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Meopta 'Extra Lens'
This was my "aha" moment. It looks like certain brands cannot be said to have any field depth, therefore. But learning from it, I realize, what standards that are used here are for extremely sharp focus "in the range". This is called trying to measure at the top of the plateau. As you... -
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Meopta 'Extra Lens'
I'm sorry. I just lost it. I was measuring the shoulders on a phase error curve to estimate the plateau. Just habit. The prevailing paradigm here is to attempt to measure on the plateau. You don't need any additional weight on your shoulders with that kind of burden. Please disregard my... -
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Meopta 'Extra Lens'
Since I was responding to patronizing and irrelevent items in the first place, I may be expressing some shock, but it's just my tryiing to cope with your understanding of depth of field and especially of metrology. But to address your "issues": Clearly it is well beyond that necessary to... -
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Meopta 'Extra Lens'
If you are close enough it falls off rapidly and you don't need to worry about the little differences. This is the debating technique called "radical skepticism". One side is haggled for the last iota of detail and this distracts from a lack of the evidence from the other. Or...wait: maybe... -
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Meopta 'Extra Lens'
Suffice it to say that at 15 feet, ALL binoculars had more than enough resolution to focus at 10-pt font, and the fuzzing at 22-pt font is probably many dozens of resolution limits beyond any limits of the system. In a nutshell, worries about each binocular's absolute resolution are orders of... -
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Meopta 'Extra Lens'
I have proposed an experient back on the "dioptre adjustment" thread that almost anyone can perform. A CONTROLLED experiment. Simple. No hemming and hawing about different days and objects. If the brightness has some effect, this is far more potent. If brightness has effects, they are AGAINST... -
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Meopta 'Extra Lens'
And not the same-power with different-objective, different-depth results I observed over and over? With binoculars? Not the same binoculars with a smaller aperature and far deeper field...observed?? Well, at least I won't suffer Galileo's troubles. This has been quite an education, in more... -
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Meopta 'Extra Lens'
I believe you have the sense of my thoughts wrong. I actually pushed back against a simplistic camera-oriented view in one case. I do not believe the two are the same. I do believe they both have considerably more variability in their parameters than some people do, or understand. An optical... -
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Meopta 'Extra Lens'
Magnification is based on one object at a specific distance and in focus. The question is: how do things de-focus as they move off that point? The fact that you can have different behaviors in that regard is actually put to use in many fields. The world is not one lens facing one lens. At... -
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Meopta 'Extra Lens'
If that were absolutely true, either it would have zero effect, or you would have to move them both the same amount to preserve the veracity of that statement. You either have 'is part of the objective' or you have 'alters the focal point of the objective a lot'. You can't have both. As... -
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Meopta 'Extra Lens'
Heh...cool gadget. Given their sharpness, it could work. -
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Meopta 'Extra Lens'
Yes, I think that's it. The focusing element is forward, instead of moving the ocular. I got to visit an optical engineer and do some ray tracing. Moving a field/focuser behind the objective has a very potent effect on the focal point (so it makes for easy smooth focusing). It also... -
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Meopta 'Extra Lens'
The lens in question looks very much like the mid-body focuser/field lens on my Swift spotting scope. It is chromatically compensated (which doesn't take much in that position) by other elements, front or back depending on position.