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05-31-2012, 06:17 AM   #136
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Put theory and measurement up against empirical observation, and guess who wins every time?

05-31-2012, 08:10 AM   #137
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QuoteOriginally posted by Designosophy Quote
Put theory and measurement up against empirical observation, and guess who wins every time?
Huh? I think I get what you're saying, but it's a bit confusing... because "empirical observation" is the same thing as "measurement".

Last edited by ElJamoquio; 05-31-2012 at 10:21 AM.
05-31-2012, 10:01 AM   #138
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QuoteOriginally posted by ElJamoquio Quote
Huh? I think I get what your saying, but it's a bit confusing... because "empirical observation" is the same thing as "measurement".
You're right. Let me see if I can rephrase:

Observed photographic results trump results assumed by deduction from measurements. This is much in the same way that observing a bumblebee fly trumps the assumption that it cannot fly based on wing measurements and theories of how flight works. (Yes, I know that bumblebee flight is understood now, but it wasn't always.)
06-01-2012, 05:22 AM   #139
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QuoteOriginally posted by Blue Quote
Actually, he started out with the M 40/2.8 design but reworked the elements, especially the rear element.
Interesting. Do you remember where you have read about this?

06-01-2012, 05:49 AM   #140
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QuoteOriginally posted by Designosophy Quote
You're right. Let me see if I can rephrase:

Observed photographic results trump results assumed by deduction from measurements. This is much in the same way that observing a bumblebee fly trumps the assumption that it cannot fly based on wing measurements and theories of how flight works. (Yes, I know that bumblebee flight is understood now, but it wasn't always.)
Empircal observation also lead people to believe the world was flat.
06-01-2012, 07:12 AM   #141
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QuoteOriginally posted by Asha Quote
Empircal observation also lead people to believe the world was flat.
Empirical observation allowed people to believe the earth was round, too, though...

...so which level of empirical observation is taking a picture? I think I'm in the second camp.
06-01-2012, 07:41 AM   #142
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QuoteOriginally posted by Asha Quote
Empircal observation also lead people to believe the world was flat.
People have believed that the earth was round, at least since the times of Plato and Aristotle. Perhaps the "common people" didn't, but the educated people were generally of a different opinion.

When Columbus wanted to "sail west to go east," the issue that the educated people had, was not that they thought he would sail off the end of the eart, it was that they thought it was much to far to sail for the vessels of that day. And they were right. If North and South America weren't here, it would have been much too far. Columbus thought that the distance from the Canary Islands to Japan was 2300 miles, while it is more like 12,000 miles. He was wrong, but then again, even blind squirrels find acorns occasionally.
06-01-2012, 07:55 AM   #143
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...and empirical observation of ships disappearing over the horizon was one of the first clues to the curvature of the earth.

06-02-2012, 07:52 PM   #144
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QuoteOriginally posted by Class A Quote
Interesting. Do you remember where you have read about this?
I have been out of the country for a week (actually was when I made that post.) and had limited access to the net. While the formula and layout are the same, look at the front and rear elements as well as the others. Plus, the LTD has the Ghostless Coatings on that rear element. Somewhere the designer stated in an interview that the DA LTD was a different lens optically, but I can't find it right now.

M 40/2.8 Pancake





DA 40mm LTD



Special Features: aspherical element(s), ghostless coating



M 40/2.8

DA 40/2.8 AL Limited
06-03-2012, 12:32 AM   #145
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QuoteOriginally posted by Blue Quote
While the formula and layout are the same, look at the front and rear elements as well as the others. Plus, the LTD has the Ghostless Coatings on that rear element. Somewhere the designer stated in an interview that the DA LTD was a different lens optically, but I can't find it right now.
Thanks!
I'm always interested in background information to optical designs, so that's why I asked about the source, but I understand that it is sometimes difficult to find a certain interview or text again.
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