Originally Posted By: krismoriah72
She is 73 y/o and not in the best of health. So something one handed that she can put on her lap.
Does she wear glasses or contacts?
Does she have astigmatism?
Cataracts?
If she wears glasses, she needs a bino with a long eye relief so she can see the full field-of-view with them on. Doff/Don with glasses gets old quick when using binos. With astigmatism, a long eye relief optical design will be mandatory.
She needs a model that is light-weight, low power, will close focus and with a wide-field optical design, with an exit pupil that's not too large or too small. Maybe 4-5mm. Anything larger will be too heavy to one-hand and keep steady, especially for a 73 YOW.
When shopping, turn a potential buy around and point it up at a bright overhead light some distance away, so you're looking through them backwards. What you're looking for is a smooth, round circle. If instead you see a hexagon,count that as a mark against it.
Hold it at your stomach and reflect an overhead light off the objective end and note the color and quantity of reflections. Any white reflections indicate not all glass surfaces have anti-reflection coatings.
Higher Q binos will have prisms made of BAK4 glass. It's a higher grade than common BK7 glass. However with all of the chinese imports, the prisms may not be the higher Q glass even if it says so due to fraud.
The challenge will be finding a bino that meets all of these criteria within your price range.
