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I used a borrowed pair of the Vixen ultra-wide binos at Astrofest. In a dark sky, they gave me at most 2 magnitudes advantage over naked eye, commensurate with 10-15mm binoculars. Looking at the three stars 10' from the SCP, I could easily see the mag 6.8. Barely see the 7.8 and not see the 8.7 mag star. As I've aged, my pupils now only dilate to about 5.5mm last time I measured them about a year ago. A teenager with 7mm dilation could do about one magnitude better.
The big aperture on wide binos is used to drag in the wide field of view. Look backwards through a regular pair of binoculars and you'll see a similar effect but you are never using more than a small aperture. The older your eyes are, the smaller your dilation, the smaller the effective aperture.
For star hopping, you will do better with a pair of standard binoculars and a narrower 6 deg field as the standard binos will let you see stars that are:-
35mm - about 4 mags fainter than naked eye mag 9-10 in a dark sky
50mm - about 5 mags fainter than naked eye mag 10-11 in a dark sky
I have based the above mag estimates on average middle age vision limits of naked eye mag 5-6 in dark skies.
So it's really a question of what you need, a wide field with fewer hop stars, or a narrower field and many more hoppers.
In my experience, it's pretty easy to point, centre, and view anything in a 6-degree binocular or finderscope field.
Joe
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