Why is eyeglass compatibility important when choosingbinoculars for birding?
If you wear eyeglasses, then you should leave them on when using binoculars. You will find many models which are eyeglass friendly.
Look for binoculars that are described as having long eye relief. Long eye relief means that the optics direct the focal point further back behind the eyepiece so the eyeglass wearer can see the complete field of view. The amount of eye relief can be found in the model's technical specifications. Eye relief of 12 to 15mm will provide the best results.
Non-eyeglass wearers should use the binoculars with their eyecups in the raised position. Some designs have folding rubber eyecups; other designs snap up and down. The recently developed turn-and-lock style of eyecup works well. Try binoculars with various eyecup styles and ee which works best for you.