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what binoculars?


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Raven- I'm not an expert but I do know that the more information you give in a question the easier it is for people to give advice.

I can try and give some general info.

1. Large magnification binoculars are difficult to use without a tripod ( the magnification figure is the 1st one i.e 10x50) the object you are looking at will appear like a pinball. 10 or 12 mag is plenty for handheld.

2. Try to avoid some of the cheap rubbish you see on ebay (often made in China) although some of the products being sold by Meade / Bresser are sufficient for the amateur .

What exactly do you want to observe ? I've just noticed this.. have a read there http://stargazerslounge.co.uk/index.php?topic=11104.0

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Raven ,have a look on the German e bay at carl zeiss binns there is a bit more choice than the UK ebay, for this class of binoculars in 10x50 or 12x50 range ,avoid cheap Chines binns not( worth the eye room) better off with a good second hand pair of carl zeiss ,or other top brands Nikon fujinon, ...good binocular hunting :lol:

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I've looked through a few pairs of bins and I don't get on with cheapies. I wear glasses and I must be very sensitive to the slightest defect. The only reasonably priced ones I've found ok, well very good actually, are the Bresser 8x56 and 9x63 linear ones. I find them very comfortable, don't give me eye strain

and a real pleasure to use. Scope and skies were advertising the 8x56 for fifty quid and the 9x63 can be had off an ebay seller for fifty eight.

hope that's of some use

DAve

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Raven,

If the binocular is for astronomy, it is a two-horse race: A 7x50 or 10x50 porroprism. Porroprism (not roof-prism) are the 'classic' design popularised by Zeiss in the 1920's and look like this:

http://www.firstlightoptics.com/proddetail.php?prod=bmontana7x50pp

The porroprism design generally has a larger prism-block with one less reflecting surface. The light path is also less complex and the light is not pulled out of phase (roof-prisms need extra phase-correction coatings if they are to compete). The porroprism design is also easier and cheaper to manufacturer so offers greater quality per £.

In short, those who choose 7x50 (7x magnification) prefer them for their larger exit-pupils (the diameter of the beam of light as it exits the eyepiece and enters your eye). With a larger exit-pupil it is quicker and easier to centre your eye on the eyepiece. Also, the lower magnification means less image shake when hand holding (hand-shake is magnified 7x, not 10x).

Fans of 10x50 (10x magnification) prefer the increase in magnification; they also argue that an exit-pupil greater than 5mm (7x50 offers 7mm) wastes light as our eye-pupil rarely opens wider than the 5mm offered by a 10x50.

As with all things optical, quality is reflected in the price. If you are looking for something disposable - spend £25-£50. If you want brightness, contrast, colour accuracy, a wide-field of usable sharpness and construction that is tough enough to keep the two objectives aligned - spend £100+

Hope that helps :lol:

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Raven, your question is quite open ended but hopefully the following thoughts might be useful.

You don't mention whether this is specifically for astronomical use or for general use including astronomy. If the former, are you intending to "hand hold" most of the time or are you prepared to mount it on a tripod?

If this is for general use, a magnification greater than 10 is likely to be difficult to hold steady for any length of time. I would also look for the aperture to be within the 40-50mm range. The higher end of this range would give you a slightly brighter image which would be better for astronomy, but downside is likely to be a heavier instrument. Whether this is a real disadvantage will depend on how much you intend to carry the binocular around.

If you are looking specifically for astronomical use and are prepared to mount it on a tripod, I would also consider a 15x70 binocular. A smaller binocular just won't show the same detail or such faint stars and I think you would be amazed at the views instruments of this size are capable of providing of subjects such as the Pleiades or Orion's sword. If, however, you only want to hand hold, this size would be impractical; I personally would prefer a 10x50 rather than the 7x50 because the higher magnification should enable you to see more stars and the background should also be darker. But you need to be able to hold the binoculars steady enough.

The other major issue to consider is whether you wear glasses. If you do, AND you suffer from astigmatism, you will almost certainly need to wear your glasses whilst observing. This means you must ensure you have adequate eye-relief. Binocular models can vary quite considerably in this respect.

Other factors to consider include the FOV and the ergonomics of the binocular. For astronomical use I find binoculars with a larger FOV to be much easier to use for the obvious reason that it is easier to find a specific target. Ergonomics are a personal thing and in my view shouldn't be underestimated - if you find something awkward to use, you probably won't use it!

If holding a binocular steady is a problem, "image stabilised" binoculars are available albeit at relatively high cost. There seems to be quite a large following for these instruments despite their exit pupils being smaller than normal for astronomical use. Although I don't have personal experience of these, the comment inevitably seems to be that you see more because the image is that much more steady. Some people, however, find them more cumbersome to use.

Possibly more so than with many other purchases, if at all possible you should try different models out at a good dealer.

Hope that helps,

John

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