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GlennLeDrew
sage
Reged: 06/18/08
Posts: 286
Loc: Ottawa, Ontario, Canada
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Back in the early- to mid-nineties I purchased a pair, and still have them. Before that I'd never owned a Galilean type optic. (You know, the type which uses negative lenses for eyepieces and hence generally offer *very small* apparent fields of view.)
Well, with this little Russian beauty, the small field blues are negated by using the combination of short f/ratio objectives and strongly curved oculars. As with any Galilean instrument, the field of view is determined by the apparent angular diameter of the objective as seen through the eye lens. So the Owl eyes' wide objective allows a generous field such as I've never seen in any other "opera glass."
As marked on the instrument, the field is purported to be 28 degrees. As-is, I measured it closer to 18 degrees. For the longest time, therefore, I thought it was simply a typo. Experiments with positive/negative lens combinations revealed that the closer one's eye was to the eye lens, the larger the field of view. After fiddling around to see what could be done to enlarge the field, I found that the black "back plate" on the rear of the eyepiece, which has the hole one looks through, could be threaded off. With it removed, one's eye could get rather closer to the eye lens and hence enjoy a larger. NOW I get close to the advertised 28 degrees, and can just fit in the view the entire Big Dipper!
It's been so long now since I did this that I just can't remember... with the "back plate" removed, the eyepiece *may* be able to fall out. At any rate, whether to also keep it in place, I did wrap electrical tape around the exterior of the eyepiece housing mainly to keep the focus set.
An oddity I've discovered about my eyes is that I can relax them and to a significant degree focus "beyond infinity" (no Buzz Lightyear jokes, please!). It's like being presbyopic, or far-sighted. As a result, I tend to focus any instrument with the oculars moved farther back, which results in a slight increase in magnification. It just might be the case that for me, my Owl eyes work at closer to 2.5X (I should measure this, eh, Edz?). If so, this would correspond to a light gathering power of a factor of ~6, or nearly 2 magnitudes, assuming no significant light loss. Where I often observe from, my nelm is typically 6.4m. So the Owl Eyes should allow me to see down to ~8.3m.
If we use the naive calculation: Afov = Tfov x mag., we have Afov = 28 x 2.5 = 70 degrees. (Or perhaps closer to 64 degrees if the working mag. is indeed 2.3X.) Not bad, indeed! I should point out that because the "field stop" is the very out-of-focus image of the objective's edge, there is no nice and sharp black circle framing the view. But this is always the case for opera glasses.
About the optics themselves. I was quite surprised at their sophistication! The objective is an air-spaced two-element job. But I really can't recall if the ocular has one or two elements. All surfaces are coated, and have the typically Russian mauve/purple/tan color cast.
To get a symmetrically sharp image, centering of the eyes is rather critical, due mainly to the steeply curved oculars. But once achieved, the views are really quite nice! Due to the necessity of accurate eye centration, it's pretty much pointless trying to evaluate off-axis sharpness, as the test is effectively rendered invalid due to the now-incorrect pupil position. At any rate, when looking toward the field center, the peripheral sharpness as perceived by the off-axis retina is fully satisfactory in my opinion. And given that this is fundamentally an almost ancient design--albeit modernized--this is no mean feat considering the steeply curved elements.
One last point. The odd, ground surface at the back end of the eyepieces was an annoying source of scattered light. To get around this I used a very fine brush to cover it over with flat black paint. Highly recommended!!
I don't ever plan on parting with mine, unless something even better comes down the pike.
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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Vincent33
member
Reged: 09/18/07
Posts: 95
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Quote:
I really can't recall if the ocular has one or two elements
Here is the optical schematics (is it the right term?):
http://www.kasai-trading.jp/widebino28.htm
Bye.
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holger_merlitz
sage
Reged: 02/08/04
Posts: 281
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Which is apparently a Gauss-type objective design.
Cheers,
Holger
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StarStuff1
sage
Reged: 04/01/07
Posts: 359
Loc: East Tennessee
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Don't know if this has been answered before but I measured the exit pupil of my Russian 2.3X40s and found it to be around 8.5mm. I say "around" because there is no hard field stop. If the objective is 40mm and the actual magnification is 2.3X shouldn't the exit pupil be 17.4mm?
BTW I,ve had these about 12 years and still like them.
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Two dozen eyepieces, a dozen binoculars, a half dozen refractors, two reflectors and a homemade Image Intensifier Eyepiece (IIE). All products subject to change by the owner at any time.
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GlennLeDrew
sage
Reged: 06/18/08
Posts: 286
Loc: Ottawa, Ontario, Canada
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Quote:
Don't know if this has been answered before but I measured the exit pupil of my Russian 2.3X40s and found it to be around 8.5mm. I say "around" because there is no hard field stop. If the objective is 40mm and the actual magnification is 2.3X shouldn't the exit pupil be 17.4mm?
A Galilean system has no exit pupil as such. However large is the eyepiece's aperture, that is the diameter of the "exit pupil". The 8.5mm you measure is the clear aperture of the eyepiece's rear element (I think, and will have to check). At any rate, this clear aperture was clearly chosen because virtually no one's pupils expand larger. Moreover, because the observer's pupils must be well centered on-axis for good performance, the smaller eye lens ensures that this is more easily achieved.
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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StarStuff1
sage
Reged: 04/01/07
Posts: 359
Loc: East Tennessee
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Thanks, Glenn. I didn't know that about Galilean optics. Kinda makes sense. I did a quick and dirty measurement with a plastic ruler or the ep rear element and it looks very close to 8.5mm.
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Two dozen eyepieces, a dozen binoculars, a half dozen refractors, two reflectors and a homemade Image Intensifier Eyepiece (IIE). All products subject to change by the owner at any time.
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Swedpat
Pooh-Bah
Reged: 02/18/05
Posts: 1006
Loc: Boden, Sweden, Scandinavia
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Let me ask: what the meaning with a 2,3x binocular? You will hardly experience a magnification at all. Of course it's better than the naked eye but...
It seems to be a serious instrument and not a toy, however. I would like to try one... ;-)
Regards, Patric
--------------------
*2,3x40 Constellation View Wide-Bino
*Leica Ultravid 8x20 BR
*Leupold 6x30 Yosemite
*Leupold Katmai 6x32
*Swarovski SLCNew 7x42B
*Bresser (Lidl) 10x50
*Oberwerk 11x70
*No name (Kunming) 15x70
*Scopos ED APO 66
*Celestron Accessory kit, Vixen LV 20,10,5mm
Psalm 19:2
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CESDewar
GorillAstronomer
Reged: 01/16/05
Posts: 1679
Loc: Morganton, GA, USA
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I bought a pair of these, largely on a whim, because they seemed unusual and interesting.
I actually find them quite useful on nights of really poor transparency or when the moon is out. I am so used to 6+ mag skies that I uhhh get a bit disoriented when I can't even quickly pick out the Hercules keystone. But with these binoculars, you pick up at some two magnitudes or so - enough to quickly re-orient. I often position my scopes with a Green laser, and a quick view throuh these binoculars makes it possible to more accurately position the laser.
Anyway, as I mentioned about the Miyauchi 5x32's, these are very specialized binoculars - not a second or even third pair, but for us binoholics on this forum, definitely a fun addition.
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GlennLeDrew
sage
Reged: 06/18/08
Posts: 286
Loc: Ottawa, Ontario, Canada
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Swedpat,
Indeed, 2.3X sounds like so little. But it really does fill in a gap between naked eye and typical bino magnifications. And they do deliver at least a 1.5 magnitude gain, while providing a field large enough to take in the smaller constellations in their entirety (more so if you take off that rear perforated eyepiece cover which keeps your eyes too far back.)
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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Vincent33
member
Reged: 09/18/07
Posts: 95
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I can't do any better than recall a post on these binoculars here by StarStuff1 (found with Google) on Jan 4, 2006 (that post helped me to purchase them):
===
These are not a new product. I bought the Russian version of these about 12 years ago, They too were advertised as having 28° tfov. In actuality they were closer to 24-25° tfov. Some might think that at 2.3X you would not see much but that person would be wrong. Get the inter-pupillary distance right, focus for each eye and BANG, supervision. Whole constellations in the fov like all of Cygnus. Marvelous for the Milky Way on a dark, clear night.
===
Bye.
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Swedpat
Pooh-Bah
Reged: 02/18/05
Posts: 1006
Loc: Boden, Sweden, Scandinavia
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Glenn,
Since several years I have a Bushnell X-wide 5x25 which I bought just because I liked the idéa of a real wide field and stable image binocular. I also liked the idéa of taking in entire consellations in the FOV. The X-wide 5x25 has around 13deg FOV.
BUT:
The FOV is sharp to only about 50% (6-7deg) and further towards the edges the image is strongly distorted. That means it's sharp of only approximately 25% of the total field area...
The internal reflexions and ghost images are extreme as well.
These factors make the X-wide 5x25 hardly useful for astronomy at all.
But when it comes to magnification I noticed following: The first impression with 5x (actually I have noticed that the true magnification is closer to 4-4,5x because the exit pupil is undoubtly larger than 5mm) was that it felt like I don't came much closer than the naked eye view. When looked at cars I could easy read licence plate numbers at several times the distance as with the naked eye, however.
It's the same thing with higher powered glasses: it's an optical illusion that makes we don't experience we come that closer as the magnification states. Putting a 10x binocular to my eyes it feels like maybe 5x closer, not more. But when trying to se details it's obvious the magnification really visibly locates me that closer as the magnification rate.
Therefore I realize that even a low power of 2,3x will help me to see details significantly better than with naked eye, though the very first impression likely will be that I will doubt there is any magnification at all!
Do you have a recommendation where to order the 2,3x40? I have not found a dealer in my country.
Excuse my faulty english, these are quite complicated sentences for me...
Regards, Patric
--------------------
*2,3x40 Constellation View Wide-Bino
*Leica Ultravid 8x20 BR
*Leupold 6x30 Yosemite
*Leupold Katmai 6x32
*Swarovski SLCNew 7x42B
*Bresser (Lidl) 10x50
*Oberwerk 11x70
*No name (Kunming) 15x70
*Scopos ED APO 66
*Celestron Accessory kit, Vixen LV 20,10,5mm
Psalm 19:2
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KennyJ
Reged: 04/27/03
Posts: 9960
Loc: Lancashire UK
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Patric ,
Once again , no need to excuse your faulty English .
Your posts always make more sense to me than many of my own , when I read them over again :-)
I've had a theory for several years now with regard to the optical illusion of objects not appearing as magnified as they truly are .
When we see , naked eye , for example a HOUSE FOR SALE sign against the background of the windows of the house , which appear to be the same apparant size as the sign .
When we look at the sign through 10x binoculars , the background window is also magnified 10x , as is everything else in the field of view ( or at least approximately so )
This has the effect of neutralising the actual enlargement .
In my example , if we could just magnify the sign , and nothing else , then we would easily see that the sign appeared 10x larger .
It's all about perspective -- as in the famous horizon moon ( and setting sun ) illusion !
Now the moon , when NOT on the horizon , is actually one of the very rare exceptions to situations where the above perspective theory applies .
Usually , when we view the moon , it against only perhaps a few visible stars , which do NOT appear any LARGER when viewed through binoculars , but they DO appear further separated than they did naked eye .
In this case , we should revert to EASILY seeing that the moon , through 10x binoculars , appears 10x larger ( or closer ) -- BUT -- I , for one , do NOT !
To my eyes ( or rather via my brain ) I get the optical illusion of the moon , when magnified by 10x , APPEARING to be magnified by a factor as if dividing 10 by pi ( 3.142 ).
In other words , if I had to GUESSTIMATE the apparant size of the moon , viewed through binoculars which were truly 10x magnification , but the magnification of which was kept secret from me , whilst not permitted to compare with one eye naked and the other through an eyepiece , I would be inclined to GUESS that the magnification was 10 / 3.142 or 3.182x APPARANT .
All of the above , of course , is a great example of how many of my posts can appear far more nonsensical than any of YOURS , in spite of your supposed language disadvantage ! :-)
But - it was something to think about on a lazy , damp , overcast , windy sunday afternoon !
Kind regards
Kenny
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Two eyes and a preference to use both
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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Swedpat
Pooh-Bah
Reged: 02/18/05
Posts: 1006
Loc: Boden, Sweden, Scandinavia
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Hi Kenny,
Yes I remember we have earlier some year ago discussed this issue. Looking through a binocular, with for example 10x power, will not produce the FEELING of the objekt beeing 10x larger than the naked eye view. But try to read for example a licence plate of a car with 10x (providing the image is stable), you will then see that you can read it at much longer distance than 3.182 times as you can with naked eye. I realized that I could read licence plates with the Bushnell 5x25 of at least 3-4 times longer distance than naked eye, though the feeling of the image scale was maybe twice in comparison to the naked eye.
This means that the details possible to see with the 2,3x40 will be likely about twice than the naked eye (if taking in consider that any binocular actually will provide a worse image than the naked eye). And twice the resolution is comparable to the difference between 10x and 20x magnification of an optical glass. Which is very significant.
Regards, Patric
--------------------
*2,3x40 Constellation View Wide-Bino
*Leica Ultravid 8x20 BR
*Leupold 6x30 Yosemite
*Leupold Katmai 6x32
*Swarovski SLCNew 7x42B
*Bresser (Lidl) 10x50
*Oberwerk 11x70
*No name (Kunming) 15x70
*Scopos ED APO 66
*Celestron Accessory kit, Vixen LV 20,10,5mm
Psalm 19:2
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StarStuff1
sage
Reged: 04/01/07
Posts: 359
Loc: East Tennessee
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Hi Swedpat,
The only place selling these new I am aware of is Blue Planet Optics
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Two dozen eyepieces, a dozen binoculars, a half dozen refractors, two reflectors and a homemade Image Intensifier Eyepiece (IIE). All products subject to change by the owner at any time.
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KennyJ
Reged: 04/27/03
Posts: 9960
Loc: Lancashire UK
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Patric ,
Another point I know I've made before , but which has just sprang back to mind following a co -incidental PM exchange , is not to forget that when magnified 10x , any object's apparant area is increased not by 10x , but by 100x .
That is to say , if it took one tin of paint to cover what is seen naked eye , to cover the same object as seen magnified through a 10x instrument would require 100 tins of paint of the same size , not 10 tins !
Kenny
--------------------
Two eyes and a preference to use both
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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Swedpat
Pooh-Bah
Reged: 02/18/05
Posts: 1006
Loc: Boden, Sweden, Scandinavia
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Thanks Starstuff for the info.
These small glasses are quite cool. I am just imaging visiting a starparty or birdparty with them among large astrobino-users or Zeiss-Swarovski-and Leica-snobs! (I don't belong to the snobs even if I have a Swarovski... 
Then I can smile and say: "how many birds do you get into the field?" or: "no need for tripod-mounting here!) 
Regards, Patric
--------------------
*2,3x40 Constellation View Wide-Bino
*Leica Ultravid 8x20 BR
*Leupold 6x30 Yosemite
*Leupold Katmai 6x32
*Swarovski SLCNew 7x42B
*Bresser (Lidl) 10x50
*Oberwerk 11x70
*No name (Kunming) 15x70
*Scopos ED APO 66
*Celestron Accessory kit, Vixen LV 20,10,5mm
Psalm 19:2
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Swedpat
Pooh-Bah
Reged: 02/18/05
Posts: 1006
Loc: Boden, Sweden, Scandinavia
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Yes Kenny, it's quite fantastic that 10x actually will results in 100x the area of the observed object!
That's also the reason that the relative brightness of an optical instrument will be 100x less if increasing the magnification to 100x in comparison to 10x. The same light amount will be spread over 100 times larger area.
Regards, Patric
--------------------
*2,3x40 Constellation View Wide-Bino
*Leica Ultravid 8x20 BR
*Leupold 6x30 Yosemite
*Leupold Katmai 6x32
*Swarovski SLCNew 7x42B
*Bresser (Lidl) 10x50
*Oberwerk 11x70
*No name (Kunming) 15x70
*Scopos ED APO 66
*Celestron Accessory kit, Vixen LV 20,10,5mm
Psalm 19:2
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Vincent33
member
Reged: 09/18/07
Posts: 95
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Quote:
Do you have a recommendation where to order the 2,3x40? I have not found a dealer in my country.
I bought them in Hungary, here is the link:
http://www.tavcso.hu/binokularok.php
now they are about 50 Euro: I paid more, when I did ... :-(
Bye.
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davidmcgo
sage
Reged: 10/09/04
Posts: 427
Loc: San Diego, CA
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These might even serve as binocular "doubler" if you held them up behind the eyepieces of a large tripod mounted binocular?
Zeiss, Swarovski, and others sell small 2x or 3x monocular attachments for their high end binoculars to get higher power out of one side and these look less expensive.
Dave
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GlennLeDrew
sage
Reged: 06/18/08
Posts: 286
Loc: Ottawa, Ontario, Canada
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Quote:
These might even serve as binocular "doubler" if you held them up behind the eyepieces of a large tripod mounted binocular?
Dave
The field of view offered by this combination would most probably be awfully small, much less than the front binocular's apparent field. In a Galilean system the entrance pupil is still the eye, which here would be quite far behind the big bino's exit pupil.
The best auxilliary scope would therefore be one with a positive eyepiece, because then the entrance pupil will be the objective itself, which can be placed properly in plane with the front bino's exit pupil. This will allow to see an image across the aux 'scope's full field, and not just a small part in the center. And of course, for right side up viewing, the auxilliary 'scope would need an erecting system, which is what increases the cost considerably.
Of course, the preceding babble is based on what limited knowledge I have. As there is nothing as authoritative as doing, I'll try this out and report back...
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Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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davidmcgo
sage
Reged: 10/09/04
Posts: 427
Loc: San Diego, CA
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Thanks Glen,
I forgot that Galilean's field is dependent on objective size and distance from eye. That would be much more limited by the exit pupil of the front binocular.
Dave
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holger_merlitz
sage
Reged: 02/08/04
Posts: 281
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I have finished a little write-up about the current Chinese version of the 2.3x40, which I recently received for testing. Here is the report:
http://www.holgermerlitz.de/opera2.3x40.html
Hope it might be of use to some of you.
Cheers,
Holger
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KennyJ
Reged: 04/27/03
Posts: 9960
Loc: Lancashire UK
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Thanks for yet another fine short review of a very interesting instrument , Holger .
Kind Regards
Kenny
--------------------
Two eyes and a preference to use both
Zeiss 7 x 42 BGAT
Captain's Helmsman 7 x 50
Nikon 10 x 42 Superior E
Swift Audubon Kestrel 10 x 50
Helios 15 x 70 Observation
Strathspey 20 x 90
Televue 76 APO
Zeiss 85 Diascope
Helios 102 f5 refractor
Various eyepieces barlows tripods mounts etc.
Panasonic Lumix DMC - TZ5 digital camera
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Wes James
Carpal Tunnel
Reged: 04/12/06
Posts: 2297
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Quote:
I've had a theory for several years now with regard to the optical illusion of objects not appearing as magnified as they truly are .
Kenny-
If you come up with very many more in-depth explainations that make such good sense on here, I fear they may rescind your "GRAND PRIZE for NON - INTELLECTUAL CONTRIBUTIONS" ! 
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Wes
Atlantic Beach, FL
Some bino’s from Miyauchi 5x32 Binon's up through Garrett 20x110 Signature's,
Some telescopes from a Stellarvue 80mm NHNG up through a couple of 8” reflectors…
And a wonderful 4.25" Delmarva Shiefspiegler!
Some good friends, made here on C/N.
Oh- several cats and a wonderful wife!
Anyone want a cat???? :-O
"When your work speaks for itself- Don't Interrupt" -Gamble Rogers
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KerryR
member
Reged: 12/05/07
Posts: 90
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I've got a pair coming... I'm pretty excited about these. Be curious to pit them against my 5x32w Binons, though that's apples to oranges, I suppose...
I think it could be fun to get the nebula filters for these, if/when they become available. I talked to Blue Planet, and he (I've forgotten the owners name) said he's still working on finding a machinist to do the mill work, so they're not available yet, nor does he know what the price is expected to be, nor the release date...
I suppose I'll have to try taping (or something) a 2" UHC filter on one side and a 2" O III (Probably too dark for this apeture) on the other,... I have 2 1.25" celestron UHC filters, which I might be able to affix to the eyepieces, but it sounds like there's not enough eye relief to make this possible. Maybe with the eye-cups removed?? Have to see when I get them. Anyone tried anything like this yet?
Thanks for the review, Holger
Kerry
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GlennLeDrew
sage
Reged: 06/18/08
Posts: 286
Loc: Ottawa, Ontario, Canada
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KerryR,
It's not the aperture that imposes a limitation to the use of narrow bandpass filters, but exit pupil. The Owl Eye has a rear eye lens clear aperture of >8mm, allowing you to use your eye's full pupil diameter. Therefore the really narrow filters are perfectly OK!
===================
I did some more in-depth examination with my Owl Eyes last night. As already noted, with the rear eyepiece cover threaded off, I can get my eyes sufficiently close to see the full field. For example, The full length of the Big Dipper fits in with no trouble, and Scorpius comes really close to squeezing in. Another nice view was provided by the "kite" figure of Bootes and Corona Borealis, again, in the field all at once.
Comparing the apparent field (which necessarily has a fuzzy edge, being a Galilean system) against a 5x21 having a 60 degree afov, I'd say it's pretty close. According to the numbers, 2.3X times 28 degrees = 64 degrees. And it might just be that large.
And as already pointed out, when the eye is centered properly, the stars are beautifully sharp out to a surprisingly large off-axis distance. I reaffirmed the important of centration of the eye, and indeed, it is folly trying to assess star sharpness well off-axis by looking away from the field center because of the now incorrect eye placement. When looking on-axis, the stars are sensibly sharp to the "edge" of the field.
I also verified that a Galilean design does NOT make a good auxilliary telescope to place behind another instrument's eyepiece. The portion of the field seen is VERY small!
--------------------
Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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KerryR
member
Reged: 12/05/07
Posts: 90
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Glenn,
When you removed the rear ep cover, were the lenses in any danger of falling out? I suppose I could just wait until mine arrive and check it out for myself...
I wonder if I could remove my 1.25" UHC filters from their mounts, remove the Owl Eyes eyepiece cover, insert the UHC filters (now reduced to glass disks), and replace the rear covers to hold the filters in place?
Maybe this is a little overboard... Just thought it might be cool...
Kerry
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GlennLeDrew
sage
Reged: 06/18/08
Posts: 286
Loc: Ottawa, Ontario, Canada
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When the rear pieces are removed, the outer barrel can fall off. But the eyepiece assembly itself stays in because it has a multi-start thread for focusing. The outer barrel has a small notch to align with a pin on the eyepiece barrel, which then allows for focusing. The gap under the outer barrel is small, and a tab of tape can be used to provide a good friction fit, and can be placed so that it's invisible.
In case I didn't stress it enough, daub some black paint on the exposed ground edges of the eye lenses. There are two surfaces requiring this:
1) Most importantly, the flat ring which immediately "frames" the ~8.5mm useable aperture, and
2) the conical section outside of this.
This will eliminate the vast majority of annoying scattered light.
There just ain't any room to insert filters behind the eye lens. Moreover, the filter would only force your eye farther back and hence reduce field, and it would be covered with eyelash marks in no time.
--------------------
Home-made 11X50 right angle bino, 8.1 deg. FOV
Modified 26X100 bino, 3.5 deg. FOV
Mediocre minds discuss people. Good minds discuss events. Great minds discuss ideas.
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KerryR
member
Reged: 12/05/07
Posts: 90
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I recieved mine Friday, and, miraculously, the sky was clear the same night, which is a big deal here in Michigan.
I was astounded at how sharp and clear the optics are, and how wide the field is-- Deneb to Albiero (just barely), and most of it usable. These kind of make my Myauchi 5x32w' obsolete, at least for this sort of wide field experience. The 2.3x40's are sharper accross more of the field (thought the 5x32's are sharper in the middle...)
I think these may be the 'funnest' astronomy purchase I've ever made. If ever there has | | |
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