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BX-2 Cascades 7x42 roof (1 Viewer)

jaymoynihan

jaymoynihan

Corvus brachyrhynchos watcher
Interested in any comments/mini reviews by folks that have used the 7x42 BX-2 Cascades Roof Prism, (Japanese made).

Thanks
 
They are lightweight. The one stop position only for the eye extenders. They do have a lot of ca but i ignore it once i use it for a while. At about 24 oz is lite. Is japan made it says on it. The focus on it is long but failry smooth. hinge is a bit loose on mine but stays in place. I like that is about 5.5 inch as i do not like anything longer than 5.5 inch. The view is good could be brighter but is so relaxing. So easy on the eye it just does something. I really enjoy the view is not up to par of birding binos but is of general purpose. It has a 3d view to it. It brings things to life. 7x and 6x power is rare these days as there are few models but i enjoy it a lot with no worry of image shake. I feel at home with this 7x binos.
 
Had a chance to look through one for awhile. Everything acceptable, with really good "eye comfort". Except; CA easily seen in the center of the FOV on branches against white sky, etc.
Strange, their BX-1 8x30 Yosemite has much better CA correction, for 1/3 the cost.
 
Jay,

The problem with the CA in the Leupolds probably has to do with their coatings.

Curiously, only 3 binoculars in the current Leupold binocular series are FMC. The Mojave BX-3 series; the Yosemite series and the Olympic series. All the rest are designated by Leupold on their web site as MC. http://www.leupold.com/observation/products/binoculars/

Click on the circles inside the objective lenses on specific binoculars.

Even Eagle Optics states that the Cascade BX-2 is multi coated.

If you are susceptible to CA this could explain why you saw more in the Cascade and less in the Yosemite.

Bob
 
Brock,
As I recall, Henry recently stated, if my memory is correct, that he didn't think ED glass made a difference in CA but he was not inclined to spend the time debating the issue anymore. As you know, I am not bothered by CA and I am inclined to agree with Henry. So I just threw that out for Jay as a possible explanation of why he saw more CA in the Cascades than in the Yosemites. There must be a reason why some people have so much trouble with CA and others don't.

And it is curious that Leupold has so many MC binoculars as opposed to FMC.

Anyway, I decided to get the 7 x 42 Cascade BX II at EO's sale price and I am surprised at how much I like it. Especially at that price! I'll have a report on it soon.

Bob
 
ceasar said:
Brock,
As I recall, Henry recently stated, if my memory is correct, that he didn't think ED glass made a difference in CA but he was not inclined to spend the time debating the issue anymore. As you know, I am not bothered by CA and I am inclined to agree with Henry. So I just threw that out for Jay as a possible explanation of why he saw more CA in the Cascades than in the Yosemites. There must be a reason why some people have so much trouble with CA and others don't.

And it is curious that Leupold has so many MC binoculars as opposed to FMC.

Anyway, I decided to get the 7 x 42 Cascade BX II at EO's sale price and I am surprised at how much I like it. Especially at that price! I'll have a report on it soon.

Bob
Click to expand...

Bob,

Henry would nix the idea that coatings had anything to do with seeing more CA. After he shot down the lead free glass hypothesis (HG→HGL), I suggested that the increase in CA might be due to the warmer bias of the HGL's coatings (more red, more red fringing), but he nixed that too.

He did speculate that the focusing elements in roofs, which was something added in the mid to late 1990s, might be a contributing factor to the increase in reports of CA in roofs at that time. And then there was the distinction btwn negative and positive focusing elements, but I don't remember which was the offending party.

I've concluded that the most important reason people see CA or more CA in the same bins that others don't see CA or see it negligibly has to do with one's eyes and perception rather than glass or coatings.

I'll throw another theory out there for Henry to chew on (or eschew :). In general, it seems that older users see more CA than younger users. This could be due to incipient cataract formation. From my experience, contracts take years to form before they get to the point where your eye doctor is even going to mention it. But even before that point, they could be causing a higher chromatic dispersion.

Like "rolling ball," pincushion, field curvature, and image blackouts, reports of CA vary from person to person. However, when you have numerous reports of CA in a certain bin or series of bins, then I think there's more going on than eyeball/brain sample variation, and there's some flaw in the optics, air spaced vs. cemented lenses, or shorter FL, etc. causing the problem.

No doubt the Zeiss FL controls CA better than the Leica HD, too many reports to be all user dependent differences. Same with the many reports of "higher than average" CA with the HG/HGLs. Even if you don't see it in your 10x32 HGLs, there are too many who see CA in HGLs to write it off as user dependent differences.

As far as ED glass controlling CA, well, that's what it's made for! I don't know if Henry disputed that, but if so, I can produce scientific evidence to show otherwise. Edz has disputed its effectiveness in controlling CA in 8x-10x bins, but he uses his bins primarily for stargazing where CA is less of an issue than birding, and like you, he seems to be immune to CA.

What I would concede, is that not all ED glass is created equal, some have lower dispersion than others. However, except for Minox, no other manufacturer to my knowledge specifies the type of ED glass they use, so there's no way to verify this.

Brock
 
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Having tried and sent back the 7x42 cascades, here is my take on the CA. Nothing exotic, just the normal reason; the tolerances speced for the lense elements not providing enough correction of that abberation.
CA has to do with the failure of the different wavelengths of light to focus at practically speaking, the "same point". It is simply sloppy manufacture or sloppy design of the product.
 
jaymoynihan said:
Having tried and sent back the 7x42 cascades, here is my take on the CA. Nothing exotic, just the normal reason; the tolerances speced for the lense elements not providing enough correction of that abberation.
CA has to do with the failure of the different wavelengths of light to focus at practically speaking, the "same point". It is simply sloppy manufacture or sloppy design of the product.
Click to expand...

IOW, cheap Chinese crap. :) Too bad, 7x shouldn't be too hard to correct for CA, so the QC or design must be poor.

The HGL/Premier is manufactured in Japan, and it's not cheap and is presumably manufactured with high quality materials, so I'm still puzzled by why it has higher than average CA and even more puzzled why Nikon has not addressed this issue.

Perhaps after Meopta comes out with its HD line at the same price point, Nikon might be forced to move the HGL into the 21st century or get left behind.

Brock
 
The Leupold BX II 7 x 42 that I have is almost certainly made by the same Japanese Company that makes Swift's Model #828 8.5 x 44 which I own. The similarities in their construction are so obvious that it could not be otherwise. The size of their eye cups and their operation are the identical. The construction and appearance of their oculars are identical. Their focus wheels with the attached diopter adjustment are identical and work exactly the same. The raised stamping "Made In Japan" is in the same place although the size of the letters is slightly different and the Blind Cap for the Tripod Mount is the same except for the logo. The exterior appearance, of course is different, but that is cosmetic. The Swift's covering feels slightly harder and more substantial in the hand; the Leupold is more rubbery.

The Swift is stated to be "Fully Multi Coated" and the Leupold to be "Multi Coated." When compared, the differences in the coatings are evident.

Swift: http://www.eagleoptics.com/binoculars/swift/swift-audubon-8-5x44-roof-prism-binocular

Leupold: http://www.eagleoptics.com/binoculars/leupold/leupold-bx-2-cascades-8x42-binocular

The price differential seems to be based on the differences in coatings and the exterior construction. I would think that they both underwent a similar QC check.

When I registered my Swift I called the company and spoke to the manager. He told me that in the 4 years he had worked there that they had trouble keeping the 828 in stock and that they were practically never returned for problems.

Bob
 
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ceasar said:
The Leupold BX II 7 x 42 that I have is almost certainly made by the same Japanese Company that makes Swift's Model #828 8.5 x 44 which I own. The similarities in their construction are so obvious that it could not be otherwise. The size of their eye cups and their operation are the identical. The construction and appearance of their oculars are identical. Their focus wheels with the attached diopter adjustment are identical and work exactly the same. The raised stamping "Made In Japan" is in the same place although the size of the letters is slightly different and the Blind Cap for the Tripod Mount is the same except for the logo. The exterior appearance, of course is different, but that is cosmetic. The Swift's covering feels slightly harder and more substantial in the hand; the Leupold is more rubbery.

The Swift is stated to be "Fully Multi Coated" and the Leupold to be "Multi Coated." When compared, the differences in the coatings are evident.

Swift: http://www.eagleoptics.com/binoculars/swift/swift-audubon-8-5x44-roof-prism-binocular

Leupold: http://www.eagleoptics.com/binoculars/leupold/leupold-bx-2-cascades-8x42-binocular

The price differential seems to be based on the differences in coatings and the exterior construction. I would think that they both underwent a similar QC check.

When I registered my Swift I called the company and spoke to the manager. He told me that in the 4 years he had worked there that they had trouble keeping the 828 in stock and that they were practically never returned for problems.

Bob
Click to expand...

Bob,

You should have asked him why in this day and age when the Chinese are manufacturing dielectric prisms with 99% reflectivity, the 828's overall light transmission is only 75%!

If allbinos is correct, that reflects poorly on the Swift 828, literally.

"The transmission was the thing that disappointed me the most. A weak result in this category was obvious as soon as I looked through the binoculars – you could immediately notice this device gave the darkest image of all group of binoculars, tested at the same time."

http://www.allbinos.com/167-binoculars_review-Swift_Optics_828_HHS_Audubon_8.5x44.html

Brock
 
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