Encounters with Zeiss 8x42 HT and SF (1 Viewer)

[henry link]

...could Zeiss really get similar edge performance with pincushion in a field that wide... and if yes, why on earth didn´t they do it.

That's a good question Tobias. One that Zeiss (and Swarovski) would need to answer. My guess is that there is currently no consensus among binocular designers as to which distortion profile is best. Mustache distortion may look attractive because it seems to offer some of the benefit of traditional pincushion combined with something close to straight lines near the field edge. Perhaps the visual disturbance it may cause some people when panning just hasn't been studied.

Henry

 

[ronh]

Kimmo,

Thank you for your reports, nicely done and interesting. Your two eyed unboosted method has the great advantage of realism. I think a lot of off axis viewing depends on eye position, and it's impossible to get that with a one eyed view. Although I am not convinced your unboosted central resolutions are much more than a demonstration of enviable eyesight, the off axis resolutions are ideal.

I wish Canon made a lightweight, unstabilized model with the same optics, that didn't look like a Klingon attack ship, for us traditionalists. I also wish somebody else would get off their butts and make a stabilized binocular--what in the world is taking them so long?

Ron

 

[kabsetz]

Ron,

Thanks for your nice words. I have indeed tried a bunch of different ways of checking off-axis performance, and what I used here is what I think of as the least compromised easily performed test. It gives a reasonable approximation of real-life use conditions since I don't peek around to the edges in unnatural ways. And, if I don't use a resolution target and have the binoculars on a tripod at a fixed distance and don't carefully measure the distance from center of field to point being evaluated, any estimation of sharpness or unsharpness becomes so imprecise as to be essentially a meaningless opinion.

The unboosted central resolution is needed as a reference, to show where measurable degradation starts off-axis and how much the additional aberrations that progressively come to play off-axis negatively influence the amount of fine detail that can be seen.

For more or less accurately detecting differences in unboosted central resolution, I need to vary the distance to the target since the steps in the USAF 1951 target (or any other target I know of) are too coarse for giving meaningful results. That kind of a precision level requires too much work when testing off-axis performance.

I'm aware of the objections against the relevance of unboosted visual central resolution measurements in general, and agree that they do constitute a test of the visual acuity of the tester first and foremost. However, I still stand behind my earlier assertion that I get better unboosted results visually with binoculars or telescopes that give better boosted readings even when the boosted resolution is much higher than what I get in the unboosted test. This means that although my unboosted test results do not show the true instrument resolution, for me they do show meaningful differences between instruments, i.e. they seem to accurately reflect the compound instrument+eye+brain performance.

For your sake, and for other people who would prefer light weight over IS, I agree it would be nice if Canon would make a luddite version of their 10x42. For myself, although I'd be among the first to buy an updated model of the current 10x42 L IS (providing it addressed at least some of the issues with the current model), I know for certain that I'll never again shell out significant amounts of money for an unstabilized binocular.

As for your last point, it would certainly be most welcome for some serious competition to emerge so that we'd either have better alternatives or Canon would be forced to gear up their R&D on these things. It seems, though, that it is not easy to do.

Kimmo