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mutta ilmeisesti kuvaaja tai kamera on säätänyt kuvaa hieman:
> I'm still gonna disagree on the photoshopping. It doesn't make sense.
> First off, only two of the photos are exposed for the sky -- if he
> was going to photoshop one, why not the others?
Ryan, we're not quite thinking on the same terms yet. The other two shots
probably did see some photoshop... or maybe they didn't. The difference is
the shots that Neal and I are saying are photoshopped are because the
contrast is enhanced beyond reality... most likely by the "auto level"
function. Every shot created has a histogram. This is basically a
graphical way to see what your shot is composed of... R G B, and intensity.
If you take a picture zoomed in on some clouds, all the camera really see is
various shades of grey with maybe some tint of other colors. On a
histogram you would see a really narrow bar that would not expand to the
entire length. When you auto level a picture, it essentially drags what
you see in thehistogram to fit the whole range. Since you had so little
color in the original picture, it over-exaggerates.
Example:
Here is a shot of some mammatus of may 12, 2004. Take my word that this is
properly exposed and this IS what the eye sees.
Shot #1 http://ww2.convectionconnection.com:8080/CHASE-051204/crw_9509.htm
Now look at a zoomed in shot to one specific "breast of mammatus".
Shot #2 http://ww2.convectionconnection.com:8080/CHASE-051204/crw_9529.htm
See how the colors are significantly enhanced, and more noise is apparent?
This is because when I quickly put up pictures to my website, the software
goes through and automatically auto-levels the pictures. While 99% of the
time, this is a quick way to digital darkroom and get a decent picture, on
the 1% of COMPLETE cloud shots, it goes overboard.
Here is a histogram comparison before and after.
http://www.convectionconnection.com/histofun.jpg
See how the second shot needs more correction? This is why these shots have
much more noise than the other.
> silhouette shot. If you look at the histograms for the photos, you'll
> see that the "darker" version is pretty much perfectly exposed for the
There isn't a use to looking at the histograms now. They are changed
because he photoshopped!
> For the "darker images", either his camera exposed it that way or he
> used photoshop to perfectly adjust the levels to match the data in the
> sky. (Using "brightness contrast" would probably not have achieved
> this histogram.) Yet, if he was savvy enough to photoshop two of the
> photos, why wouldn't he have been savvy enough to adjust the levels on
He did, but because the shots with landscape in the foreground contain more
colors, the auto-level function didn't have to expand the available data to
the end. It was already widespread.
>The photography
> strikes me as that of just an average stiff with a camera and, since
> there is no EXIF info at all in the file, I'm going to guess that it
> was taken with a consumer end digital camera, not a professional
> camera. (High end pro cameras put EXIF info into the file -- time
> taken, aperture settings, shutter speed, etc.)
Although I wouldn't base my decision by the EXIF data (lord knows where it
went after he photoshopped all four photos) I will say it wasn't a DSLR
because the aspect ratio is 4:3 not 35mm.
> the two stadium shots, you can see from the cloud configuration that
> they're almost identical.
Agreed. They are at the same time. So either a) they are photoshopped or b)
his camera is really shitty and does auto-leveling inside the body which
would be forced camera photoshopping. Remind me never to get this camera
(whatever it is).
So now that I think about it... maybe the arguement really isn't about
whether they photoshopped or not. Perhaps the real question who did the
auto-leveling.
Aaron
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