I have recently developed an interest in birding and received a 12x42 binoculars as a gift. A lot of articles online mention that 8x42 binoculars are the best for birding. How useful is 12x magnification for birding while hiking?
They would be good on a tripod at an open shore line looking at shore birds but professional tend to use higher power for those circumstances . Most people would need to brace against something like a tree to steady 12 X. The 42 mm objective has low light gathering for such high mag ,so they will only be useful on bright days, not dawn or dusk. I would suggest the typical binoculars for beginners 7 X 35 , although I used 7 X 50. Although big and heavy the 7 X 50 are good in a dark woods and dusk and dawn.
What binoculars you choose depends what you're doing with them as much as what you're looking at (birds). If you're hiking a long way, lightweight is good, meaning less glass; you might carry 8x25s. If you're out at dusk, you need all the light you can get, and 8x42 or 10x42 would be good. If you're looking at things a long way away, often the case with birds on or near water, higher magnification is good, i.e. 12x (anything more isn't usually good handheld, and a scope is preferable).
I have or have had in the past 8x20, 8x25, 10x25, 10x30 and 12x50. The last pair is closest to what you've got, and was bought for dawn and dusk game birding and safaris. They're very useful at longer ranges.
Things to watch out for (assuming you basically get on with them for things like ergonomics and eye relief) include:
- Close focus. 12x binoculars often don't focus close enough for backyard birding and some hides that the birds approach very closely.
- Finding the bird can be hard if there's too much magnification - lots of scanning and by the time you've found where it was, it's gone. My 12x50s are basically useless for birds in flight unless soaring.
- Optical quality. You don't give any idea of whether they're entry level or the very best. Even cheap binoculars are much better than they used to be, but higher magnifications are more prone to imaging flaws (especially chromatic aberration, but also a softening of the focus at the edges).
As you say you're fairly new, there's another benefit to 12x - you'll probably rely more on visual identification than on behaviour or calls (like me, though I'm getting better at the latter). 12x allows for a better study of the bird's appearance
In the Olde Dayes of big, bulky, traditional Porro prism binoculars, the rule of thumb for birding binoculars was that you needed an exit lens:power ratio of about 5 for best results.
The power is the 7X or 8X or 12X number (indicating how much magnification it provides) and the exit lens size is given by the other number: 35 or 40 or 50 or whatever.
Higher power gives you larger, but 'shakier' images, meaning that it's harder to hold the binoculars steady enough that movement which would have been no problem at a smaller power becomes troublesome when the bird looks bigger. 10X is about the largest size you would consider for birding in a Porro prism unit, and unless it's a good model, that's in kind of a grey area for most of us who don't have big strong hands and wrists.
Larger exit lens gives you more light-gathering and bigger field of view, helping to counteract the effect of higher power.
Nowadays, with the smaller, lighter, roof-prism binoculars, that rule has been relaxed a great deal, and the old traditional 7X35, 8X40, 10X50 sizes have been expanded to include a wide variety of "weird" combinations. 12X42 is still a bit high for my taste, but it might prove useful for duck-watching or shorebirding when you don't have a scope.
Regardless of any Basic Rules, though, the big thing about binoculars is how they feel in your hand, how quickly you get them on the bird, and how easily you can do things like focus. I have big, clumsy hands, so I really liked the old Audubon 8.5X44 Porro prism binoculars, but times change, and now I have a pair of decent (largish) roof prism binoculars with a good, fast focus knob and the ability to focus in close and then back out again reasonably quickly during warbler season (which runs from early spring to late fall, more or less). By all means listen to recommendations, but there's no substitute for actually trying them out in the field to see how well they work in your hands.
So, to sum up, although I wouldn't pick 12X42 as a model for birding, you might well find that these suit you perfectly. Since they were a gift, what you might try is to get a decent set of $100-$200, more general purpose 7X or even 8X binoculars, after getting recommendations and seeing if you can try out some of the models just to weed out the ones you find aren't what you want. Then you can use the low power one until you know how it feels, and try the high power gift one to compare it to your new baseline.
Whatever you pick, you'll find that the binoculars you use can have a very powerful effect on your enjoyment of birding, so you'll want to take your time and get used to what you have for a while. That way, when you try out a different model and it makes you go "whoah!", you'll know whether it will be worth it to take out a loan..