anymore anyways. If you are planning on AP though, a longer barlow would be best. The shorty ones will do fine for point&shoot and are excellent for visual, but for true AP, the longer ones work better.

#5 newtoskies

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Posted 18 January 2013 - 10:20 AM

Thanks fellas. No real AP in my future , just point and shoot camera or iPhone.
GSO's eh, will have to find a place that sells them on line.

#6 CosmoSat

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Posted 18 January 2013 - 12:16 PM

GSO 1.25" 2x Achromatic Barlow Lens

Clear Skies!

#7 newtoskies

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Posted 18 January 2013 - 12:34 PM

Is there a big difference in two and three element barlows ?

#8 GOLGO13

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Posted 18 January 2013 - 05:21 PM

you may want to show a picture of the one i gave you. i think the difference between that one and a 3 element may be less chromatic abberation introduced by the barlow. but it may be worth trying it out with your new scope to see how it performs. think that one was 30 bucks back when i got it. does it have a name brand on it? i think it was antares or something.

possible it wouldnt be too noticable between them. but it is important to consider the entire optical path. compression rings do rock in my opinion...but screws work also.

#9 newtoskies

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Posted 18 January 2013 - 06:00 PM

I had the scope out for about ten minutes, until my fingers froze. I only used the 9mm, 25 and 32 mm EP's. I have to leave soon so that was it for tonight. I didn't try out the barlow yet, just test fit it during the day. The one problem was that it went to far into the diagonal I I almost hit it with the barlow. Need to get used to that. Will post a first ( quick) light soon.

#10 newtoskies

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Posted 18 January 2013 - 06:07 PM

I'm holding off on getting the barlow until I use the one I have, but I think to avoid me damaging the diagonal I may just get it down the road. :question: :question:

#11 Jon Isaacs

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Posted 18 January 2013 - 07:05 PM

you may want to show a picture of the one i gave you. i think the difference between that one and a 3 element may be less chromatic abberation introduced by the barlow.


Barlows do not introduce chromatic aberration... Roland Christian of Astro-Physics has said many time that 2 element Barlows are "apochromatic." I never see an false color introduced by my favorite Barlows, 1.25 inch 2X Celestron Shorty's which were manufactured by GSO and if there were chromatic aberration to be seen, I have had them in situations where it would be apparent, high magnifications on Venus, high magnifications on double-stars.

Jon

#12 Gert K A

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Posted 18 January 2013 - 08:20 PM

Jon

let me draw on you wisdom yet again: What is it that makes up the price difference of around 3 to 4 times between the high end Powermate and the similar size GSO Barlow, how can the price difference be justified? Is there something not so obvious that I missed, is there may be a difference for use in AP?

I’m asking because two days ago I was almost getting the Powermate to check it out for myself, but realising I could get a 2x, 2.5x and a 5x GSO and still have money to spare I decided on the latter :scratchhead:

#13 GOLGO13

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Posted 18 January 2013 - 09:32 PM

Not sure if that's true with this barlow . Although I'm sure it's an OK one. It's a longer one which I believe has no name. Whether or not the quality would be as high as other barlows I don't know. It looked fine to me when I tried it out.

It could be an old cheap Orion one...not their shorty ones but their longer ones.

I think what you say is true, but it may depend on the quality of the barlow which is made. For instance, my Televue 3x barlow is a 2 element one. I don't think it has many aberrations. But that's Televue and not the cheapest ones being made.

Same thing can happen in eyepieces. I have some which seem to introduce aberrations like CA.

#14 GOLGO13

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Posted 18 January 2013 - 09:35 PM

I'm holding off on getting the barlow until I use the one I have, but I think to avoid me damaging the diagonal I may just get it down the road. :question: :question:


If it travels too far, you may want to use the set screw higher up and not let the barlow get that low. I actually have some eyepieces which I have to lift them up a bit to get them working (needs more out travel).

#15 WaterMaster

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Posted 18 January 2013 - 10:45 PM

Jon

let me draw on you wisdom yet again: What is it that makes up the price difference of around 3 to 4 times between the high end Powermate and the similar size GSO Barlow, how can the price difference be justified? Is there something not so obvious that I missed, is there may be a difference for use in AP?

I’m asking because two days ago I was almost getting the Powermate to check it out for myself, but realising I could get a 2x, 2.5x and a 5x GSO and still have money to spare I decided on the latter :scratchhead:


Here's what Al Nagler has to say about Barlows and Powermates.

#16 Gert K A

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Posted 19 January 2013 - 12:04 PM

Thank you Steve
Again the cliché “You get what you pay for” seems to hold up. There are no shortcuts :bawling:

#17 newtoskies

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Posted 19 January 2013 - 12:30 PM

Thanks all for the great info and the link. I haven't checked the brand of the barlow I have but will later. I am considering the mentioned Celestron barlow and a GSO barlow. Yes you get what you pay for, but budget plays a big role in what I can buy. I'd like to get all the ep's, RACI and Barlow that I need at the moment...then I will hold off on buying anything else. I'd like to use what I have and learn about the new scope and how to get the best use out of everything.No sense in spending a fortune on all the goodies, and not know how to use them.

#18 Jon Isaacs

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Posted 19 January 2013 - 12:50 PM

Thank you Steve
Again the cliché “You get what you pay for” seems to hold up. There are no shortcuts :bawling:


The question is not whether you get what you pay for but rather whether what you are getting is something you need. The Powermate is useful with long focal length eyepieces where a standard Barlow might Vignette or the increased eye relief might represent an issue.

If you are using a Barlow with shorter focal length eyepieces, these are non-issues. Myself, I use Barlows only with shorter focal length eyepiece when I need magnifications that are higher my shortest focal length eyepieces can provide. For this, a simple 2 element Barlow is just fine.

Jon

#19 Dave Mitsky

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Posted 19 January 2013 - 01:04 PM

you may want to show a picture of the one i gave you. i think the difference between that one and a 3 element may be less chromatic abberation introduced by the barlow.


Barlows do not introduce chromatic aberration... Roland Christian of Astro-Physics has said many time that 2 element Barlows are "apochromatic." I never see an false color introduced by my favorite Barlows, 1.25 inch 2X Celestron Shorty's which were manufactured by GSO and if there were chromatic aberration to be seen, I have had them in situations where it would be apparent, high magnifications on Venus, high magnifications on double-stars.

Jon


Al Nagler said the same thing some years ago regarding three lens-element "apochromatic" Barlow lenses back when the Tele Vue web site had a Q and A section.

Dave Mitsky

#20 newtoskies

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Posted 19 January 2013 - 01:14 PM

If you are using a Barlow with shorter focal length eyepieces, these are non-issues. Myself, I use Barlows only with shorter focal length eyepiece when I need magnifications that are higher my shortest focal length eyepieces can provide. For this, a simple 2 element Barlow is just fine.



Jon, this is basically what I would need one for as well. So then a 2 element barlow will work just fine for me. The one I have does work great, especially in my dob, but I don't want to take changes and damage my Refractors diagonal.

#21 howard929

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Posted 19 January 2013 - 01:35 PM


If you are using a Barlow with shorter focal length eyepieces, these are non-issues. Myself, I use Barlows only with shorter focal length eyepiece when I need magnifications that are higher my shortest focal length eyepieces can provide. For this, a simple 2 element Barlow is just fine.



Jon, this is basically what I would need one for as well. So then a 2 element barlow will work just fine for me. The one I have does work great, especially in my dob, but I don't want to take changes and damage my Refractors diagonal.


Does that Barlow have set screws that have you concerned? The diagonal you have won't notice them if it is. Just the eyepieces that your already have been using them with. Still. Your call.

#22 newtoskies

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Posted 19 January 2013 - 02:10 PM

Does that Barlow have set screws that have you concerned



Not quite sure what you mean, but no I didn't see any other screw on the barlow except the one that secures the ep. I will try to get a pic up of the barlow. BTW., there is no name brand on this one, it just says 2x Barlow lens.

#23 howard929

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Posted 19 January 2013 - 02:22 PM


Does that Barlow have set screws that have you concerned



Not quite sure what you mean, but no I didn't see any other screw on the barlow except the one that secures the ep. I will try to get a pic up of the barlow. BTW., there is no name brand on this one, it just says 2x Barlow lens.


How is it going to damage your diagonal?

#24 newtoskies

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Posted 19 January 2013 - 02:45 PM

It goes too far into the diagonal and hits the mirror....bottoms out in other words. I have to head out for a couple of hours but will get a pic of the barlow up later. It could also be that I am very new to refractors and diagonals and don't know what the heck I'm doing..lol

#25 howard929

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Posted 19 January 2013 - 02:53 PM

But hey. Here's what happened to me.

Just starting out I bought a used 2x 1.25" Barlow off a nice gent around here for $11. At the time I thought it was really great.

Jumping forward to better times I bought the GSO Barlow in my sig line and between them there's no comparison. The older one I use just for barlowing my laser.






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