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Old Jan 14, 2007, 1:01 PM   #11
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Keeping in mind this isthe SMC FA 100-300 lens being discussed in another thread, here is a shot of what it does at its narrowest angle (highest magnification), where it is supposed to be "very soft."

This was shot at ISO 200, 1/250, F8.0, 300 mm. Then I did a reduction to 20% with no sharpening and saved at 98% JPREG Quality, using IrfanView.

This JPEG is 243 KB.




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Old Jan 14, 2007, 1:10 PM   #12
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Now I did one step of sharpening, which caused the saved picture to become 277 KB, which is too large to upload. Given this is a 72x72 dpi viewing environment, I saved the sharpened picture at 96% JPEG quality instead of 98%. That removed the really high fequency detail and got it down to 243 KB (again). You can not see that 2%differrence on a typical monitor.

Notice how much more "vivid" the scene is. Steve (digicams) has always recommended shooting soft and sharpening afterward. (Pop quiz: why not the reverse? )


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Old Jan 14, 2007, 1:15 PM   #13
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Here is a 450x450 pixel100% crop with nosharpening (258 KB), saved at 98% (229 KB) so I could upload it.





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Old Jan 14, 2007, 1:23 PM   #14
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Now I added one step of sharpening (258 -> 327 KB), and saved at 98% (232 KB).

This is just like the Tom Clancy movies zooming and "sharpening"from orbital view.

If the algorithm is good, then artifacts are not being added. A soft image is real information spread out over an "larger and overlapping" area. The question is, what is the correct proportion of ajacent convoluted information to acceptand are you guessing correctly how the original lens spread it out at different wavelengths.


I guess you all know by now: neverlet your Pentax ist* DL do the sharpening: the algorithm is artifact ridden!


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Old Jan 14, 2007, 4:18 PM   #15
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Love the sunset/sunrise shot.


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Old Jan 14, 2007, 10:13 PM   #16
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Definately love the color of that last shot.

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Old Jan 15, 2007, 1:49 AM   #17
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The Sunset is beautiful.

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