[Digikam-users] Digikam internal precision?

[Bartek Pietrasiak]

>
>
>
> Ok. If you have from the start more informations, you don't want to waste
> them in the calculations working in 8 bits.
> 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.
>
> 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.
> 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.
>
> So this could be useful if we do more operations on the images, don't you
> think?
>
> bye
> gerlos
>
>
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.
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?
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 ;)
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