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<DIV dir=ltr align=left><SPAN class=083413422-21012010><FONT color=#0000ff
size=2 face=Arial>Excellent idea. What would be a good type of picture to
try it on? Perhaps one with areas with pixels close in value, to see
if they end up with the same value.</FONT></SPAN></DIV><BR>
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<FONT size=2 face=Tahoma><B>From:</B> Bartek Pietrasiak
[mailto:pietras.sp@gmail.com] <BR><B>Sent:</B> Friday, 22 January 2010 9:34
AM<BR><B>To:</B> digiKam - Home Manage your photographs as a professional with
the power of open source<BR><B>Subject:</B> Re: [Digikam-users] Digikam internal
precision?<BR></FONT><BR></DIV>
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<DIV class=im><BR><BR></DIV>Ok. If you have from the start more informations,
you don't want to waste them in the calculations working in 8 bits.<BR>But the
point is *also* that you want to lose as less information is possible when you
edit any image, since usually we do more than just one operation on our
photos.<BR><BR>If for example we do some blurring on a 8 bit image, we get
always 256 shades of gray. In some next operation, for example levels adjust,
we could reduce it to 200 shades of gray.<BR>But if we convert the same image
to 16 bits and then we apply the same blurring, we get 65536 shades of gray,
isn't it? If we do some other operations next, we still have a lot of shades
to work with, and this could help preserve detail in dark or light areas, no?
Even 30000 shades, less than the initial dynamics, are a LOT of
informations.<BR><BR>So this could be useful if we do more operations on the
images, don't you think?<BR>
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<DIV class=h5><BR>bye<BR>gerlos<BR><BR></DIV></DIV></BLOCKQUOTE>
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<DIV>It is funny, that we are talking about that. The advantage of the 16 bits
over 8 bits from a 8 bit file when a few operations
are performed seems to be logical. I shoot in raw and the raw
developers usually work with 16 bits, but I don't care. I've never tried to make
some raw developer to work on 8 bits because I've read many times that this is
the advantage of raw and I haven't checked this by myself. The white balance is
the main reason why I use raw now. </DIV>
<DIV>Now, I mean funny, because I've just realized that I also have this feeling
and non of us have never checked whether the difference can be spotted on a
final picture at all, not on its histogram, which can be easily done
;) So simply, can one of you/us, who made a few operation on some jpgeg, make a
test and tell us whether the difference can by spotted and show the
example?</DIV>
<DIV>When I get some jpges from some friends, family etc. the only thing
which I do is usually is to crop, curves or simply contrast and sharpen,
sometimes perspective and/or distortion correction. I have a feeling that
the difference can't be spotted when only those few operations
are performed. High time to check this ;)</DIV></DIV></BODY></HTML>