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02-21-2009, 08:15 PM   #1
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"This Lens Is Soft" and Other Myths?

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Interesting read: --> This Lens Is Soft and Other Myths




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02-21-2009, 08:27 PM   #2
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he neglects to mention the K20D also has the lens calibration feature
02-21-2009, 08:37 PM   #3
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QuoteOriginally posted by a a i b Quote
he neglects to mention the K20D also has the lens calibration feature
Yup!

I think he just mentioned off the top of his head what he remembered.

There are some folks in the dpreview Nikon D40-60-80-90 forum forum who think that feature is useless.
02-21-2009, 08:40 PM   #4
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They must get a lot of complaints. And they don't rent Pentax.

02-21-2009, 08:43 PM   #5
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QuoteOriginally posted by jsherman999 Quote
There are some folks in the dpreview Nikon D40-60-80-90 forum forum who think that feature is useless.
It would be on a Nikon wouldn't it?
01-18-2010, 10:23 PM   #6
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Sorry, I'm digging up an old thread again... but I thought this deserved comment.

What the author states rings true with something I've been investigating the past 1/2 year. AF systems are just not that accurate, and this inaccuracy gets exposed by the faster lenses. What was adequate in the film days, is now beginning to show its limitations with higher-res sensors and instant review. Not sure how easy this is to solve, but it may involve a total redesign of the entire AF loop, from body to lens, and back.
01-18-2010, 10:34 PM   #7
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QuoteOriginally posted by photogerald Quote
Sorry, I'm digging up an old thread again... but I thought this deserved comment.

What the author states rings true with something I've been investigating the past 1/2 year. AF systems are just not that accurate, and this inaccuracy gets exposed by the faster lenses. What was adequate in the film days, is now beginning to show its limitations with higher-res sensors and instant review. Not sure how easy this is to solve, but it may involve a total redesign of the entire AF loop, from body to lens, and back.
Definitely, a lens does not "front-focus" or "back-focus". The combination of the camera phase detection AF system, lens and subject/light causes this. Lenses have a tint as well as chromatic and spherical aberration that affect focusing, but in the end it's the AF system that decides when to stop hunting and adjusting.
01-18-2010, 10:51 PM   #8
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Yes, this article was posted here 6 or 8 months back by another forum member. It is good to see it posted again, because we all need to absorb its message. I think it makes sense, explaining the soft-lens issues of which we hear so much. This is just another example of how makers of things have virtually eliminated their Quality Control department, thereby putting the burden of QC on the consumer. Thanks Jay!

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