Really off topic, but,

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epervier

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Motor boaters use them, Binoculars, I'm absolutely out of my depth here, the range and choices seem to be endless, /forums/images/graemlins/confused.gif

Can the panel recommend a good allrounder that doesn't cost a mortgage, while you're thinking about that, has anyone the time to explain the various sizes, 10x42, 10x50, 8x25, etc.
 
the first figure is the number of time that the object you are observing is magnified. The bigger the magnification, the more the image will shake and move about as you look at it.

the second figure is the diameter (mm) of the objective lens (the one away from your eyes).

If you have a big magnification, then you are "sharing" the amount of light that the bins can gather in the objective lens, so a large mag and small obj lens means a dull image.

The classic way is to take the square root of the objective, and divide it by the magnification.

So..

10x50. Root 50 is (roughly) 7, divided by 10 is 0.7
7 x 50 ditto........................, divided by 7 is 1

The larger the final number, the brighter (and to a certain extent) clearer the image will appear.

So a little old 8x25, gives 5/8, so a "light number" of 0.6.

For starters, until you become throughly familiar with the use of bins, I'd suggest you wait till Aldi or Lidl have one of their special offers, and go for a 7x50 at around £20.

Or you can buy my Pentax military fixed focus 7x50 for lots and lots of pennies /forums/images/graemlins/grin.gif
 
I've been very happy with my Canon 10x42 bins.

Waterproof and with image stabilisation which makes a HUGE difference. Other 8X plus bins are like looking through while an earthquake is going on. With image stabilisation, it feels like looking through a NASA tracking device. It does add some weight however.

Bit more expensive than Aldi tho.
 
I stand to be corrected, but when I was at sea 7x 50 was all I can recall being used and was told that anything more powerfull required a steady platform to get a clear image also this magnification gave the best all round results for clarity. Personally I have found that to be true after using a slighly more powerfull type, bought a cheap pair with built in compass, which when you get used to it can be off great use.
 
There is a review in Sailing Today. All 7x50 which is the best for use at sea. They said Plastimo is a good cheaper model at about £70.

They did not find much optical difference with more expensive types but they are likely to be more durable - but up to £800! And the compasses were better.
 
I've always found 10 x 50 to be the best for me - and they are what I used in the old days with Blue Star.

Had a look through a friends really expensive binoculars a while ago, and the difference is amazing, but at about £800, you would expect it to be.
 
A bit of a bonus @ force 4, the binos were £29.99 they were old stock with old price still on them,

Mind you, how is it when you go to chandlers you always somehow manage to spend more than a hundred quid, todays outing £109 and change /forums/images/graemlins/frown.gif /forums/images/graemlins/confused.gif /forums/images/graemlins/shocked.gif /forums/images/graemlins/grin.gif
 
Don't forget the tip regarding the trueness of the prisms inside the binoculars (often the achilles heel of cheaper ones).

Reverse the glasses and hold them at arms length, look through the object lenses and adjust them so you are looking at the horizon.

Good glasses will have the two 'horizons' in a straight line and poorer ones will have a noticeable difference between the two lines. This discrepancy will cause eye strain in the end.

Tom
 
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