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Message: <blockquote data-quote="brocknroller" data-source="post: 3252700" data-attributes="member: 665">UPDATE: I found the quote from Dobler about Zeiss purposely designing the SF with enough pincushion to avoid RB, and also his statement that only 5% see RB (he actually said 5-10%), but you'll note that he doesn't mention about where he gleaned those numbers or that any "Drs" were involved in the study or even that it was a study. I've requested more information about where he got those numbers, so I can forward it to Holger to evaluate.It sorta sounds like the people Zeiss contacted were users who couldn't adapt to RB (and hence, who might buy an SF with more pincushion), rather than those who merely saw RB but adapted, but the wording isn't quite clear. If he did mean that, it might reconcile the difference between Holger's numbers and Dobler's. I hope he will clarify that, too. The comments were from Lee's interview with Dobler, excepted below:Now for our final question. With SF you have tried to achieve a balance between a flat field, large field of view, sharpness up to the edge of the view and minimising the well-known effect called ‘rolling ball’. How successful have you been with these four desirable attributes?We found a good balance between these different things and especially in the control of the so-called rolling ball or globus effect that affects between 5 and 10% of people. We contacted some of these people and asked them to try different binoculars having different levels of field-flattening and we came up with a value that gave the best balance between field flatness and control of the globus effect. This means SF is not quite so flat-field at the very edge but it is nearly so, and from what those people told us almost everybody should be able to enjoy SF without noticing any globus effect.</blockquote>

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