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Re: [ARSCLIST] Shopping for AD/DA
I ran into that problem when I was designing my web page. The pictures
were resized, stretched a little, brightened, and the quality was
reduced so it wouldn't take too long to download. The end result was
awful. After just a couple steps, the digital artifacts started showing
up. I just figured it way my free Photoshop program (you get what you
Don Cox wrote:
On 11/07/07, phillip holmes wrote:
I know you weren't. That was merely an "amen" for Bob. Most decent
ADCs can give good results, if they are used correctly. That's why I
don't like those "restorations". They "put lipstick on the pig" and
the result is unacceptable for me and the pig.
There was a great article about Pro-tools a while back. It explained
how all that manipulation in the digital domain gives such a bad
sounding product because every manipulation of the original signal
looses bit depth (or something like that---I'm an idiot about
If you have access to Photoshop, you can see a visual equivalent.
Load in a color photo, ideally one that is too dark. Go to
Image->Adjust->Levels (or "Adjust Lighting->Levels" in PH Elements).
You will see a histogram showing 256 levels of brightness.
Adjust the sliders, which is the equivalent of adjust levels in audio,
so that the photo looks better.
See how the histogram breaks up - there are no longer 256 levels. The
gradation is now jumpy.
This is because, to change levels, the computer must map some pairs of
levels onto single levels. The more steps you have to start with, the
less trouble this causes.