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 Re: How much of an X-Pro2 optical VF is blocked by the Voigt 23mm Nokton? | |
gdanmitchell wrote:
DOF charts and calculators generally are based on some assumptions about how good is good enough that were developed quite a while ago, way back in the film era. Standards for “sharp enough” were pretty different then — we rarealy maginified the original image to the extent that we do with digital today, and it was actually no common to print larger than 8x10 or maybe 11X14 from 35mm film.
Dan, this isn't really directed just at you - but at everyone else who's saying that "acceptable" sharpness is a subjective choice by the photographer and depends on the use case (artistic intent, print size, viewing distance, etc.). That is obviously true, and we all (hopefully) agree on that. I think for this, we're talking across each other. Those of us who have owned this lens in question, the Voigtlander 23mm F1.2 or other early Voigtlander X mount lenses, are focused on the error with this lens.
Again, there is an error here -- at F4, the lens barrel markings, and the LCD zone it shows in "film basis", the DoF it shows is correct for F16 - F22, not F4.
If the standard used is appropriate for holding a 8x10 inch print at some distance, this lens shows a DoF appropriate for holding a wallet sized photo at the same distance.
The error here is a magnitude of 4x-5x in the WRONG direction (i.e., too lenient, instead of a "pixel" 100% zoom basis, it's in a "blob" 20% zoom out basis).
I think it's fun to talk on the internet about whether or not the standard 1/1500 DoF scale printed on lenses or in cameras are useful or not to us in our personal work.
But that's a separate thing from when some people are focused on warning others (OP) to not buy a lens because this "feature" is defective in this specific lens.
Again, this error is in the early Voigtlander X-mount manual focus lenses and they corrected it in latter ones.
Comments on the subjectivity of DoF choice are moving the conversation off topic as OP, who is clearly an old-school M mount rangefinder shooter is trying to replicate his 35mm rangefinder experience on his X-Pro 2. Which this lens, the VX 23mm F1.2 does poorly due to overly short focus throw (due to keeping the same throw despite the increased minimum focus distance) and zone designations on the lens barrel (which are simply erroneous).
This lens held the promise of a M mount-like experience, which included zone-focusing for many of us, but failed to deliver in many respects.
When I purchased and discovered this error myself 5 months ago, I googled the issue and found other threads where there was discussion on this topic, and saw it devolved into debates about the subjectivity of DoF and CoC choices. That's all fine and good. But the information that there is an error with this lens was drowned out. In part, I think, because no one had done the math (e.g., that at F4 it showed a DoF appropriate for F16-F22.)
The math, I think makes the point clear. We're not talking about the subjective decision here.
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