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Message: <blockquote data-quote="kabsetz" data-source="post: 2855923" data-attributes="member: 10167">Cluster,I think your explanation is good and clear. As far as I know, there is no proper term for this. Obviously, from the point of view of binocular manufacturers, this should not happen in the first place so why would they have a term for it? We could maybe come up with a term, such as lack of focus synchronicity, or asynchronous focus, but any new term would need an explanation about as long as yours.The same problem is pretty common in cheaper CF porroprism binoculars, where the eyepiece bridge moves in and out while focusing. The bridge can rock left to right and cause rather pronounced diopter imbalance depending on how you lean it against your face, and one or the other eyepiece tube typically has more friction than the other so lags behind when focusing.John,I'm with you on this. It is much better to have uneven focus resistance than to risk asynchronous focus or barrel slop. It is not only Swarovski that uses this spring loading technique, though. The new Zeiss Victory HT's have it too, but since their focus wheel is bigger people don't seem to notice it as with a larger wheel diameter your finger exerts more torque when focusing.Kimmo</blockquote>