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VITE 2X Barlow Lens Review

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#1 jfriz

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Posted 11 November 2016 - 08:05 AM

This review describes the VITE 2x Barlow lens including my initial impressions of build and optical quality. I observe from a suburb in the southeast U.S. I have one telescope, an 8-inch Dobsonian, and have had it for approximately five years. The photos included in this review represent my first crack at astro-imaging. I wanted to try prime focus photography with my DSLR but my focuser does not have enough in-travel to do so. I used the Barlow to achieve focus with my telescope/focuser/camera combination.

Click here to view the article
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#2 CQDDEMGY

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Posted 11 November 2016 - 11:52 PM

Thank you for the review.



#3 EJay

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Posted 14 November 2016 - 12:31 AM

Thanks for the review. I bought one of these a while back and have a positive opinion but haven't really compared it to anything else. 



#4 TOMDEY

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Posted 14 November 2016 - 10:26 AM

Interesting; I'm especially glad that you dismembered it so we can see what's inside! I needed a 1.1x Barlow (not available), so bought a bunch of used stock Barlows to examine. Most all are simple, cemented negative achromatic doublets. Yours is of that type. And, like yours, most have that screw-off lens cell. I then worked out the 1st order optical formulae (I'm a retired optics guy) to relate spacing to amplification. I was able to reconfigure a regular Barlow into a "shorty" tube to render it "weaker." But that still did not get me the extremely mild 1.1x that I needed. Finally found the glass I needed in an obscure "new old stock" optics house on the West Coast. An aerospace buddy tipped me off to that source. They even coated it for me!  And a friend down the road built the mount in his machine shop. I paid him with a batch of cookies that my wife made. Thanx for the nice article.  Tom Dey


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#5 Karl Fabian

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Posted 17 November 2016 - 12:31 AM

I bought a Vite so called "5x Apo" barlow more out of curiosity and  took a chance due to the extremely low price of $15 shipped free direct from China. (Ebay purchase and lots of vendors selling this item on Amazon also at the time). Wasn't expecting much and sure enough my expectations were met and then some.  For one thing it is not 5x but 3x. Used with any eyepiece only the very center of the heavily vignetted field is sharp and becomes increasingly blurred and astigmatic away from the center in addition to severe lateral color. The unit is one solid HEAVY metal assembly and the lens assembly appears to be permanently mounted screwed or possibly pressed in to the bottom of the thick heavy barrel. The 15mm lens assembly WILL NOT unscrew even using channel lock pliers! This so called "5x apo barlow is more than likely not even a barlow but probably a re-purposed negative lens assembly meant for another application, and re-machined into a device that looks like a barlow lens with a sloppy fitting  barrel for your eyepiece. The glass looks good with a nice green apparently multicoated surface. The unit may have a qualty lens but whatever it is it is absolutely worthless as a barlow. The 2x looks to be OK  but stay away from the so called "3 element 5X apo" barlow. They are also selling it under other names. WORTHLESS JUNK      https://www.amazon.c...d/dp/B00NG61JIW


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#6 LennyM

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Posted 05 December 2016 - 08:06 AM

In many cases once a short barlow exceeds 2x, (3x to 5x) the optical path becomes exceedingly steep and thus distortion is the result.   For any barlow with a factor greater that 2x, I would recommend going with a longer configuration.   



#7 CzechAstronomer

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Posted 09 December 2016 - 12:15 PM

Interesting; I'm especially glad that you dismembered it so we can see what's inside! I needed a 1.1x Barlow (not available), so bought a bunch of used stock Barlows to examine. Most all are simple, cemented negative achromatic doublets. Yours is of that type. And, like yours, most have that screw-off lens cell. I then worked out the 1st order optical formulae (I'm a retired optics guy) to relate spacing to amplification. I was able to reconfigure a regular Barlow into a "shorty" tube to render it "weaker." But that still did not get me the extremely mild 1.1x that I needed. Finally found the glass I needed in an obscure "new old stock" optics house on the West Coast. An aerospace buddy tipped me off to that source. They even coated it for me!  And a friend down the road built the mount in his machine shop. I paid him with a batch of cookies that my wife made. Thanx for the nice article.  Tom Dey

you seem very experienced! 

 

For what purpose do you need exaclly 1.1x magnification? I cant tell the difference between 125x and 140x. :D well, i can, but it is really minor. 


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#8 Waldemar

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Posted 15 December 2016 - 05:47 AM

 

Interesting; I'm especially glad that you dismembered it so we can see what's inside! I needed a 1.1x Barlow (not available), so bought a bunch of used stock Barlows to examine. Most all are simple, cemented negative achromatic doublets. Yours is of that type. And, like yours, most have that screw-off lens cell. I then worked out the 1st order optical formulae (I'm a retired optics guy) to relate spacing to amplification. I was able to reconfigure a regular Barlow into a "shorty" tube to render it "weaker." But that still did not get me the extremely mild 1.1x that I needed. Finally found the glass I needed in an obscure "new old stock" optics house on the West Coast. An aerospace buddy tipped me off to that source. They even coated it for me!  And a friend down the road built the mount in his machine shop. I paid him with a batch of cookies that my wife made. Thanx for the nice article.  Tom Dey

you seem very experienced! 

 

For what purpose do you need exaclly 1.1x magnification? I cant tell the difference between 125x and 140x. :D well, i can, but it is really minor. 

 

I would think adding another piece of glass to get so little gain, only adds more problems, no ?


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#9 overnight

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Posted 25 January 2017 - 12:11 AM

I bought this barlow, and I think it is way more sturdier than the Celestron Omni 2x barlow. It looks high quality, but it gives objects a red tint compared to the Omni. I don't know if it is the affect of adding APO coatings.



#10 Karl Fabian

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Posted 27 January 2017 - 12:17 PM

I bought a Vite so called "5x Apo" barlow more out of curiosity and  took a chance due to the extremely low price of $15 shipped free direct from China. (Ebay purchase and lots of vendors selling this item on Amazon also at the time). Wasn't expecting much and sure enough my expectations were met and then some.  For one thing it is not 5x but 3x. Used with any eyepiece only the very center of the heavily vignetted field is sharp and becomes increasingly blurred and astigmatic away from the center in addition to severe lateral color. The unit is one solid HEAVY metal assembly and the lens assembly appears to be permanently mounted screwed or possibly pressed in to the bottom of the thick heavy barrel. The 15mm lens assembly WILL NOT unscrew even using channel lock pliers! This so called "5x apo barlow is more than likely not even a barlow but probably a re-purposed negative lens assembly meant for another application, and re-machined into a device that looks like a barlow lens with a sloppy fitting  barrel for your eyepiece. The glass looks good with a nice green apparently multicoated surface. The unit may have a qualty lens but whatever it is it is absolutely worthless as a barlow. The 2x looks to be OK  but stay away from the so called "3 element 5X apo" barlow. They are also selling it under other names. WORTHLESS JUNK      https://www.amazon.c...d/dp/B00NG61JIW

Update: Got it apart and examined (Had to pry off pressed on end cap)..This barlow has been falsely advertized as "5X Apo". The Chinese translation of 5X Apo translates to common English as: "2 simple cheap single element negative lenses stacked and spaced to give 3X with severe aberration and color error ".  Beware of anything marketed as Vite is my word of caution. All they are is a marketing entity. 



#11 Gipht

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Posted 05 March 2017 - 09:50 AM

Is there a  thread on this site  that discusses  Barlow vs Projection  for AP?  My experience  so far has favored the projection eyepieces, but I am interested  in hearing what other more experienced people have to say.



#12 overnight

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Posted 05 March 2017 - 05:29 PM

Is there a  thread on this site  that discusses  Barlow vs Projection  for AP?  My experience  so far has favored the projection eyepieces, but I am interested  in hearing what other more experienced people have to say.

 

First of all, this is not the thread to ask that question. It would be better for you to make a separate post in another place (Beginning and Intermediate AP forum) ; this place is only for discussion on the Vite 2x barlow lens.

 

There is no "Barlow vs Projection" stuff on AP. I think you mean prime focus vs afocal. Almost all serious APers like myself use prime focus astrophotography. Sometimes a 2x Barlow, focal reducer, or field flattener is needed. It all depends on your scope on whether you can reach focus with your camera or not, or has optical issues.



#13 nicknacknock

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Posted 06 March 2017 - 06:04 AM

Is there a  thread on this site  that discusses  Barlow vs Projection  for AP?  My experience  so far has favored the projection eyepieces, but I am interested  in hearing what other more experienced people have to say.

 

Hi Gipht,

 

The best way is to actually start a topic on this issue in Beginners Astrophotography. I am sure you'll get a ton of help and even more opinions there grin.gif



#14 Adun

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Posted 15 March 2017 - 06:04 PM

I got a a Vite 2x barlow today from AliExpress (the smaller version that screws on an eyepiece).

 

Tested it on the C90 during daylight and seem to work fine, 2x indeed.

 

Next good night I get I'm going to test it on a 450mmFL F4 newtonian to see how it performs.



#15 Adun

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Posted 02 April 2017 - 01:47 AM

Update: I tested the VITE 2x Barlow on a short, 114mm x 450mm F4 newtonian, at Jupiter with an 8-24mm zoom and a 10mm eyepiece, and tried to compare the view with the same eyepieces on the 1250mmFL C90 (non barlowed).

 

The barlow worked well, however, at the highest magnification there was a bit of chromatic aberration in the edges of Jupiter, maybe a mix of "too much glass" between the barlow and the zoom.

 

Overall I'm pleased with this little barlow for both kids scopes.



#16 overnight

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Posted 03 April 2017 - 12:24 PM

Its no longer on sale, only ones left are "SVBONY", which an earlier commenter noted is worthless junk. Stick with what you know is going to be good quality.



#17 TOMDEY

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Posted 19 April 2017 - 06:47 AM

 

Interesting; I'm especially glad that you dismembered it so we can see what's inside! I needed a 1.1x Barlow (not available), so bought a bunch of used stock Barlows to examine. Most all are simple, cemented negative achromatic doublets. Yours is of that type. And, like yours, most have that screw-off lens cell. I then worked out the 1st order optical formulae (I'm a retired optics guy) to relate spacing to amplification. I was able to reconfigure a regular Barlow into a "shorty" tube to render it "weaker." But that still did not get me the extremely mild 1.1x that I needed. Finally found the glass I needed in an obscure "new old stock" optics house on the West Coast. An aerospace buddy tipped me off to that source. They even coated it for me!  And a friend down the road built the mount in his machine shop. I paid him with a batch of cookies that my wife made. Thanx for the nice article.  Tom Dey

you seem very experienced! 

 

For what purpose do you need exaclly 1.1x magnification? I cant tell the difference between 125x and 140x. laugh.gif well, i can, but it is really mino

Sorry for the delay: A barlow does two, potentially-useful 1st-order things: 1) increases magnification, 2) displace the image back away from where it is... generally considered to be a bad thing. In my case, my nice Night Vision Eyepieces couldn't reach focus... too far out. So, I could either modify the mechanicals to move the eyepiece in and/or focus out ~or~ modify the optics to move the image out. I chose the 2nd option, and it worked MAGNIFICENTLY! The instrument is my JMI 16-inch binoculars. The mild barlows pop in and out Very Easily, from inside the OTAs, between the folding flats. This renders my Night Vision parfocal with the 24mm Panoptics and close to the same mag = "magnificent." Regarding the other question about higher-order effects on imagery: At a mild 1.1x, and pretty far from the image, the rays aren't "bent" much at all. So (believe it or not!), a simple, bent singlet performs just fine. It is a bent, thin meniscus... so the two surfaces share the ray-bending, which minimizes the spherical aberration and chromatic contributions. All I can say is - the performance is great!  Tom Dey


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#18 TOMDEY

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Posted 19 April 2017 - 07:18 AM

I just entered a comment regarding Very Mild Barlow and why this could be useful. That prompts a general comment regarding the mystique of barlows, in general. We, almost always, use barlows to boost magnification. Most comprise cemented achromatic doublets; some get fancier than that. "Shorty" barlows bend the rays more, so tend to degrade the image more. Barlow amplification depends on the spacing to the eyepiece field stop... closer is less, farther is more. THIS is why e.g. a "2X" barlow is rarely exactly 2X... it depends on which eyepiece you are using it with. Regular barlows also push the exit pupil back, away from the eyepiece. This can be bad, especially with Wide Field eyepieces, can vignette the field. But THAT effect is often mollified/mitigated, because the increased F# stresses the eyepiece less! The TeleVue PowerMate addresses/corrects this effect. The best barlows are designed for one eyepiece only. Nagler eyepieces can be thought of in that sense. The negative group at the bottom may be thought of as a custom barlow that is optimized as a dedicated part of the entire eyepiece. The One Remaining unknown, out of control of the designer... is What Telescope will this barlow, eyepiece be used with? And THAT is why Eyepiece Reviews often (and correctly) report differently. e.g. A Big, fast DOB will love/need Naglers; a good SCT will work with most any eyepiece, but loves the long Panoptics. The very best design/build are where all the optics are optimized and dedicated together. That's why I like the Zeiss binoculars. ~end bloviation~  Tom Dey



#19 K4PDM

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Posted 20 April 2017 - 06:24 AM

I probably should chime in here about the Vite/Svbony barlow, even though I started another thread on a similar subject.

The barlow has much improved the views through my inexpensive eyepieces, and I have found that a cheap 25mm plossl and the cheap Vite barlow gives a better image than my cheap GSO 12mm eyepiece on the planets.

 

I can endorse this barlow for those of us on a budget even though I don't have a better one to compare it with. It certainly will work for some of us until we can upgrade.




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