OK, there’s no perfect fix, everyone’s requirements vary, so here’s some of the basics to consider.
Every binocular has two numbers, for example 10×50 or 8×21.
The first number tells you the magnification, a 10×50 makes whatever you are looking at appear 10x
closer, and 8×21 makes everything appear 8x bigger or nearer. The bigger the first number, the more
powerful the binocular.
The second number tells you the size of the front (objective) lenses, 10×50 has 50mm lenses, the
8×21 has 21mm lenses. Basically the bigger the better as bigger lenses let in more light and can make
the image brighter.
So, there’s always a temptation to buy a really big magnification to make your subject look really
close, but this is usually a big mistake. With big magnification comes 3 problems.
Firstly, with more magnification there is a much reduced “field of view” so you see much less of the
thing you are looking at, and it makes it hard to find it in the first place.
Problem number 2 is holding the binocular still, higher magnifications are very difficult to handhold
without the image shuddering and shaking. Most people can hand hold up to about 12x
magnification, but above this you really need a tripod to support the binocular.
Problem number 3 is how bright the image is. Higher magnifications effectively use up light so the
image on a 12x binocular may not be a s clear and bright as an 8x.
Bigger lenses do let in more light, which helps to lessen the brightness problem at higher
magnifications, but bigger lenses means much more size and weight to carry.
For most practical use such as birdwatching, nature and sports, you’ll need a good wide field of view
and modest magnification, I would suggest around 8x or 10x. If you don’t mind wearing the
binocular around your neck then a binocular with around 40mm – 50mm lenses will be OK and not
too heavy, so try out some 8×42’s or 10×42’s .. or if you want a little more brightness for low light
then perhaps a 10×50. If your hobby is is aircraft spotting or ships at sea, then you may need a little
more magnification, try a 12×42 or 12×50.
This is just a brief outline of some of the matters to consider, you’ll find full details on the technical
sections of our websites