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Re: [APML] Layers
Hi Alan
>Is it OK to convert to 8 bit then back to 16?
No!!!! Avoid that! You are lossing a lot of data when reducing the bit deph/accuracy. Lets see an example. If you have a 2bits image you can see black, white, and two different grays (four levels, 2^2). If you convert the image to 1bit, you will see black or white only (2^1, two levels). The two gray lavels have been merged with the other two levels. If you go back to 2bits, there is no way you can know wich black or white level was originally a gray level, so that information has been lost, and you will see only black or white too.
>I'm still not sure if
>that action alone is detrimental to the data. Or, is the simple act of
>doing the conversion both ways enough to harm what we're working on?
Yes, it is harmfull to the data. From a true 12bits image (a raw SS400 scan) with 4096 levels you are obtaining only 256 levels (2^8). So, you merged every 16 levels into only one. That is a huge lost!
Regards,
Carlos Milovic F.
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Astro & Photo - CMF
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