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Old Friday 8th January 2016, 15:36   #1
FrankD
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Opticron DBA VHD 8x42 Review

Do you know how much I love doing optics reviews? I really do. They are so much fun and now is a great time to be involved with the sport optics industry because there are so many new and interesting products. If it isn’t the startup companies with their new designs then it is the longstanding, respected companies producing a new model or two each year. It is a product from the latter type of company that I will be commenting on in this review.

Opticron is a company based out of Great Britain. They have been in business for well over 40 years but have only been in the US market for a little over four. Their binocular line hits just about every price point from around $100 all the way up to just over $800. I have been given the opportunity to review their new flagship binocular, the DBA VHD 8x42. The MSRP for this model is listed at $915 but I see the street price puts it just under $800. I have had this unit for a couple of months now so I have really had an opportunity to use it extensively. So, without further adieu let us get to it…..

Advertised features and specs via the Opticron USA homepage…..

http://www.opticronusa.com/Pages/dba_vhd.html

• Compact, lightweight roof prism design
• Dual hinge, single axis body
• Textured rubber armoring
• Nitrogen gas filled waterproof (16ft depth)
• VHD optical system incorporating a high quality ED glass objective system, phase corrected prisms with Oasis prism coating S-type multi-coating to all air/glass surfaces
• Flat field vision
• Long eyerelief for spectacle wearers
• Multi-stage twist type retractable eyecups
• 500° turn smooth action wide wheel focusing
• Close focus to 8.2ft
• Central diopter adjuster
• Tripod adapter socket

Field ft/1000yd 367
Field m/1000m 122
Close Focus ft / m 8.2/2.5
Eyerelief mm 22
IPD mm 56-74
HxW inches 5.7x5.0
HxW mm 145x126
Weight oz / g 24.6/696
MSRP $ 915.00


Lets mix it up a bit and talk about Ergonomics and Mechanics first…..

Ergonomics/Mechanics:

The VHD is an open bridge design but it is a relatively short open bridge design compared with many of the open bridge/ED glass binoculars on the market. As you can see from the specs list it measures at 5.7 inches long. I am able to fit both my ring and middle finger in between the two bridges. Most of the binocular is rubber-armored except for a small strip between the bridges. This gives the feel of a bit of an indent for your fingers to rest into.
The focusing knob is of average size. It focuses counterclockwise from close focus to infinity in approximately 1.5 rotations with an extra half turn beyond infinity. This could be considered a little slow to average by today’s standards. What I have found though is you cannot judge a binoculars’ focusing speed based strictly on the number for rotations. You also have to factor in the amount of tension in the focusing knob. Too much tension coupled with too many rotations and the focus can be painstakingly slow. I can happily report that the focusing tension on the VGA HD is not excessively stiff and as a result the focusing speed/tension combination is not slow. This combination actually has a bit more precise feel to it. Minimum close focus for this model is right at 7.5 feet for my eyes.

The eyecup design is something I am a little excited about. Though I have seen similar designs in previous years I have to say that this is the most positive feeling design I have encountered recently. The eyecups are of the typical rotate out/in design. Where they differentiate themselves from other designs is in the mechanism that allows them to stay put at the predetermined settings. As you rotate the eyecups out they go a millimeter or two past the preset distance and then rotate forward again to lock into place. You cannot accidentally move the eyecups from the pre-set position. What an awesome feature. For those concerned about needing an eye relief setting between the predetermined ones there is more than enough tension in the eyecups to keep them set in place. For my use I need to have the eyecups moved out to the first setting from completely collapsed. This leads me to believe that eye relief is very generous.

No issues with the central hinge tension. It isn’t overly stiff but will not accidentally move during regular use. The diopter adjustment is located on the central hinge of the binocular and is of the “pop-out-to-adjust-pop-back-in-to-lock” design. I have not had any issues with it moving accidentally.

Optical Performance:

So the question that most of you should be thinking, at least in my opinion, is “So just how good optically is Opticron’s flagship model?”

I am glad you asked that.

It is good. Very good as a matter of fact. On axis performance is as good as any binocular I have had the privilege to look through in the last year including some of the most expensive consumer binoculars on the market.
So what stands out to me as I look through this binocular?

Well, the first time I used it I was on a pelagic birding trip off the coast of Cape May, NJ. We left the dock around 1 pm and stayed out for 6 hours. I had the opportunity to use the binocular under some very challenging conditions including in low light. In that situation and in every other scenario I have put these bins through I have been struck by their excellent level of apparent brightness, contrast and sharpness. You know that 3D impression that you get when an object is extremely well saturated with color and contrasts beautifully with the background? That is the impression I get with this binocular.

Apparent sharpness, influenced by a variety of factors beyond just resolution, is excellent on axis. The apparent brightness is also first rate. This binocular outperforms everything else I have on hand in low light conditions (assuming a similar configuration). Based on these impressions I am led to believe that Opticron either significantly upgraded the coatings compared to their other models or is using some new type of high transmission glass recently introduced in much more expensive models. Regardless of the origin the effect it has on the image is immediately noticeable. I have compared the VGA to one particular binocular that is advertised as having light transmission numbers in the 90% range and the VGA appears brighter in every condition.

Color representation is completely neutral. I have compared it with two other binoculars I have on hand that display a warm color bias. The VHD looks completely neutral in comparison. I do not have any cool-biased binoculars on hand for comparison.

Chromatic aberration (color fringing) control is excellent on axis….or within the sweet spot if you prefer. I cannot detect it inside the sweet spot. As with most binoculars, as you move away from the centerfield a faint halo begins to appear around high contrast objects. I would call it moderate at the outer edge of the image.

So, in this day and age where edge performance seems to be as much of a selling point as the centerfield performance how does the VGA perform? Well, if there was one area where I would like to some improvement it is in this area. My estimation of the apparent sweet spot size is in the 70-75% range. That is certainly acceptable and actually quite good compared to many models. Having said that it isn’t at the level where many of the more expensive models are at. I feel that needs to be mentioned simply because this binocular competes with those more expensive models in just about every other optical category.

So what is the off-axis performance like?

Well it isn’t poor by any stretch of the imagination. It is quite good actually but when you are accustomed to the high level of performance within the sweet spot then you start to want to have it across the entire field of view. Off axis degradation seems to be mostly a slight amount of field curvature with a little bit of astigmatism as I can’t quite the outer edge as sharp as the sweet spot no matter how I rotate the focus.

The only other optical area that I feel needs improvement is the field of view. At 7 degrees (367 feet) I would call the field of view conservative. There was a high-end model from a well-known Japanese manufacturer that had a 7 degree field of view that nobody complained about but then it also was sharp from one edge of the image to the other. It was also popular about 12 or 13 years ago when field of view numbers, across the market, were more conservative. In comparison to many of the most expensive consumer binoculars the field of view falls a bit short. Its closest competition has a field of view that is about 20 feet wider at 1000 yards. The good news though in this case is that when used on its own the 7 degree field of view does not feel restrictive. Only when comparing it with much wider field of view binoculars do you begin to see a bit of the limitation.

Conclusion:

This model was designed to perform against much more expensive binoculars not only in a variety of optical areas but also in terms of build quality. It falls a little short in one area, field of view but the other optical performance areas make you want to forget about that issue. Ergonomically and mechanically it is a very good Japanese-made binocular. It certainly competes well with anything I have seen priced at or under $1000.

Phonescoped picture out of my office window. Very foggy day so not the best representation in terms of brightness. I will add a better picture at a later day/time.
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Old Saturday 9th January 2016, 08:06   #2
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Frank,

Thanks for the excellent report.

The DBA VHD has replaced the DBA S-coat Mg in the Opticron lineup. I was able to spend a few minutes comparing the two a while back. The old model was really a very good binocular and although the differences are subtle it was nice to see that colour, contrast and particularly CA had improved but I can't comment beyond that. I have a comparatively narrow IPD and I'm not sure the dual hinge worked that well for me but understand others like it. I thought a very useful upgrade.

I hoped to have a more considered look when I stopped by their Luton HQ a few weeks back.... but they couldn't find one for me to try!

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Old Saturday 9th January 2016, 13:32   #3
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Frank,

Good review!

Do you know if the Opticron "Oasis" prism coating means it is dielectric? If so the binoculars must be pretty bright.

The Japanese binoculars you mention above which have the same 7º FOV as the 8x42 DBA VHD also have a flat field and still use silver coated prisms but they are probably state of the art silver coatings. My 8x32s are pretty bright.

Bob

Last edited by ceasar : Saturday 9th January 2016 at 22:06. Reason: rewrite a phrase
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Old Saturday 9th January 2016, 20:50   #4
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Nice job as usual Frank. I had to hold off on reading this until just now and I just finished the review I'm going to post shortly on the DBA HD 10x42. Seems we pretty much agree with this binocular. I wanted to get mine done before I read yours as to not effect mine.

Ceasar, the Oasis is a singly applied layer by layer low temperature process. It seemingly meets dielectric definition, but I don't know if there is a temperature level needed to differentiate cold temp from higher temp as to one being dielectric and the other not. Looks like the same sort of technology Swift used with their Cold Fusion Technology, and what Leupold uses with their L-coat system. I address this a little in the 10x42 review.
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Old Monday 11th January 2016, 12:47   #5
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Thank you all for the kind words.

David,

I look forward to seeing further comments from you once you get your hands on one again. With repeated use in direct comparison with other models the apparent brightness is what really jumps out at me, especially in low light conditions. Saturday morning I had the opportunity to compare the VHD against two other 8x42s at first light...or barely first light as it were. Between the increase in apparent brigthness and the greater contrast I could more readily pick out some waterfowl moving across the lake...even with a bit of fog in the air.

Bob,

I would agree with Steve's comments. Back when I first started reviewing Opticron's products I asked them what all of the proprietary terms they used for their products would equate to in more commonly accepted terminology. I was told that the Oasis coating was basically dielectric. I think there is more to the increase in apparent brigthness than that though. They have used an Oasis coat for quite some time and I have tried other models that featured it. I don't ever remember being as impressed with the apparent brightness of those models in comparison to this one.

Steve,

I look forward to reading your 10x42 review. I briefly handled the 10x42 back in October but don't remember much about it. For the most part I would expect to hear that you found similar conclusions to what I did.
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Old Monday 11th January 2016, 16:15   #6
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I did receive a message from the manufacturer addressing my field of view comments in the review. It is copy/pasted below:

Quote:

"While it is technically possible to deliver a wider FOV, 7 degrees was
decided upon as it gave a what we saw as a good balance between FOV and
resolution with the chosen prism set. A wider FOV with similar resolution
figures would necessitate using a larger prism set with an associated
increase in body size and weight. This change would negate many of the
advantages the compact 42mm format delivers for the VHD"
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Old Tuesday 12th January 2016, 07:26   #7
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I did receive a message from the manufacturer addressing my field of view comments in the review. It is copy/pasted below:
Frank,

"Smaller, Lighter, Brighter, Sharper" is very much the Opticron motto and most of their x42 are several ounces lighter than many of their competitors. Prism size would would be part of that. There appears to be another factor too. Like a number of the Opticron models the DBA VHD 8x42 has a rather long ER at 22mmm. For a given eyepiece design, increasing the ER will result in a narrower view. I'm happy with 15 or 16mm with my glasses but I know some need more. If the ER was reduced to 16mm it would potentially have a 465ft view, though I guess the small prisms might cause significant vignetting. Interesting prospect though!

David
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Old Tuesday 12th January 2016, 10:56   #8
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Yes David. I would agree. I said much the same thing about the company motto in my reply email. Unless resorting to much more sophisticated and expensive designs it would be difficult to follow that motto and still produce some aspects of optical performance that are popular in the market.

I guess the compromise is that we can give you high end performance in almost all areas and at a reasonable price but it is going to cost you in field of view.
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Old Tuesday 12th January 2016, 11:30   #9
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Quote:
Originally Posted by typo View Post
Frank,

Thanks for the excellent report.

The DBA VHD has replaced the DBA S-coat Mg in the Opticron lineup. I was able to spend a few minutes comparing the two a while back. The old model was really a very good binocular and although the differences are subtle it was nice to see that colour, contrast and particularly CA had improved but I can't comment beyond that. I have a comparatively narrow IPD and I'm not sure the dual hinge worked that well for me but understand others like it. I thought a very useful upgrade.

I hoped to have a more considered look when I stopped by their Luton HQ a few weeks back.... but they couldn't find one for me to try!

David
Are you sure it has replaced it? Doesn't look like it from the Opticron website.
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Old Tuesday 12th January 2016, 11:44   #10
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Yes David. I would agree. I said much the same thing about the company motto in my reply email. Unless resorting to much more sophisticated and expensive designs it would be difficult to follow that motto and still produce some aspects of optical performance that are popular in the market.

I guess the compromise is that we can give you high end performance in almost all areas and at a reasonable price but it is going to cost you in field of view.
I have used the DBA (MG) 8x42 for about two years in a diverse range of settings, forest, moorland, coast etc. I have periodically been tempted towards an upgrade and have on occasion compared it against the Zeiss HT and very recently the Leica HD plus in truth there was not much difference in 'the view', perhaps they were a little brighter but nothing more. CA was just as well controlled. I find the ergonomics and focus equally good, the focus in particular is excellent on the DBA. As mentioned here the only marked difference is FOV. I am personally not much bothered with this and certainly not to the extent of spending three times as much on upgrading where I doubt it would make a great deal of difference to my birding. I have always felt that this binocular was unfairly overlooked. Perhaps the stimulus of a new model (I have not tried one yet) will go some way to rectifying this

Barrie
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Old Tuesday 12th January 2016, 11:46   #11
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Jinty,

Yes, it has been replaced. I don't see it on the UK or US webpages.
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Old Tuesday 12th January 2016, 12:11   #12
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The DBA S-Coat models have been discontinued, and have been replaced by the new DBA VHD. As ever when a new model is introduced there will still be some retailers that still hold stocks of the DBA S-coat
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Old Tuesday 12th January 2016, 20:39   #13
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They S Coats were only removed from the website in the last few days hence the confusion.
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Old Sunday 17th January 2016, 14:10   #14
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Frank what are the exit pupils like on yours? My friend about a VHD yesterday and both pupils were severely truncated. Not good enough for a supposed premium binocular. Clearly the QC is not robust.
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Old Sunday 17th January 2016, 14:42   #15
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Allbinos has one review of 8x42 Opticrons. The Countryman 8x42 BGA. I don't know how similar this binocular's optical construction is to the DBA VHD 8x42 but Allbinos also criticizes its truncated pupils and they don't look very good. They note that the main aberrations are corrected well.

I guess this is one of the prices you have to pay to keep the size of the binocular down.

http://www.allbinos.com/248-binocula...x42_BGA_T.html

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Old Sunday 17th January 2016, 17:11   #16
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FWIW, the 10x42 bears no resemblance to the review of the Countryman. The exit pupils on my example are not truncated and there are no internal reflections in the view as seen in the picture of the Countryman in the review.

In my view, comparing the Countryman to the DBA VHD based on the Countryman review is not even an apples to oranges comparison. That they are two very different binoculars seems pretty obvious to me.

I'd have no problems with a DBA VHD as a personal use binocular.
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Old Sunday 17th January 2016, 18:07   #17
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I agree. That review is also for the older Countryman. However, the exit pupils on the model I tried yesterday were shocking and a total disgrace. £589 is a lot of money. Helios and Celestron can make binoculars at £95 with perfectly round exit pupils. Why can't Opticron do it at circa £600? Not good enough.
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Old Sunday 17th January 2016, 18:29   #18
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I agree. That review is also for the older Countryman. However, the exit pupils on the model I tried yesterday were shocking and a total disgrace. £589 is a lot of money. Helios and Celestron can make binoculars at £95 with perfectly round exit pupils. Why can't Opticron do it at circa £600? Not good enough.
They got the exit pupils perfectly round on my sample. I would note samples of one do not reach the level of insignificance either.
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Old Sunday 17th January 2016, 22:23   #19
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FWIW, the 10x42 bears no resemblance to the review of the Countryman. The exit pupils on my example are not truncated and there are no internal reflections in the view as seen in the picture of the Countryman in the review.

In my view, comparing the Countryman to the DBA VHD based on the Countryman review is not even an apples to oranges comparison. That they are two very different binoculars seems pretty obvious to me.

I'd have no problems with a DBA VHD as a personal use binocular.

I assumed we were talking about 8x42 binoculars here which is why I compared the review of the Opticron Countryman to the Opticron DBA VHD on the issue of truncated exit pupils. It is the only Opticron 8x42 binocular reviewed by Allbinos. I also made the assumption that they used the same sized roof prisms.

Your 10x42 has smaller exit pupils than an 8x42 has. It is possible that they would not be truncated. Using the same prisms on an 8x42 binocular
could show truncation.
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Old Monday 18th January 2016, 13:54   #20
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Frank what are the exit pupils like on yours? My friend about a VHD yesterday and both pupils were severely truncated. Not good enough for a supposed premium binocular. Clearly the QC is not robust.
I will check later today and let you know.
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Old Monday 18th January 2016, 14:31   #21
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I agree. That review is also for the older Countryman. However, the exit pupils on the model I tried yesterday were shocking and a total disgrace. £589 is a lot of money. Helios and Celestron can make binoculars at £95 with perfectly round exit pupils. Why can't Opticron do it at circa £600? Not good enough.
Jinty,

Just curious why you might be concerned by the shape of the exit pupil. Seems numbers were around 3% light loss for those old Countrymans which would really come into play when viewing by moonlight and those VHDs are still going to be up to 35% brighter than a £90 Helios or Celestron at all light levels. If you think can spot 3% difference by moonlight look at heavier models with bigger prisms, but you would actually be much better off with an 8 or 10x56 anyway.

David

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Old Monday 18th January 2016, 20:37   #22
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Jinty,

Just curious why you might be concerned by the shape of the exit pupil. Seems numbers were around 3% light loss for those old Countrymans which would really come into play when viewing by moonlight and those VHDs are still going to be up to 35% brighter than a £90 Helios or Celestron at all light levels. If you think can spot 3% difference by moonlight look at heavier models with bigger prisms, but you would actually be much better off with an 8 or 10x56 anyway.

David
Typo,

In your opinion, is it acceptable for a £600 binocular to have truncated exit pupils?
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Old Monday 18th January 2016, 21:59   #23
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Typo,

In your opinion, is it acceptable for a £600 binocular to have truncated exit pupils?
I've seen it at all price points including the alphas. I just can't imagine a situation where something like 3% reduction in EP area would make any practical difference, so it's the very bottom of my list of criteria.

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Old Tuesday 19th January 2016, 06:14   #24
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I've seen it at all price points including the alphas. I just can't imagine a situation where something like 3% reduction in EP area would make any practical difference, so it's the very bottom of my list of criteria.

David
It shouldn't happen at any price point. I imagine there's an issue with internal construction if they are truncated? Could you provide any documentary evidence that shows the figure to be approximately 3%?
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Old Tuesday 19th January 2016, 07:08   #25
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Jinty,

I was just using that old Countryman result as an example which gave the right side as 2.67%. I've seen many with oval exit pupils which is perhaps less obvious, but are clearly higher than that with some examples. It's not something I routeinly check anymore because I don't regard it as important but I didn't notice anything exceptional about the VHD I tried.

I've never been brave enough to take a roof model apart, let alone an Opticron, so I can't tell you how the mounting and collimation is adjusted. I know the roof prisms are usually assembled in a separate casette and I'm sure there must be a 3 or 4-axis ajustment mechanism. Collimation is very important. There can be 6-12 lenses in the optical path and I think prism orientation is the usual method of compensation for any initial misalignment. It it is necessary to tilt the prism casette it will result in an oval EP. With a compact light weight binocular with small prisms there is a risk of touching a prism edge. If its a few percent of the area I regard it as inconsequential.

The Kite Bonelli 2.0 boasts a "large prism format" and is over 800g and the VHD under 700g.

David

Last edited by typo : Tuesday 19th January 2016 at 20:26.
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