Cameras and Lenses
Ideal focusing?
Hi all,
Focusing speed is one of the most significant ergonomical features of the binoculars. A user may love the optics, but may not be able to adapt to overly fast or slow focusing (and vice versa - of course). I seem to remember someone presenting an idea of dual focuser binoculars with two focusing wheels like in the Leica and Zeiss spotting scopes.
A free idea for binocular developers: a single wheel with dual speeds. (Not sure I can explain this properly...)
Generally a fast gearing for rapid focusing, but with a narrow sector (20-40°) of "play" containing maybe 1:4 slower gearing. In practice the current focus position would carry along the fine (slow) focus region. You would first overfocus slightly and then return to this "fine focus" sector. You would not have to hunt back and forward, but when necessary it would be easy to get back to high-gearing region. The slow gearing would be always where you need it, but at the same time the total rotation range could be small.
I understand that it would slightly add complexity of the focus transmission, but I doubt it would become as complex as the mechanism successfully used used in the Swaro EL's.
Did I confuse everybody? Comments? 
Ilkka
[QUOTE=iporali]Hi all,
Focusing speed is one of the most significant ergonomical features of the binoculars. A user may love the optics, but may not be able to adapt to overly fast or slow focusing (and vice versa - of course). I seem to remember someone presenting an idea of dual focuser binoculars with two focusing wheels like in the Leica and Zeiss spotting scopes.
A free idea for binocular developers: a single wheel with dual speeds. (Not sure I can explain this properly...)
Generally a fast gearing for rapid focusing, but with a narrow sector (20-40°) of "play" containing maybe 1:4 slower gearing. In practice the current focus position would carry along the fine (slow) focus region. You would first overfocus slightly and then return to this "fine focus" sector. You would not have to hunt back and forward, but when necessary it would be easy to get back to high-gearing region. The slow gearing would be always where you need it, but at the same time the total rotation range could be small.
I understand that it would slightly add complexity of the focus transmission, but I doubt it would become as complex as the mechanism successfully used used in the Swaro EL's.
Did I confuse everybody? Comments?
Ilkka[/QUOTE]
Ilkka,
A good bin doesn't require a lot of focusing. Both my Leica 7X42 and Nikon SE 8X32 dial directly in to a near-perfect focus about 90% of the time and it's one of the MAJOR reasons I chose them. I sometimes tap the SE focus wheel to get THE PERFECT image and the Leica might require a nudge now and then to obtain the finest view.
I remember reading about a study that concluded excessive fine focusing QUICKLY ruined an image because it strained the user's eyes. The recommendation was to focus, wait a moment for your eyes to adapt, apply a quick final adjustment, and then leave the focuser alone. If this method does not work 99% of the time, I argue the optics aren't high quality to begin with and no amount of focusing will satisfy.
John
Personally I don't see any need for this kind of feature. Focusing my 10x Classics or Ultravids is ocassionally necessary during normal viewing. After a few months of regular use, my finger movements to adjust to what I'm viewing become second nature... almost subconcious.