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EdZ
Professor EdZ


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William Optics 7x50 ED binocular minireview
      #694293 - 11/19/05 12:55 PM

Ive have a William Optics 7x50 ED for testing and Ive had it out just a little so far. So I can report some early findings.

This is a heavy binocular about 3.5 pounds, but not much different than the two other 7x50s I have in the house, both over 3#. I found it still pretty stable to hand hold.

The IPD range is 57.5 to 72mm.

The coatings are particularly impressive. I had to try very hard to see my reflection at all in the light bouncing off the objective lens. I compared to several other binoculars and this William Optic 7x50 ED shows so very little reflection it is comparable to the Nikon Superior E 12x50 and maybe even slightly better than the Fujinon FMT-SX 16x70.

This is an Individual Focus eyepiece binocular. For my eyeglass corrected eyes the diopter settings are near exact on zero from my evening of viewing stars at infinity. For my resolution readings at a distance of 125, I found my eyeglass corrected diopter settings show a reading of +1. The diopter range extends from +6 to 6 and eyepiece travel is about 4.5mm in or out from the zero setting.

The aperture measures 50mm with no apparent stops.

There are no apparent edges of exit pupil cut off. They are nice and round.

I measured exit pupil several times and come up with about 7.2mm. That is within 1% of expected and could be measuring error.

Close Focus was measured at 23 feet, not the 4m as published.

Objective covers are captive. Rather than over caps, they are the stick in type. They are a poor fit and repeatedly came open of their own accord. I found them particularly annoying.

Eye guards are rubber fold down and when fully extended are a nice soft rubber that you can push up against your eye sockets.

The binocular L-bracket mounting hole is set back several mm behind a very narrow space in the prism housings. I have 8 different styles of binocular brackets. Only two would work, one was custom made and it is very non-standard and the other is the Orion Small L bracket. None of my deluxe binocular L brakets would work. Either you need a bracket with a 5mm extension nub at the binocular mount screw or you need a bracket that is only 7-8mm wide. None that I know of are that narrow. The narrow style Pentax L bracket is about 20mm wide and would only allow me to get the IPD in as close as 68mm.

Eye relief is very long. Exit pupil focus distance is 18mm behind the eyecups when they are folded down for use with glasses. Depth to the lens is 7.4mm. Pressing my eyeglasses hard up to the folded down eyecups would result in minor blackout. With the eyecups folded down for eyeglass viewing, handheld I needed to place my thumbs against my cheekbones to hold the binocular far enough out to prevent blackouts. That is similar to the Nikon 12x50 SE. This actually should bode well for those with thicker glasses, as I find I usually need only about 14mm with my thin glasses. I could almost see the entire fov while wearing my glasses even with the eyecups fully extended.

Resolution as tested with a USAF line pairs chart shows 13.5 arcseconds in subdued light and 12.1 arcsec in bright light. These results produce apparent resolution of 95 arcsec subdued and 85 arcsec in bright light. These readings are in line with almost every other binocular Ive tested, as most other binoculars Ive tested fall between 97 and 90 in bright light. While I have suspected seeing 85 arcsec apparent resolution with several other binoculars, with this binocular, I suspected seeing 76 arcsec apparent. I made no attempt to use supplemental magnification behind the lens.

Handheld, I found I was able to easily read 10mm tall x 2mm thick lettering at 125 feet. Thats less than 1 arcminute resolution or approx 6 arcminutes apparent resolution handheld.

The fov is stated as 7 30, or 7.5. I measured the True field of view as 7.3 to 7.4, very close to stated. That gives an eyepiece with an Afov of 52. There was no feeling of a narrow Afov with these binoculars. In fact I was surprised at the nice wide field of view. The impression one gets handheld is a field of view sharp completely across the view.

Accurate measuring of sharpness of image across the field of view showed some problems. The sharpness is not balanced. 16 Cygni, a 6.0-6.1/39 double star could be seen clearly separated out to 90% of the field on the right side. However on the left side of the view, it became distorted beyond perception at 70% out from center. Both barrels produced the same error. The same error was noticed when observing the USAF resolution bar charts.

The right barrel shows some minor amount of astigmatism. This was seen on-axis as a bright star was defocused inside and outside of focus. The orientation of the out-of-focus image would flip 90 as I passed thru the precise focus point.

The binocular is stated as waterproof / shockproof. I can say that it seems very ruggedly built. I did not attempt a water immersion test. I appreciate waterproof binoculars since I often leave my equipment out overnight. Quite often, I find my equipment completely soaked with morning dew. I never get too concerned about my waterproof equipment, but always need to protect binoculars such as the Nikon SE.

This binocular uses some combination of ED glass. Chromatic Aberration is very well suppressed. I could not produce any false color on any astronomical objects anywhere in the field of view, including mag1 stars, mag 1.7 Mars and the near full moon. Also I could not produce any false color in daylight when viewing the edges of white porch posts in sunlight or when viewing sunlit tree limbs against a bright blue sky background.

Internal baffling is flat gray/black ridges in the barrels. I could not produce any ghosting or internal reflections with the moon off axis or just out of the edge of the field of view.

The binocular is complete wrapped in a 1.2mm thick rubber coated armor. The rubber armor is brown.

Collimation of star points was not seen to be in error by more than a very small amount, well within standards and easily merged. Collimation of the field overlap is off by several arcminutes. It is more noticeable in daylight viewing, where I would say field overlap is off by 10 to 12 inches at 200 feet. That represents about 15 arcminutes, or 3% of the field. There are no externally accessible prism adjustment screws found under the rubber armor.

The IPD hinge is solidly stiff and very smooth. The eyepieces likewise are solidly stiff, but move with a quiet smoothness. Nothing moves unless you intend to move it.

Night-sky observing impressions show a very clear bright view. At 7x, not much detail can be seen, but that impression is from one who spends a lot of time behind 16x70, 20x80, 25x100 and even 30x-40x100 binoculars. So I cant very well compare this 7x binocular to some of the star counts Ive done or to the density seen in clusters like the double cluster at 20x or 25x. I did find one particular object of interest last night. The moon was just rising and very low behind some thin clouds, so it didnt much interfere. I scanned around (mounted) in the vicinity of M31 and had some pleasant views. I dropped down a little lower to search for M33 a much more difficult to see extended galaxy. At first I didnt see it. Once I got out my charts and located the exact spot, I was then only able to see it with averted vision. As I would wiggle the binocular back and forth just a little, maybe a degree, I could see the diffuse background glow of this very extended face on galaxy. I was then able to confirm what I saw by moving away and coming back to the area. Using the same back and forth scan, I could pretty easily pick out M33 as just ever so slightly brighter against the background sky. I would consider this an indicator of good contrast.

This is a very nice binocular. Some users are content with low power views. It would not be my binocular of choice for astronomy, but it could be for any number of people who cherish those low powers wide swaths of sky. This particular binocular could provide you those views. It seems pretty comfortable to hand hold and produces no false color or internal reflections to speak of. If you have the large eye pupils to take advantage of this 7.2mm exit pupil, you would have a very bright image. This large exit pupil will also make it easy for you to hold onto the view in daylight, although your effective aperture would be much smaller. Still, the image seems crisp and daylight color rendition seems pretty natural.

The binocular sells for $299.00 from William Optics.

edz

--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
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KennyJ
The British Flash


Reged: 04/27/03
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Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #694436 - 11/19/05 02:16 PM

For a MINI - REVIEW based on " early findings " this was a surprisingly highly informative piece . Well done again Ed .

I also get a strong initial impression , as I do with the Captain's Helmsman 7 x 50 IF , that for less than $300 , anyone given to lower - magnification , hand - held binocular viewing , particularly in darker sky locations , could do far worse than treat themselves to one of these .

Others have commented elsewhere that the use of ED glass for binoculars as low powered as 7x is either a waste or a " gimmick " , but some of Ed's observations about lack of CA , appear to contradict that opinion .

The CN binocular mini - review section will be all the richer for the inclusion of this .

Kenny

--------------------


Milton Wilcox R.I.P






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ngc6475
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Re: William Optics 7x50 ED binocular minireview new [Re: KennyJ]
      #694476 - 11/19/05 02:39 PM

Kenny's right; those are some impressive "early findings". Later results will be more impressive yet! I wish William Optics was releasing a 10x50 version of these glasses at this price, as it would be a more interesting binocular for astronomical purposes. WO has an APO roof prism binocular in the 10x range which lacks p-coatings, but still looks promising. I emailed them to find out if they intended to release this bino with phase coatings anytime soon, but I have received no definite answer at this time. Still, this company is offering a wide range of intriguing products, and it will be worth keeping an eye on their web site for futher developments! It will also be interesting to see how Ed fares with the 7x50 binocular, too!

--------------------
Walter

"There are nights when the wolves are silent and only the moon howls."
-George Carlin



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Mark9473
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Re: William Optics 7x50 ED binocular minireview new [Re: ngc6475]
      #694643 - 11/19/05 04:16 PM

"shockproof" is a very strong statement, isn't it?
I can just see my 15-month old son pounding away with them...

Is there a sort of standard method to allow this statement from a certain mechanical performance onward, and what does it mean in practice that these binoculars can take? Dropping? Onto what?

--------------------
Mark
Leica 8x20; Nikon 7x35; Vixen 8x42; Orion 15x63; Docter 15x60
WO Megrez II 80 FD / APM 107mm f/6.5 / Mewlon 210 on DM-6 + Berlebach Planet


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Arek
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Re: William Optics 7x50 ED binocular minireview new [Re: Mark9473]
      #694723 - 11/19/05 04:57 PM

Great review! It seems to nice bino for resonable prize.
Looks simillar to Fujinons FMTR-SX.

Ed, did you check all air-to-glass surfaces for presence of antireflection coatings?

In my opinion the binoculars will soon evolve by two ways.
There will be growing number of binos with low dispersion glass both in objective and eyepieces. WO 7x50 ED and Vixen
Ultimas ED are good examples. The second way will be the return of era of wide field binos, but this time with sharp FOV with Miyauchi 7x50 Binon as first member of this group.
What do you think?

Greetings!
Arek

--------------------
Megrez I 80/480, Minolta Activa 10x50


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holger_merlitz
sage


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Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #695055 - 11/19/05 08:48 PM

Thanks, Ed, for the detailed report! I just want to add the original Chinese source of this binocular:

http://www.united-optics.com/products/milit-s/milit-s-1/milit-s-1.htm

They mention a 10x50 and 15x70 version being in preparation, too.

Best,
Holger


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EdZ
Professor EdZ


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Re: William Optics 7x50 ED binocular minireview new [Re: holger_merlitz]
      #695110 - 11/19/05 09:28 PM

If this binocular were made available in 10x50, and met the same criteria I see in this sample, I would think it would vie for position as one of the best 10x50s on the market.

I did not dismantle the binocular to inspect all glass surfaces, and i'm sure I won't. Also, I'm not sure I would trust colors of reflections in the objective lens or the outer eye lens to give me an indication of what kind of (or if any) coating is on any other surface.

Thanks for the comments.

Tonight I observed a 22" double cleanly split for an apparent separation of 154 arcseconds. Actually, I expected this, and it's in line with other binoculars. I'm curious to see the transmision (LM on M45 chart). But my eyes have been in front of this screen for hours, so maybe another time.

This afternoon I pulled out several other binoculars to test CA. I was impressed that the WO ED did not show any edge CA when looking at tree branches against sky background. So I wanted to check on the same branches while still under bright skylight how several others performed.

Oberwerk 8x56 shows purple band one side, green on the other.
Captain's Storm King Mark II 7x50 (older version Swift origin) shows a thin yellow/green band at edge.
Fujinon FMT-SX 10x70 shows yellow green band at edge.

edz

--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
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DJB
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Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #695477 - 11/20/05 05:52 AM

Hi Ed,

Nice review. I think you found a keeper, and I KNOW Kenny has.

A point you made struck my fancy. Even tho the 7.5* FOV is not all that large, whenever the view is excellent, as you have so stated, it does not exhibit that bloody tunnel effect and all the rest of what we address here.

I think that you have expressed, in words, what I have experenced with my FUJI FMT-SX 7x50s, which are also 7.5*, stated. It is difficult to describe that experience, but I believe that you have come pretty d___ close. Thanks.

Regards,

Dave.


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EdZ
Professor EdZ


Reged: 02/15/02
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Re: William Optics 7x50 ED binocular minireview new [Re: DJB]
      #695492 - 11/20/05 06:18 AM

Again I tested CA last night and this morning. None of the stars or the planets, Mars, Saturn or Jupietr is bright enough to cause any CA. So, once again I turned to the moon. I also had my Fujinon FMT-SX 16x70 out with me so first I checked those. With the moon at the right edge of the field, I could easily see a blue band on the full sunlit edge of the moon (towards the center of the binocular). With the moon near the left side of the view, I could easily see a broad yellow band on the full sunlit edge of the moon towards the outer edge of the field of view. No false color is seen on the terminator edge of the moon.

In the WO ED 7x50, with the moon at the right side of my fov, if I tilt my head and look right at it I could not see any band of color. If I kept both my eyes right up against the eyepieces and scanned right by moving just my eyes, I could see a partial blue band sometimes appear. It did not span the entire sunlit edge of the moon, maybe only 1/3 of the edge.

(edit) I was able to produce a thin yellow band when doing the same thing with my eyes to observe the moon at the left edge of my view. Once again, the band did not span the full extent of the sunlit edge of the moon. It seemed to be only about 1/4 to 1/3 the length. It would quickly disappear as I moved my eyes around.

(added)I aslo checked my Garrett Optical 20x80 triplet. With the moon at the right edge of the field, there was a yellow or red band on the full sunlit edge of the moon (towards the center of the binocular). With the moon near the left side of the view, I could easily see a thin green band on the full sunlit edge of the moon towards the outer edge of the field of view. On-axis I could see alternately a blue band or yellow band, depending on how my eyes were positioned at the moment. No false color is seen on the terminator edge of the moon.

So, with some work, I was just barely able to produce a little false color in the WO 7x50 ED. It would not stay there. When I tilted my head even slightly to look right at the moon in the outer edge of the field, the slight blue would quikly disappear.

edz

--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21

Edited by EdZ (11/21/05 06:00 AM)


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brocknroller
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Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #695753 - 11/20/05 11:28 AM

Arek,

I have an Eagle Optics 10x50 ED Voyager binocular. It looks identical to the new Vixen 10x50 Geoma, same armoring and shape. To the best of my knowledge it is the only 10x50 ED model ever made.

Vixen and Celestron both offered a 9.5X44 ED, and Vixen made a 10x44 Ultima ED, but according to a recent email I received from Vixen-Japan, both ED models have now been discontined. If you've heard differently, please post.

"By Celestron" is printed on the prism housing of the EO ED Voyager; however, I suspect it was actually made by Vixen.

CA is just barely visible at the lateral edges of the moon, but I have to really look for it. Surprisingly, I see the least CA slightly off-axis rather than directly on-axis.

Brightly colored stars are quite vibrant, and night sky contrast is better than other 10x50s I've had (Ultima, Nikon Lookout, Olympus EXP 1, Orion Ultraview, Swift Sea Wolf).

Birds against extreme contrast backgrounds also show little or no CA.

Using a RAF chart, the ED matched the Nikon 10x42 SE in resolution. But what sets this binocular apart from the SE and other non-ED bins is its greater color saturation.

With the Nikon SE, I can see remarkable detail, however, the SE reveals only a few subtle COLOR variations in a male Cardinal's bird feathers (which other than the wings appears solid red at first glance). The 10x50 ED shows a wide range of color variation and some subtle colored details not visible with the SE.

Yesterday, I spotted two cedar waxwing families, who have taken up winter residence in my backyard "wildlife habitat" . I watched them for about a half hour with my 8x32 SE, Swift 8.5X44 Audubon, and 10x50 ED. All three bins are very close in resolution, despite their different powers and objective sizes. The colors looked somewhat "flat" in the first two bins (more contrast with the SE) whereas the red wing tips and yellow-tipped tail feathers popped out with the ED binoculars and showed subtle variations in color.

Given that COLOR variation is a key field mark identifier for birdwatchers, particularly when trying to discern different species in the same genus, I'm surprised there are so few ED binoculars made.

Cost is obviously NOT the reason since Celestron and Eagle Optics priced their ED bins between $300 and $400, and now WO has a ED bin for under $300.

--------------------
Press: Are you a mod or a rocker?
Ringo: I'm a mocker


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Arek
member


Reged: 11/16/05
Posts: 53
Loc: Warsaw, Poland
Re: William Optics 7x50 ED binocular minireview new [Re: brocknroller]
      #695920 - 11/20/05 02:01 PM

Yesterday I received a new catalog of Vixen binos and field scopes and both ED Ultimas are present there. I hope they will sell them still.

From Polish distributor of Swarovski I know that during last
press conference and meeting of the distributors people were taking about some revolutionary binos of Swarovski which will appear on autumn 2006. Taking into account that CA is clearly visible in all Swarovski binos I saw, I think they may try to use fluorite or other low dispersion glass to minimalize aberrations. I hope they will.

Arek

--------------------
Megrez I 80/480, Minolta Activa 10x50


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mooreorless
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Re: William Optics 7x50 ED binocular minireview new [Re: brocknroller]
      #695961 - 11/20/05 02:36 PM

Quote:

Arek,

I have an Eagle Optics 10x50 ED Voyager binocular. It looks identical to the new Vixen 10x50 Geoma, same armoring and shape. To the best of my knowledge it is the only 10x50 ED model ever made.

Vixen and Celestron both offered a 9.5X44 ED, and Vixen made a 10x44 Ultima ED, but according to a recent email I received from Vixen-Japan, both ED models have now been discontined. If you've heard differently, please post.

"By Celestron" is printed on the prism housing of the EO ED Voyager; however, I suspect it was actually made by Vixen.

CA is just barely visible at the lateral edges of the moon, but I have to really look for it. Surprisingly, I see the least CA slightly off-axis rather than directly on-axis.

Brightly colored stars are quite vibrant, and night sky contrast is better than other 10x50s I've had (Ultima, Nikon Lookout, Olympus EXP 1, Orion Ultraview, Swift Sea Wolf).

Birds against extreme contrast backgrounds also show little or no CA.

Using a RAF chart, the ED matched the Nikon 10x42 SE in resolution. But what sets this binocular apart from the SE and other non-ED bins is its greater color saturation.

With the Nikon SE, I can see remarkable detail, however, the SE reveals only a few subtle COLOR variations in a male Cardinal's bird feathers (which other than the wings appears solid red at first glance). The 10x50 ED shows a wide range of color variation and some subtle colored details not visible with the SE.

Yesterday, I spotted two cedar waxwing families, who have taken up winter residence in my backyard "wildlife habitat" . I watched them for about a half hour with my 8x32 SE, Swift 8.5X44 Audubon, and 10x50 ED. All three bins are very close in resolution, despite their different powers and objective sizes. The colors looked somewhat "flat" in the first two bins (more contrast with the SE) whereas the red wing tips and yellow-tipped tail feathers popped out with the ED binoculars and showed subtle variations in color.

Given that COLOR variation is a key field mark identifier for birdwatchers, particularly when trying to discern different species in the same genus, I'm surprised there are so few ED binoculars made.

Cost is obviously NOT the reason since Celestron and Eagle Optics priced their ED bins between $300 and $400, and now WO has a ED bin for under $300.




I agree with Brock about the Eagle Optics 10x50 ED showing more color saturation than all the Nikon SE's,that would be 8,10 and 12 SE.We were using the Edmund's USAF Resolving Power Chart and this chart has red,green,yellow,blue and black USAF targets in a x shape.I really was kind of surprised to say the least and WOULD NOT BELIEVE IT IF I DIDN'T SEE IT WITH MY OWN EYES.
Steve M

--------------------
Regards,Steve M



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GLR GROUP
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Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #696104 - 11/20/05 04:21 PM Attachment (263 downloads)

Hi Edz.
I am happy to reading yours report. My impressions are similar to yours and I am happy for this. :-)A new Italian company has sended to me this binocular, (please see the photo) , that it is equal to the W.0.7x50. I am testing it in these days, vs other binoculars. The curvature of the field is present, observing Vega, after the 70% of the field, while, with less luminous stars, I perceives it after the 80% of the field. The Swaroski SLC 8x56 that I have in test introduces the same distortion and moreover is present the chromatic abberration ( of Vega) after the 40% of the field, but the star showed in the swarosky are more pinpoint. (about +15%) I am sorry for my poor english...
Pier

Attachment

--------------------
[url] www.binomania.it [/url] you can find many binoculars reviews!
[url] www.landscapephotography.it [/url] a tribute to italian and switzerland landscapes


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EdZ
Professor EdZ


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Re: William Optics 7x50 ED binocular minireview new [Re: GLR GROUP]
      #696242 - 11/20/05 06:33 PM

Hi Pier,

your English is fine, no need to apologize anymore. We know you now.

Early tonight I re-checked the sharpness across the field. I mounted the binocular on a slo-motion head and observed nu Draco, taking notes.

Nu Draco is 62 arcseconds. That gives 434 arcsec apparent resolution.
visible out to 95%/100% to the right, towards the 3 o'clock position.
visible to 90% towards top, distorted further out.
visible to 80-85% towards bottom, distorted further out.
visible only to 70-75% towards left, distorted further out.
Stars begin to spread out like arcs.

This would indicate the sharpest point in the field is shifted about 1 off-center approximately towards the 2 oclock position.

There is no major difference in the field overlap when focused at infinity. This was noticed yesterday in daylight when focused at 200 feet. This must be seen in daylight as parallax when observing close objects. On stars, with nu Draco at the edge, I measured overlap within 2 arcminutes. That's negligible. In daylight I measured 1 foot in 200 feet or 15 arcminutes, a very noticable field error.

Stars are merged to within less than 1 arcmin.

edz

--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
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KennyJ
The British Flash


Reged: 04/27/03
Posts: 20139
Loc: Lancashire UK
Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #696260 - 11/20/05 06:50 PM

Ed ,

Thanks for the " sharpness " update .

To roughly translate these findings to " layman's terms " this is far from the first example we've heard of , whereby the " sweet spot " is off - centre to one direction or other .

It may prove tuitional to some readers ( including myself ) , for someone to explain , in " layman's terms " what would , or could , bring about this phenomenum .

Kenny

--------------------


Milton Wilcox R.I.P






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EdZ
Professor EdZ


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Re: William Optics 7x50 ED binocular minireview new [Re: KennyJ]
      #696267 - 11/20/05 06:54 PM

Hi Kenny,

This is maybe the 4th or 5th binocular now that I have seen this. It is not the worst, but to me it is very noticable. In my opinion, it should not be present at all. I have many fine binoculars that don't show this off-center anomoly. I am as curious as you as to why this might occur!

edz

--------------------
Teach a kid something today. The feeling you'll get is one of life's greatest rewards.
member#21


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brocknroller
Carpal Tunnel


Reged: 10/16/03
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Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #696439 - 11/20/05 09:22 PM

PIER: Are those figures you gave for edge sharpness averages (median)? Or did you check the edges in all directions as Edz did? I'm wondering if he has a "bad" sample or if this "edge shift" is visible in all WO 7x50 ED binoculars.

AREK: Not sure why the Vixen rep told me the EDs were discontinued if they are still showing them in their latest catalog! The reply was in perfect English, so I don't think he misunderstood me, and he pointed out that the Vixen Geomas were the same as the Ultimas, but with rubber armoring.

I searched the Internet for the 9.5X and 10x44 Vixen ED bins, but only found one camera store (Holga.net). I wrote the company, and they said they were no longer available, and today I see both EDs have been removed from their Website. If you find a store that still carries the Vixen ED bins, please send me a private message. Thanks.

Also, Swift used to make a 8x44 ED Ultralite, but that has been discontinued. The frame looks like an Ultima. I suspect the 44mm ED objectives are the same ones used in the Audubon ED, Vixen, and Celestron ED bins.

--------------------
Press: Are you a mod or a rocker?
Ringo: I'm a mocker


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Rick
Post Laureate


Reged: 04/12/05
Posts: 3285
Loc: Tokyo, Japan
Re: William Optics 7x50 ED binocular minireview new [Re: brocknroller]
      #696476 - 11/20/05 09:47 PM

Quote:

If you find a store that still carries the Vixen ED bins, please send me a private message.




How about 22x80 ED's? https://www2.vixen.co.jp/marketingshop//webshop/original/bed22x80.jsp

cheers,
Rick


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holger_merlitz
sage


Reged: 02/08/04
Posts: 284
Re: William Optics 7x50 ED binocular minireview new [Re: EdZ]
      #696512 - 11/20/05 10:15 PM

Quote:

Hi Kenny,

This is maybe the 4th or 5th binocular now that I have seen this. It is not the worst, but to me it is very noticable. In my opinion, it should not be present at all. I have many fine binoculars that don't show this off-center anomoly. I am as curious as you as to why this might occur!

edz




This type of problem could be the result of an incomplete collimation process during end-control. They are checking whether both optical paths are parallel. If one of the prisms is mounted incorrectly, so that a small tilt remains, then, during collimation, they are tilting the second prism in exactly the same manner. Both optical paths are parallel now, but the images are slightly out of center. At high magnifications some coma might show up then (perhaps visible with a booster?), but at 7x these effects may remain invisible.

Maybe, Bill Cook knows more about what could be going wrong here.

Best,
Holger


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brocknroller
Carpal Tunnel


Reged: 10/16/03
Posts: 1983
Loc: Bedford Falls, Pa.
Re: William Optics 7x50 ED binocular minireview new [Re: Rick]
      #696703 - 11/21/05 01:03 AM

Quote:

Quote:

If you find a store that still carries the Vixen ED bins, please send me a private message.




How about 22x80 ED's? https://www2.vixen.co.jp/marketingshop//webshop/original/bed22x80.jsp

cheers,
Rick




Thanks, Rick. Wait a minute, 98,000 yen!!! Oh, that's 821.79 USD.

I'm actually interested in a smaller aperture, close focusing ED binocular for birding, though this "species" seems about as rare these days as an Ivory-billed Woodpecker.

I bought a 9.5x44 ED a few years ago (paid more than I should, considering it was out of collimation and the optics had seen better days). Also saw one on eBay a few months ago that looked like it was run over by a herd of elephants.

I never compared the 50 and 44mm EO Voyagers side by side, but I corresponded with someone who did. He thought the optics on my 10x50s were sharper, but he preferred his 9.5X's feel (shorter) and closer focus. (btw, the EO 9.5X44 Voyager is identical to the 9.5X44 Celestron ED except it's black and has the EO logo on it).

From what he said in his comparison and my own experience with the Celestron 9.5X44 ED, I don't think the views would be THAT much different at 24 ft., despite the extra degree FOV. The 50s really excel at dusk and at night when they eek out details (on owls, for instance) I've never seen through any 50mm or under binocular.

However, it appears that optics companies have decided that ED glass belongs only in their spotting scopes, small refractors, and now big binoculars.

The WO 7x50 has IF EPs, so they are not ideal for birding, though they may work for feeder birding, given the closer than advertised close focus. The other exception is Minox, though the smallest ED bin they make is the Minox 10x58 ED BR. Besides the exorbitant price and hefty weight (52 ouches!), I find most roofs hard to hold steady with my LARGE hands.

Given the limited number of ED birding bins that were produced worldwide (mostly to rave reviews) and the conventional "wisdom" that ED glass is wasted on lower powers/small apertures, my guess is that most birding binocular designers would never suggest the design to their companies.

The Swift 8.5X44 820 ED stands ALONE as the ONLY ED birding binocular currently in production (unless the Vixen EDs in Arek's catalog surface somewhere on the planet).

Unfortunately, the Swift Audubon 820s oversized, hard, sharp-edged eyecups didn't fit my face, and I couldn't see the entire FOV even with the eyecups down. The short ER was also unpleasant. The bulky build fit my large hands well, but I can see how these binoculars could be too large for birders with small or even average-sized hands.

If I were Rod Stewart or some other wealthy celebrity with truckloads (lorry loads) of money, I would commission an optical designer to make a custom ED binocular for me.

It would have: the ergonomics of the Nikon 10x42 SE; the EPs of a 5-element Swift 8,5X44 804 Audubon (modified with an added field flattener to boost edge performance but with enough pincushion to give "natural" 3-D views); the soft rubber, twist-up eyecups of the 10x42 Premier LX; Fuji EBC FMC, and 44mm ED objectives. Add WP/FPing, and cut the CF down to 12 ft. but keep the DOF very good.

Not sure what to do after I achieved birding binocular NIRVANA except to commission a 8x32 SE ED!

Ah...
Some guys have all the luck,
Some guys have all the pain,
Some guys get all the breaks,
Some guys did nothing but complain....

--------------------
Press: Are you a mod or a rocker?
Ringo: I'm a mocker


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