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Author Topic: CS3 and PhotoKit Sharpen?  (Read 22339 times)
Stephen Best
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« Reply #40 on: December 28, 2006, 02:41:23 PM »
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I've had some of my writing appropriated. An article I did (in 2002 on Color to B&W conversions) was, well, let's just call it "appropriated". I quoted Thomas Knoll as telling me that Photoshop's default grayscale conversion was 30% Red, 60% Green and 10% blue channel calculations and went on to explain how to use channels to make custom B&W conversions...in his 2003 article "Split Your Channels for Improved B&W", he writes those exact same numbers...30, 60 10. He doesn't reference my article and I happen to know for a fact that Photoshop's default conversion %'s is -NOT- documented anywhere...I got it from the horse's mouth-Thomas Knoll. But he writes it as though -HE- discovered those numbers all by himself (ya see, numbers CAN be valuable :~)
[a href=\"index.php?act=findpost&pid=92660\"][{POST_SNAPBACK}][/a]

These numbers (actually 30, 59, 11) were well known ages ago. I used them myself in a product over a decade ago. As also was the practice of multipass sharpening. I remember a conversation with the guy I bought my Imacon scanner from advocating such a technique. All this was well before PixelGenius was even thought of. Anyway, I'm sure you're familiar with Newton's metaphor "standing on the shoulders of giants", apparently also borrowed from Bernard of Chartres from much earlier.
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« Reply #41 on: December 28, 2006, 04:01:15 PM »
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These numbers (actually 30, 59, 11) were well known ages ago. I used them myself in a product over a decade ago.[a href=\"index.php?act=findpost&pid=92669\"][{POST_SNAPBACK}][/a]

Well. . .the ACTUAL numbers are fractions, not whole numbers-and Thomas told me what the numbers were for Photoshop 5 alpha which would have been about 1997. I was referring to my article, published in 2002 and referring to Mitch's article published in 2003 which he uses the EXACT same "rounded" numbers (I had rounded the %'s). So, where did Mitch get his numbers? He doesn't say...

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As also was the practice of multipass sharpening. I remember a conversation with the guy I bought my Imacon scanner from advocating such a technique.

Yep...Bruce wrote about multi-pass sharpening for his Real World Photoshop 3 book-the first time that I can recall -ANYBODY- breaking from the pack that said to "sharpen only at the end". It was on pages 237-256, published in 1996 (although it was written in 1995-and yes, I have the book in front of me if you wish me to cite the passages...). In it Bruce also identified the practice of achieving a sharpening halo of between 1/50 - 1/100 of an inch for output sharpening-another thing Mitch has failed to credit to Bruce.

And, Bruce consulted with Imacon and advocated only light sharpening if any, in the scanner-or turning sharpening OFF (remember the controversy about having to plug in a MINUS sharpening setting to actually turn it off? That was Bruce and Andrew who discovered that and I was also involved with Imacon at that time) and additional sharpening after in Photoshop. So, that's where -YOUR- guy got it from.

You all can try to claim that this stuff is old and known. . .yes, it is. And almost ALL of it derived from Bruce's own research and writings from so long ago, nobody remembers it was Bruce who first wrote it. That's what makes some "johnny-come-lately" like Glenn E. Mitchell II Ph.D who regurgitates the work of others, so galling...

I've been doing this stuff since late 1991 (a LONG time ago in computer/software years) and I've known all the major players (authors, engineers and experts) for years. I know EXACTLY who wrote what and when...all the major authors and experts are -VERY- careful about giving respect and credit where credit is due...Mitch? Not so much...

Look folks. . .you -ALL- owe a very serious debt of gratitude to the work of Bruce Fraser...unless you known for a FACT that somebody else first wrote or advocated something, you would do yourselves a favor and pretty much assume that Bruce, or some of the other early authors such as Biedny , Deke, Monroy, Russell Brown, Blatner, Eismann DID originate the concepts and principles...

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Anyway, I'm sure you're familiar with Newton's metaphor "standing on the shoulders of giants"

Yep. . .and it's nice when you can keep their names straight, huh?

Now, ya wanna keep quibbling?
« Last Edit: December 28, 2006, 04:13:06 PM by Schewe » Logged
digitaldog
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« Reply #42 on: December 28, 2006, 05:04:52 PM »
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A post of Bruce's (notice the date):

•---- COMPUSERVE #1, 7/19/93, 7:17:22 PM, Adobe Forum ----•
¶FB¶MF
Message: #78248, S/16  Photoshop
Date:    Mon, Jul 19, 1993 5:15:04 PM
Subject: #78128-"Usual" UnshMsk Settings
From:    Bruce Fraser [MacWEEK] 72511,131
To:      Kelvin Olson 75140,726


Kelvin,

The reason there are no defaults for USM is that you really need to use different settings for different images, and even for the same image at different resolutions. It's complicated.

USM is essentially a contrast function. Suppose you have an edge in the image. A plot of the pixel values might look something like this:


What USM does is to boost the contrast around the edges to make it more like:

The Amount setting is f
« Last Edit: December 28, 2006, 05:06:09 PM by digitaldog » Logged

Andrew Rodney
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« Reply #43 on: December 28, 2006, 05:08:48 PM »
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Something about Andrew's post clipped off the ending...
--------------------

The Amount setting is fairly self-explanatory. The pixel radius setting deals with width of the "bump" that exaggerates the edges. The threshold setting is primarily for avoiding the introduction of noise where there's a small contrast difference between adjacent pixels that doesn't represent an edge.

There aren't any canned settings for USM that will mimic Sharpen and Sharpen More: you'll just have to experiment. You can try either copying a small portion of the image into a new document and trying different settings, or just work with a small selection: in either case, do the USM then hit Undo, until you find something you like.

Oh yes, one other thing: final output size also has an impact on USM -- an image being reproduced small will probably require less sharpening than one reproduced at a larger size.

Someone should write something about this, sometime, when they have a spare year...

Bruce
---------------------
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DarkPenguin
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« Reply #44 on: December 28, 2006, 05:33:49 PM »
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So can I take from this the thought that BF's new sharpening book (the one that just got tech book of the year at the online photographer) is definitely worth picking up?
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Schewe
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« Reply #45 on: December 28, 2006, 05:42:52 PM »
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So can I take from this the thought that BF's new sharpening book (the one that just got tech book of the year at the online photographer) is definitely worth picking up?
[a href=\"index.php?act=findpost&pid=92689\"][{POST_SNAPBACK}][/a]

Yep...of course, some might think I'm biased...

:~)
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Stephen Best
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« Reply #46 on: December 28, 2006, 09:01:54 PM »
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Well. . .the ACTUAL numbers are fractions, not whole numbers-and Thomas told me what the numbers were for Photoshop 5 alpha which would have been about 1997. I was referring to my article, published in 2002 and referring to Mitch's article published in 2003 which he uses the EXACT same "rounded" numbers (I had rounded the %'s). So, where did Mitch get his numbers? He doesn't say...
[a href=\"index.php?act=findpost&pid=92675\"][{POST_SNAPBACK}][/a]

Personally, I think you're a bit paranoid and probably overestimate your own contribution in all this. There's been a lot of stuff kicking around, most of which doesn't make it into books, magazine articles or products. The great thing is that we've ALL progressed through the sharing of information, tricks learnt etc.

Anyway, you can keep up this mystique about only PK Sharpener having the secret sauce, but the reality is that there's any number of solutions that will deliver the same or even better results. Now that the more useful techniques and "magic numbers" are in the public domain, thanks to Bruce's openness in his book on Sharpening, it's all fairly moot anyway.
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Ray
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« Reply #47 on: December 28, 2006, 09:02:13 PM »
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Bruce wasn't so much interested in patents...as well as being a Buddhist / vegetarian / Scotsman, he was a borderline socialist (well, at least he was real friggin' liberal) and didn't like the Federal Government so much...but he did value "original intellectual work" and would NEVER take the work of others without scrupulously crediting them. And, while he was real proud of the work he did creating PhotoKit Sharpener (although I did have to teach him how to write actions), he never failed to show people how he did what he did or explain why in seminars and books.
[a href=\"index.php?act=findpost&pid=92664\"][{POST_SNAPBACK}][/a]

It's interesting for people like me (ie, removed from the cutting edge of 'image manipulation' development) to get the inside story. I wasn't aware that Bruce Fraser was a Buddhist. This fact alone strikes some resonance within me. I've been very much influenced by the Buddhist idea that everything we see is essentially an illusion. Such ideas sit comfortably with Western Physics which describes matter as mostly (relatively) empty space.

I remember the occasion well, when I first attended a computer exhibition in the very early 90's, where Photoshop 3 was being demonstrated. Digital photography was very new to me. I knew virtually nothing about it. Didn't even own a computer.

But I knew enough to be able to ask a few questions, one of which was, 'Show me how Photoshop can change the color of a single pixel?' The Photoshop demonstrator proceeded to zoom in to maximum magnification and changed a greenish pixel to a reddish one. He then zoomed out, to fit the full image on the screen (it was probably a low res jpeg) and I could clearly see a tiny speck of red that wasn't there before.

I was truly impressed. Wow!, wow!, wow!. The Buddhists are right?? It's all an illusion.  

Continue with the inside story.
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Schewe
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« Reply #48 on: December 29, 2006, 12:30:50 AM »
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Personally, I think you're a bit paranoid and probably overestimate your own contribution in all this. There's been a lot of stuff kicking around, most of which doesn't make it into books, magazine articles or products.

Uh huh. . .don't have a response regarding Bruce probably being involved with teaching multi-pass sharpening to your Imacon guy, huh?

No, I don't think I overestimate Bruce's contribution to the industry-if anything, due to Bruce's modesty, I think it's vastly understated by many people, including you.

Since you aren't from the US (Australia, right?) I suspect you've never been to a Macworld, a Photoshop Conference or a Photoshop World and seen Bruce speak? You've never seen the crowds hanging on every word and following him wherever he went. You've never experienced his dry whit and unique ability to take a boring, complicated subject and make it fun and easy to understand?

Bruce did go on the road to Australia for GretagMcBeth. . .did you ever get the chance to see him speak? If not, it's your loss...

During Bruce's trip to Australia, he fell in love with Australian wine and bought more than a few cases but had a dickens of a time getting it back to the States...I'm not sure he EVER got all of it.

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Now that the more useful techniques and "magic numbers" are in the public domain, thanks to Bruce's openness in his book on Sharpening, it's all fairly moot anyway.

Well, no, not really...Bruce has been totally open about the "process" but he kept the "magic numbers" pretty close to his vest...do you know the DPI that human vision can resolve for an 8 x 10 print? Bruce did. . .he calculated that for an 8 x 10 print held about 12 inches from your eyes, your vision-assuming normal 20/20 vision-resolved about 355DPI (and this isn't secret, since he wrote about this publicly). 20/20 vision resolves about one minute of one degree arc...one can translate that to actual DPI...But...

Exactly what sharpening numbers do you need to plug into a sharpening routine to provide optimal image sharpness for an 8 x 10 matte print? Or an 8 x 10 glossy print? Don't know? See...it's the numbers to plug into the routine that are important. And, it's those numbers that "Mitch" doesn't grok...he still thinks that "presets" can't be determined and suggests rolling your own.

I'm not saying that other products can't do an excellent job of image sharpening...heck, even Photoshop CS2's Smart Sharpen is a pretty fancy tool and good old USM (written by John Knoll in 1989) can do a swell job. But, since you can't trust the display to tell you how much to sharpen, how are you going to use the display to determine the numbers to plug in?

Since you ain't from around here, I'll give you the benefit of the doubt...but don't doubt Bruce's contribution to this industry both publicly as well as behind the scenes working with Adobe, Apple, Kodak & MSFT as well as the color management companies such as the old GretagMcBeth and X-rite. You do yourself an injustice if you fail to comprehend what Bruce has done and what this industry has lost...
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Stephen Best
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« Reply #49 on: December 29, 2006, 12:56:26 AM »
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No, I don't think I overestimate Bruce's contribution to the industry-if anything, due to Bruce's modesty, I think it's vastly understated by many people, including you.

Exactly what sharpening numbers do you need to plug into a sharpening routine to provide optimal image sharpness for an 8 x 10 matte print? Or an 8 x 10 glossy print? Don't know? See...it's the numbers to plug into the routine that are important. And, it's those numbers that "Mitch" doesn't grok...he still thinks that "presets" can't be determined and suggests rolling your own.
[a href=\"index.php?act=findpost&pid=92731\"][{POST_SNAPBACK}][/a]

I have (had) a lot of respect for Bruce, but it wasn't him who I was talking about.

As for the "magic numbers" for an 8x10, PK Sharpener doesn't currently take the print size into account (nor for that matter the gamma of the working space to generate the Blend If numbers) ... I've done my own tests ... so I'm not sure what you're talking about.
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Schewe
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« Reply #50 on: December 29, 2006, 02:28:34 AM »
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I have (had) a lot of respect for Bruce, but it wasn't him who I was talking about.
[a href=\"index.php?act=findpost&pid=92733\"][{POST_SNAPBACK}][/a]

This thing ain't about me, bud. . .it's about being absolutely, perfectly clear what Bruce meant to all of us. Do you understand that?

And yes, gamma sensitive blends is on the docket for Sharpener 2.0...we already have that tech in PhotoKit Color 2.0.
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bjanes
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« Reply #51 on: December 29, 2006, 08:54:47 AM »
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It's interesting for people like me (ie, removed from the cutting edge of 'image manipulation' development) to get the inside story. I wasn't aware that Bruce Fraser was a Buddhist. This fact alone strikes some resonance within me. I've been very much influenced by the Buddhist idea that everything we see is essentially an illusion. Such ideas sit comfortably with Western Physics which describes matter as mostly (relatively) empty space.

I was truly impressed. Wow!, wow!, wow!. The Buddhists are right?? It's all an illusion.   
[{POST_SNAPBACK}][/a]

The concept that much of our existence might be an illusion is not unique to eastern thought and [a href=\"http://en.wikipedia.org/wiki/Allegory_of_the_cave]Aristotle's[/url] allegory of the cave presents a similar concept. But remember that an illusion is a disordered perception, and there still must be someone around to have that perception, and the ultimate nature of our existence remains unexplained. Cogito, ergo sum, (I think, therefore I am), expressed by Descartes, is a practical philosophy for many of us. Bruce's success as a writer is due in part to his ability to take complex subjects and express them in a readily understood manner, without going into minutiae and convoluted discourse.

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Continue with the inside story.
[{POST_SNAPBACK}][/a]

If you are interested in some more background on Bruce, Dan Margulis' comments, which are quoted on [a href=\"http://blogs.adobe.com/jnack/2006/12/in_memoriam_bru.html]John Nack's[/url] web site might be of interest.

Bill
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bjanes
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« Reply #52 on: December 29, 2006, 09:18:44 AM »
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I have (had) a lot of respect for Bruce, but it wasn't him who I was talking about.

As for the "magic numbers" for an 8x10, PK Sharpener doesn't currently take the print size into account (nor for that matter the gamma of the working space to generate the Blend If numbers) ... I've done my own tests ... so I'm not sure what you're talking about.
[a href=\"index.php?act=findpost&pid=92733\"][{POST_SNAPBACK}][/a]

In his Real World Sharpening with PSCS2, Bruce gives blend if numbers for gamma 1.8 (that of his preferred working space, ProPhotoRGB) and also gives the numbers for gamma 2.2 I'm not sure which numbers PK uses, but it would be a simple matter to open up the sharpening layer and look at the sliders and adjust them as necessary. As for print size, I think Bruce considered the angular limit of human perception and related this to the final resolution in the print in pixels per inch. If you assume a normal viewing distance, then the size of the print is implicit.

I don't really think that this is the appropriate time to antagonize Jeff. He as lost a dear friend and business partner and may be somewhat distraught.

Bill
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digitaldog
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« Reply #53 on: December 29, 2006, 09:30:20 AM »
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If you are interested in some more background on Bruce, Dan Margulis' comments, which are quoted on John Nack's web site might be of interest.

You'll get a lot more insight about Bruce on PSN that says more about Bruce and less about the persons writing it IMHO.
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Andrew Rodney
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« Reply #54 on: December 29, 2006, 10:26:11 AM »
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As for print size, I think Bruce considered the angular limit of human perception and related this to the final resolution in the print in pixels per inch. If you assume a normal viewing distance, then the size of the print is implicit. [a href=\"index.php?act=findpost&pid=92761\"][{POST_SNAPBACK}][/a]

Correct. . .normal viewing distance is "generally" thought of as being backed off to see the entire image in the field of vision (although Bruce liked to say that for photographers, the viewing distance was limited only by the length of their nose).

So, based upon what vision can resolve, you need to determine the optimal resolution for the viewing distance and re-ratio the image size/ppi resolution for optimum final print size resolution. Using "native file" resolution (without resampling) is optimal as long as the ppi falls between 180ppi for large prints and under 720ppi for small prints (although we've never found that over 480ppi is useful). If the native file is OVER 720ppi for the print size, you're better off down sampling...

Once you set the ratio for size/ppi, THEN you run the output sharpening based upon the image's current pixel/inch (or CM) as Bruce determined that sharpening isn't really impacted by viewing distance, only pixel density of the printed file.
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« Reply #55 on: December 29, 2006, 10:58:56 AM »
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You'll get a lot more insight about Bruce on PSN that says more about Bruce and less about the persons writing it IMHO.
[{POST_SNAPBACK}][/a]

Here's a direct link to the story Andrew mentioned with over 160 comments-many from people who didn't know Bruce personally (and some that did)...

[a href=\"http://photoshopnews.com/2006/12/14/bruce-frasers-serious-illness/]Bruce Fraser's Serious Illness[/url]

Add your own comments if you wish...we'll be holding a industry tribute to Bruce this coming Jan 10th at Macworld in San Francisco-if you are in the Bay area, attendance is free (registration required-more info on PSN shortly).
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bjanes
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« Reply #56 on: December 29, 2006, 12:01:54 PM »
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You'll get a lot more insight about Bruce on PSN that says more about Bruce and less about the persons writing it IMHO.
[a href=\"index.php?act=findpost&pid=92763\"][{POST_SNAPBACK}][/a]

Andrew,

I read on the Adobe Color Management (person's identity won't be mentioned here   ) that Dan's comments were self serving. Like Ray, I am very much at the periphery of the digital imaging circles, but I do know that Dan and you have disagreed about matters concerning the necessity of bit depth and that Dan often clashed with Bruce. Most of the comments on PSN are from Bruce's fans and I thought that comments from someone commonly thought of as a Bruce antagonist would be of interest.

Bill
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Ray
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« Reply #57 on: December 29, 2006, 12:05:43 PM »
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The concept that much of our existence might be an illusion is not unique to eastern thought and Aristotle's allegory of the cave presents a similar concept.

Bill,
Why have you written Aristotle when the link you refer to is about Plato. The cave allegory is Plato's, is it not?

Yes, of course, ideas travel around, but Buddha lived quite a few years earlier than Plato and millions of people in the meantime have made a religion from his teachings, whereas the legacy of Socrates, Plato and Aristotle seems to be mainly a curiosity of early philosophical development, except perhaps some of Aristotle's logic. Much of what they had to say we now know is simply wrong. I mean, who in his right mind would want to live in a Plato's Republic?  

Anyway, this is the wrong forum for such discussions.
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bjanes
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« Reply #58 on: December 29, 2006, 12:29:02 PM »
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Bill,
Why have you written Aristotle when the link you refer to is about Plato. The cave allegory is Plato's, is it not?

[a href=\"index.php?act=findpost&pid=92785\"][{POST_SNAPBACK}][/a]

Excuse me, the allegory is from Plato. Yes, I agree this is not the proper time and forum for such discussions, but why did you bring up the topic in the first place?

Bill
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Ray
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« Reply #59 on: December 29, 2006, 05:55:37 PM »
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Yes, I agree this is not the proper time and forum for such discussions, but why did you bring up the topic in the first place?
[a href=\"index.php?act=findpost&pid=92788\"][{POST_SNAPBACK}][/a]

Because Jeff mentioned that Bruce Fraser was a Buddhist and that fact sort of resonated with me for the reasons given. If you believe that ultimately everything we see is an illusion (and I think we can say with some certainty that the perception of the color green does not have an external existence outside of the the mind of the perceiver), then I tend to think it becomes easier, from a philosophical standpoint, to work on cleverer and more sophisticated methods of image manipulation.

Conversely, a person who believes in the absolute reality of the external world as perceived by the senses, is more likely to have a moral objection to any form of image manipulation.
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