Hello! Images with 16 bit resolution in general do not need any compression or gamma curves. They can be stored as transmission or reflection data (linear data). If you are converting to 8 bit data formats you need some compression of the dynamic range (Lstar, gamma, modified gamma with linear sloop in the shadow area). Different color spaces use different parts of the coding range. With 16 bit resolution you can use any color space that is large enough not to clip any colors. Using 8 bit resolution you should use a color space that is large enough that all possible codings were not clipped and small enough not to waste space. Wide gamut color spaces in 8 bit coding tend to create artifacts like bending. Therefore it is best to choose a smaller color space in this case (AdobeRGB, ECIRGB). Guenter Bestmann ________________________________ From: eci-en-admin(a)lists.transmedia.de [mailto:eci-en-admin@lists.transmedia.de] On Behalf Of Jón A Sandholt Sent: Wednesday, June 01, 2005 2:23 PM To: ECI Subject: [ECI-EN] ECIRGB versus LstarRGB This is a very interesting discussion, wich I have been following with great interest. I have a question that relates to this topic. How does bit depth ( 8 bit vs 16 bit etc.) relate to all this.We are told that 8 bit color can give us about 16,7 million colors and 16 bit something much more (I don't wont even try to do the calculations).I know this is only in theory but lets say you have a 8 bit image in ProPhoto RGB and one thats 16 bit in the same colorspace, is there a difference between them as to how much part of the space they use? What I'm trying to say is does a high bit image make a better use of a large colorspace than the 8 bit one? Am I missing some point here or misunderstanding something? Thanks again for very intersting discussion. Best regards. Jón A Sandholt