This is a copy of a post I recently left in another thread. I thought it might be equally relevant here:
I recently got my pair of Canon 10x42L IS binoculars. I have been very curious to see just how Canon's best "L" glass would compare to Europe's finest. IS aside, these are phenomenally good optics! If Canon decided to forego the IS, and simply re-package these optics in a sleek and lightweight housing - this might be THE finest binocular on the market. They are bright, sharp across the entire field, free of chromatic abberation and completely free of flare in even the most difficult lighting. But alas, Canon is synonymous with Image Stabilization in the binocular world - and this is their undoing. Thanks to IS, they are overly large and heavy, and worse yet, an ungainly shape that doesn't seem to have been made to be comfortably held by human hands. The price of image stabilization is an image that is constantly fluctuating into and out of perfect focus, due to the constant high-frequency movement of the prisms as they "Stabilize" the image. In fact, we have simply traded one annoying optical artifact (image shake) for another (a disquieting image instability). Since most of us have unintentionally trained our brains to compensate for a certain amount of image shake, this new and unaccustomed phenomenon is just bothersome. In order to keep the image critically sharp, it is still necessary to concentrate all ones efforts on holding them steady - but this is a bloated, overweight contraption - so doing so is even more tiresome than without IS (and all that comes with it) at all. It's a shame, really - this may be the finest set of optics I have ever sold.
