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Suitable bins for under £70?


sevs23

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Hi

I'm looking for a new pair of bins for anything under £70. I have a pair of Soviet made 12x40's, but these are rather precious to me so I'd like a new pair for casual star gazing.

I've has Celestron 15x70's but they're too big & heavy

Something like 10x50's...Any recommendations?

THxs

Steve

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I spent a little more (£105) on a pair of Bushnell Legend 8 x 42 Porro Prism bins and love them, they are light enough to hold up with one hand and give excellent sharp bright views, and are very well armoured.

It looks like these are no longer available, I would guess their replacement might be these: BUSHNELL H2O 8X42 PORRO BINOCULARS: Amazon.co.uk: Electronics but I have no knowledge of this particular pair.

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I wouldn't normally comment in threads like this but FLO doesn't offer binoculars at around £50 so hopefully people will accept this advice as neutral and objective.

I don't understand why the Olympus 10x50 DPS-I is getting so much positive attention. It sells for around £50. Checking the specs at the manufacturer's website it appears to be a straightforward 10x50 binocular with mono-coated optics and, probably, Bk-7 prisms. Looking at the wording it would also appear not all air-glass surfaces benefit from the single layer of anti-reflection coating.

Olympus - 10x50 DPS I

You can do better.

For example, the Helios Fieldmaster 10x50 selling for £47 from Harrison Telescopes (one of our competitors).

Helios Fieldmaster 10x50 Binocular

It offers fully multicoated optics and Bak-4 prisms.

I know which one I'd choose :D

Hope that helps,

Steve

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I'd have to agree with Steve on this. I feel that BaK-4 prisms and FMC optics are highly desirable and quite attainable even at a modest budget if you look around.

Take a look at this guide by Alan MacRobert of Sky & Telescope magazine:

Sky Publishing - Choosing Binoculars for Astronomy

His third point under the "Testing Binoculars" heading refers to looking for a uniformly illuminated and round exit pupil as a sign of good quality prisms. BaK-4 prisms deliver this wheras BaK-7 ones cause edge cutoffs which are quite obvious when you test the binoculars as Alan suggests.

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I don't understand why the Olympus 10x50 DPS-I is getting so much positive attention. It sells for around £50. Checking the specs at the manufacturer's website it appears to be a straightforward 10x50 binocular with mono-coated optics and, probably, Bak-7 prisms. Looking at the wording it would also appear not all air-glass surfaces benefit from the single layer of anti-reflection coating.

Well, while they don't tick all that many boxes, I'm going to guess much of it's success is due to word of mouth, at that price point more people can afford a pair. At which point there are more mouths saying they were impressed. What Oly don't exactly shout about, and I am guessing a lot of people miss, but which is, none the less, in the spec is that they are also aspherics. I'd imagine this is what could be impressing a lot of people without them even realising why they like them so well. So, in presenting a perhaps more pleasing image to the end user, people are then in a position to be telling others that they like them as they seem somehow better to them, and that they like the way they are, more than with other types.

It may not make them better, but it has perhaps made them more widely appreciated than other types. Since optical industry success is very much volume driven, perhaps more makers might like to think more often about how they can make things more pleasing for the end user, rather than just doing the more usual, market research lead, box ticking exercise at the design stage.

Nearest aspherics I currently know of are a clear £19 plus delivery more than these and for only 8x40 versus the 10x50 Olys. There could, of course, be others but I just don't happen to have noticed them yet.

It's a little bit like VHS and betamax all over again really.:D

Of course this is just speculation on my part, and I could be all wrong too. Something sure is causing the anomaly though, they are very popular, well liked and much spoken of, and I'm guessing that this contradiction of the norm is what perhaps brought it to your attention too. It flies in the face of what we may have thought before.

One should also not forget that Oly are a very big name in optics, and they have been known to make very good glass indeed from time to time, in the view of many. That must have some bearing on it all. They are certainly still on my short list. If Amazon were not selling Olympus but shipping Coleman brand in their place I'd perhaps have ordered a pair too by now. I may even stop being concerned about that in the next week or two as well.

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What Oly don't exactly shout about, and I am guessing a lot of people miss, but which is, none the less, in the spec is that they are also aspherics. I'd imagine this is what could be impressing a lot of people without them even realising why they like them so well. So, in presenting a perhaps more pleasing image to the end user, people are then n a position to be telling others

If you own the binocular and are enjoying the views then that is good :D

My comments are aimed at those who don't yet own one and are weighing up their options.

Aspheric elements in eyepieces can be good, depending on how they are made and why they are used. Their main role is to correct spherical abberation (in that sense they are similar to a parabolic mirror in a Newtonian telescope). Done properly they are said to increase contrast, definition and even apparant brightness. But, glass aspheric lens surfaces are significantly more difficult (expensive) to manufacture than simple spherical ones. Some manufacturers employ a hybrid aspheric lens where a moulded resin aspheric surface is bonded to a glass element. Hybrid aspherics are not quite as expensive as glass aspherics but can still offer high performance. At the more affordable end of the market the aspherics are simple moulded plastic and are used as a cheap alternative to extra lens elements.

Hope that helps,

Steve

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If you own the binocular and are enjoying the views then that is good :D

Oh, now can't life be a little ironic from time to time. As I wrote I had never even laid hands on a pair of them, however in explaining what I felt might be going on to you, I refocused on the whole thing, and thought to myself, "Aspherics, in a recession, for this price, from a very big name, I could always send them back hassle free if they are actually no good, they even send a courier for them at no cost if that hapens". And so while you were replying I was in fact placing an order with Amazon so I can try them first hand and see what all the fuss might really be about. :cussing:

My comments are aimed at those who don't yet own one and are weighing up their options.

Well I was in exactly your target group at that time. Life can be so odd at times.:clouds1:

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Iv been looking for a pair last few weeks. And I thought about eBay. Yes I know it's not the best but a pretty old pair. Like the ones the OP mentioned he has like leica or Carl Zeiss zuis.

If you know your binoculars then you can sometimes pick up a baragain. Early Russian and East German Zeiss Jenoptem and Deltrintem binoculars are good places to start but they can fetch high prices because people confuse them for West Zeiss.

Life can be so odd at times.:clouds1:

It certainly can :D

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Some interesting comments. Allow me to add my £0.02:

Firstly, as far as I know, the Olympus DPS1 does not use BaK7 prisms. In fact, I don't know of any binocular that does. Some use BaK6 but, IMO, that is just a gimmick for two reasons:

  • You just don't need the extra refractive index over BaK4 (the critical angle for BaK4 is sufficiently low)
  • BaK-6 has higher chromatic dispersion than BaK4, so that is potentially degrading to the image.

BaK7 has significantly higher chromatic dispersion than BaK6, so it would be even worse in this regard. I know that idiocy abounds in "binocular land" but I really can't see any manufacturer going for the greatly increased expense of BaK7 (compared to BaK4) if the net result is going to be to degrade the image. (But don't take my word for any of this -- do the maths/raytracing for yourself!) But, even if they did use BaK7, you would not get grey segments ("edge cutoffs") in the exit pupil, because the of the high refractive index of BaK7 (compared to BaK4). I haven't done the maths, but I would be surprised if you got "edge cutoffs" with any of the Barium Crown glasses, even BaK1 (which has the lowest refractive index of the Barium Crowns).

Secondly, FMC can be over-rated. If it is properly applied, it is very effective but, if quality control is inadequate (as it often is with budget binoculars), it can be even less effective than a properly applied single-layer anti-reflective coating.

Thirdly, even if a binocular does have BaK-4 prisms and properly applied multi-layer coatings, it still need not be as good as one that has only single-layer coatings and which uses Borosilicate Crown (BK7) prisms. The German (as opposed to far-Eastern copies) Zeiss Jenoptem 10x50 (BK7 prisms, single-layer coating), for example, is noticeably brighter than many of the budget FMC/BaK4 budget 10x50s. The Dekarem is even better. The reason is simple: the budget ones tend to have dire internal "stopping" -- measure the exit pupil of the Bresser so-called 10x50 and its clones, and you will find that it is you really have a 10x43!

I realise that it possibly appears that it's becoming a mantra for me to say this on these forums, but there are aspects of optical and mechanical quality that are at least as important as labels on the cover-plates saying "FMC" and "BaK4". The internal "stopping" is one; others include crispness of focus, flatness of field, edge distortion, chromatic aberration, build quality, smoothness of focus...

Ultimately, the only way you are really going to be able to tell is by looking through the things yourself and seeing what suits you. I tried the Oly DPS-1 some while back, and I recall being pleasantly surprised (but not so impressed that I bought it at the price it was then :D; I don't recall what the prisms were but, as I say, I'm far more interested in overall mechanical and image quality) -- better built and flatter, clearer images than the Bresser I mentioned above (but the QC is so incredibly poor on that...). I have not had my grubby mitts on the Helios Fieldmaster, so I can't comment on it.

Best advice: read reviews, try a few to compare, and buy/keep what you like.

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Firstly, as far as I know, the Olympus DPS1 does not use BaK7 prisms. In fact, I don't know of any binocular that does.

Bk-7 prisms are in common use in the budget end of the binocular market. Bak-4 is preferable and is more likely to achieve a fully illuminated exit-pupil.

The difficulty with discussions like this is there will always be exceptions to the rule. We need to generalise if we are to increase understanding and avoid confusion. I agree there are a number of components to consider and it is fair to say manufacturing quality is upper-most.

HTH,

Steve :D

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Bak-7 prisms are in common use in the budget end of the binocular market.
No, it isn't. BaK7 is an expensive, high refractive index (hence low critical angle) Barium Crown glass. The budget end traditionally uses BK7, which is a cheap low refractive index (hence higher critical angle) Borosilicate Crown.

Edit: Just been looking up some glass data & have found some rather "interesting" stuff with respect to the qualities of Chinese BaK4. More in another thread when I've digested and ordered it.

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Edit: Just been looking up some glass data & have found some rather "interesting" stuff with respect to the qualities of Chinese BaK4. More in another thread when I've digested and ordered it.

Let me guess, some manufacturers are using under-sized Bak-4 prisms to reduce cost while continuing to quote "superior Bak-4 prisms".

It's a jungle out there :D

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Let me guess, some manufacturers are using under-sized Bak-4 prisms to reduce cost while continuing to quote "superior Bak-4 prisms".

It's a jungle out there :D

Not that (but it does happen) -- I'm pretty sure that what is being hawked as BaK4 is "not BaK4 as we understand it, Jim". :clouds1: (Be patient, I'm getting there!)

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