A few observations:
Stores: I purchased my Fujinon 14 x 40 Techno Stabi from a large optics store where I could take all of their stabilized binoculsars out of doors, and had a long range to look at both moving and non moving objects—I could see how they felt, how good the stabalization was, edge to edge sharpness, chromic aberrations etc.
I choose the Fujinon glasses—but most of my good camera lenses are stabilized Canon. I went in thinking I was going to buy Canon. Go try all of the binoculars which are available—but don’t go to K Mart or Wal-Mart—go to a good sporting goods or optics store.
Same as I buy my camera lenses—I go to the local store, take my camera body, and try on the lens I want to buy out of doors, look at the photos on a computer, and see if that is really what I want.
Environment: I have two classes which have traveled over 100,000 miles at sea—high temp, high humidity, cold, salt spray etc. They are going to have a much harder life than glasses which stay in a nearly constant environment—humidity low, tmeps stable etc. Looking at 6 glasses I have in the room now—two are like new-they are the ones with 100,000 miles. They are NITROGEN filled, the coatings are still perfect, no scratches, bodies are free of corrosion. Why? They were taken care of, and of good quality.
I have several others which have fungus on the internal optics, have loose fitting center focus, leak air when you focus them (and draw in fungal spores and dust),
The bodies have corrosion, and the focus mechanism is loose—if you put pressure on one eye piece over the other, it may put the glass out of focus.
Lens cleaning: Air—bulb—not canned or compressor. Camel hair brush (don’t touch the bristles with your fingers, since it leaves oil on them. You can use special lens tissues, or a Lens pen—but when using cleaning fluid—put it on the special tissue or micro fiber, not on the lens!
Exit pupil: Both the objective (the optic toward the way you are looking) and the exit pupil (aperture where the light comes to your eye). Although the amount our pupil will generally not dilate as you age—There are plenty of 70 year olds who still have a maximal pupil diameter (iris of the eye diameter) which can be 7 mm when in the dark . I can definitely notice the difference between 7 x 30 and 7 x 50 glass when looking at low lights.
Fujinon high end stabilized binocs: There are two—the Techno Stabi 14 x 40 somewhere in the $ 1200 range. Then there is the $5,600 Fujinon Stabiscope Gyro stabilized 16 x 40.!
I have not found that battery usage in the Fujinon batteries is an issue. They last a long time. I take them out when the binocs are not being used.. The binocs live in a water proof Pelican Case—the Batteries will last several years of use—depending on how you use the binoculars.
