Years ago, I bought an inexpensive wide-angle 7 x 35 binoculars with a 'rocker' focus. It has proven to be a very good choice for bird watching. The key here is wide angle and not too much magnification. This binocular is smaller and easier to handle than a 8 x 50 or 10 x 50 and the image is not jittery. It is a little less bright than an 8 x 50, but is bright enough. A 10 power binocular is difficult to use because a person can not hold it steady enough to calm the image and its narrow field of view makes it difficult to track a bird in flight.

If you wish to get a close view of birds at your feeder from inside your house, make sure that the binocular can focus close enough. Many binoculars can not focus on objects closer than 15 to 20 feet. The general rule is the higher the power, the greater the distance of the minimum focus distance.

Calculate a 'guide' number to judge potential brightness for comparisons. Use an 8x50 as standard. The guide number is 50/8 or about 6. The guide number for 7 x 35 is 35/7 or 5. Thus you could expect the 7x35 to be a little less bright than the 8x50 (power x objective diameter).

Having a rocker focus (quick acting) rather than turing a knurled nut is a very useful feature for bird watching, although these tend to be a bit more wobbley than the nut type.

For birding, you will need a binocular that operates in cold weather. Some cheap units masks loose fitting focusing parts with thick grease. This lubricant can get very stiff in the cold.

I do not recommend buying binoculars on-line because you need to handle the binoculars before purchasing. The one exception to this is if you are buying a known brand and model with which you are familar.