8×42 vs 10×42 birding binoculars: wider acquisition or more distant image scale
Choosing between 8×42 and 10×42 binoculars for birding is not a free upgrade from less magnification to more. Holding the 42 mm objective size constant, 10x gives more image scale while 8x often gives a wider viewing window and makes hand movement less conspicuous. Exact field of view, eye relief, close focus, weight, and fit