What is the relationships here? I'm pushing 59 and of course have noticed my vision decline somewhat. Distance is still good but I do need reading glasses. I also have a lot of floaters in my eyes maybe from spending so many years scrounging around with a pack in high desert sun. (I really have)
Anyway in learning about bins I think I remember reading recently that often a 32mm aperture will gather as much light as to an old eye as a 42mm. Based on this but without confirmation I started looking at the 32mm's with renewed interest. In comparing my Monarch 3 8x42 with my Eagle Ranger RST 6x32 I was impressed by the brightness and clarity of the 6x. They were brighter and sharper IMO even at close distances. I ended up wondering how much the FOV had to do with this because the 6x has almost 80 more ft.-1000.
Has anyone looked into this in relation to optical choices? I'd like to know more about this.
BC,
You mentioned objective diameter, age and eyes but I think it has more to do with exit pupil rather than just objective diameter. Our eyes don't dilate as much in low light conditions as we get older. During regular daylight hours our eyes dilate to a measurement below the level of what most typical full and midsized binoculars provide which is why an 8x32 binocular (with an exit pupil of 4 mm) seems just as bright as an 8x42 binocular (with an exit pupil of 5.1).
I can think of two reasons why a 6x model might seem "clearer" and sharper than a comparable 8x model. One, as you decrease in magnification it becomes much easier to hold a steady image...assuming the 6x binoculars aren't significantly lighter in physical weight. Two, at any given price point, as you go down in magnification it is more difficult to notice any optical deficiencies in the unit. So, if there is an issue with spherical aberration, chromatic aberration, etc... in the design then it is less likely to be noticeable in a 6x model in comparison to an 8x or 10x.
[quote=black crow;2333641]
Has anyone looked into this in relation to optical choices? I'd like to know more about this.[/quote]
http://www.birdwatching.com/optics/...5_agingeye.html
Jim