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05-31-2011, 02:19 PM   #331
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QuoteOriginally posted by jstevewhite Quote
Actually that sequence goes a long way towards moving me more to the "pd" side, as in "a visible but difficult to explain quality of a lens' rendering", not as in "something about a lens that makes all its pictures look better" (lol). I picked out the images from the 43, as well. Good stuff, great information for a skeptic like me.
QuoteOriginally posted by Todd Adamson Quote
So, while rational arguments for even the possibility of pixie dust find your skeptic's armor impervious, the simple gut reaction to a few images gets you to budge a little. I'm not sure if this is poetry or irony.
Mr. White, you have apparently frustrated Todd to the point of pulling his hair out.

05-31-2011, 02:27 PM   #332
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QuoteOriginally posted by asdf Quote
I'm beginning to think pixie dust means "exif data". I hope I removed it from the two images below.
So which of the two images below (copyright photozone.de) looks better to your brain and why? One of them reminds me of a mirror lens...

.
I'm calling poor choice of subject for demonstrating image quality in both cases. Too busy, harsh light, verging on overexposure, and probably camera shake from not being shot on a tripod.

The first one has more personality for sure, but not necessarily in a good way. Second is just dull.
05-31-2011, 02:28 PM   #333
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QuoteOriginally posted by asdf Quote
I'm beginning to think pixie dust means "exif data". I hope I removed it from the two images below.

.

So which of the two images below (copyright photozone.de) looks better to your brain and why? One of them reminds me of a mirror lens...

.
The second one looks better: cleaner bokeh in the very busy background, and wider depth of field with a higher degree of peak sharpness on the subject.

The first photo is unmistakably displaying the harsh ring bokeh of the FA43, which is extremely recognizable in situations like this. I'm assuming the other lens is the DA40 then? I see what you're going for, but they're both crappy snapshots without the slightest hope of pixie dust. So, when taking this kind of poorly composed snapshot, the DA40 might produce slightly less terrible results?
05-31-2011, 02:35 PM - 1 Like   #334
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QuoteOriginally posted by v5planet Quote
I see what you're going for, but they're both crappy snapshots without the slightest hope of pixie dust.
Pixie dust is the aikido of optics: it's not terribly useful or meaningful and you need both parties to play along.

05-31-2011, 02:37 PM - 1 Like   #335
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QuoteOriginally posted by asdf Quote
Pixie dust is the aikido of optics: it's not terribly useful or meaningful and you need both parties to play along.
I see someone has given little thought to the principles and applications of 合気道.
05-31-2011, 02:48 PM   #336
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QuoteOriginally posted by v5planet Quote
I see someone has given little thought to the principles and applications of 合気道.
Maybe, not. However, I did give some thought to the "moving the goalposts" fallacy and "folie a plusieurs."

...while we're on the subject of bokeh, I noticed that TOUGEFC posted an image that has a mirror lens like quality and noticeable vignetting, as well:



If "pixie dust" is synonymous with less than stellar optical qualities, then at least we've got it pinned down somehow.
05-31-2011, 02:52 PM   #337
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QuoteOriginally posted by Todd Adamson Quote
So, while rational arguments for even the possibility of pixie dust find your skeptic's armor impervious, the simple gut reaction to a few images gets you to budge a little. I'm not sure if this is poetry or irony.
Oh, not at all. It's that it was a simple blind trial: "Pick the images with 3d". I picked 'em; they turned out to be the 43. And it didn't convince me, per se; just another tick in the "pro" category

I'll get my own 43 here in a few days, I think. I'll report back then. I'm not afraid to be wrong, as long as it was for the right reasons! >8]
05-31-2011, 02:55 PM   #338
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QuoteOriginally posted by jstevewhite Quote
Oh, not at all. It's that it was a simple blind trial: "Pick the images with 3d". I picked 'em; they turned out to be the 43. And it didn't convince me, per se; just another tick in the "pro" category
Unless the experiment is double blind, it shouldn't convince you of anything.

05-31-2011, 03:05 PM   #339
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I once did a blind study:

05-31-2011, 03:06 PM - 1 Like   #340
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QuoteOriginally posted by Todd Adamson Quote
I once did a blind study:
Yes, but that's obviously a single-blind.
05-31-2011, 03:09 PM   #341
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QuoteOriginally posted by DogLover Quote
Mr. White, you have apparently frustrated Todd to the point of pulling his hair out.
Happy to be of service.

I know my particular ... approach ... can be extremely frustrating to some people. I don't necessarily argue my opinions; I try to reason my way through things and form my opinions based on that, not the other way 'round. I've been taking pictures a long time, and I *want* to believe in pixie dust... I want to believe, as they say. But in the end, I think like a scientist, and a blind test is the coin of the realm

But ... In my life I've exposed exactly 25 sheets of 8x10 film with an old Goerz Dagor and a Kodak Ektar. Note that I had learned B&W developing already, and the rudiments of the zone system, and had my own darkroom in my basement. Anyway, I went in halves on a 50-sheet box of 8x10 tri-x with a friend.

Initially, the first, say, five, ten exposures, I was slack-jawed in astonishment. If you've ever seen an 8x10 contact print, exposed and processed properly, you'll know what I mean. The tonal range and richness - and yes, sharpness - is absolutely phenomenal. It made everything beautiful. I thought.

But by the tenth or eleventh sheet, I realized that wasn't enough to make a great photograph. The wagon wheel image? It was just a wagon wheel, and a fairly pedestrian one at that. It was properly exposed and focused and even a reasonable composition, stunningly sharp, but it never rose above... "run of the mill"? as an image.

So I think there is no technical thing that will make a pedestrian image into a good one, nor a good one into a great one. The technical foibles of the equipment are like paint brushes, and the artist must choose them appropriately. If one agrees, then Marc's point about objective qualities vs aesthetics is water-tight.
05-31-2011, 03:11 PM   #342
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QuoteOriginally posted by DogLover Quote
Yes, but that's obviously a single-blind.
05-31-2011, 03:12 PM   #343
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The FA 43 was designed as a "normal" lens and was bokeh was not its top priority. It should not be surprising, therefore, that they opted to create a lens which sacrifices smooth bokeh for extreme sharpness. I don't quite understand why they went in the totally opposite direction with the FA 50, but it's clear to be which of these two is sharper, and which one has the better bokeh (and how no lens will be the best of both worlds).

You will notice they did the *exact opposite* for the FA 77, which is not the sharpest, but has very pleasing bokeh (it's application as a portrait lens demands this compromise).
05-31-2011, 03:14 PM   #344
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QuoteOriginally posted by asdf Quote
Unless the experiment is double blind, it shouldn't convince you of anything.
So the photographer can't know what lens he's using? Executing a proper double blind in this case is well beyond the scope of the forum, I think. It would be like... YOU shoot a bunch of images with a pd lens and a non-pd lens. Then write numbers on them randomly, and record in a book which was pd and which was not, then send 'em to me. Then *I* post 'em on the web in a forum that you can't see, but everyone else can, and ask opinions, tabulate them, and return them to you, where you compare them to your book and do analysis. Do-able, but a PITA.

Many things, incidentally, cannot be double-blinded. Just sayin'.
05-31-2011, 03:16 PM   #345
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QuoteOriginally posted by asdf Quote
Maybe, not. However, I did give some thought to the "moving the goalposts" fallacy and "folie a plusieurs."

...while we're on the subject of bokeh, I noticed that TOUGEFC posted an image that has a mirror lens like quality and noticeable vignetting, as well:



If "pixie dust" is synonymous with less than stellar optical qualities, then at least we've got it pinned down somehow.
I'm not sure whether your first comment was directed at pixie dust or at aikido, but I would take less offense at the former, since it is an aesthetic notion rather than a practical one. Curious to know what your background in aikido is since you are so dismissive of both its efficacy and value to its practitioners.

As for Simon's image -- I agree, the bokeh in it is a bit distracting, and the 43 is clearly best used without a busy background. Regarding the vignetting, I'd be curious to know if it was added in PP or if it was present from GO. Sometimes people enjoy adding those to strengthen their images
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