Topic: 8-bit versus 16-bit tiff files

Thanks for the reply to my post yesterday re. using a silent track.  I have had no trouble implementing that.

Could I ask you another question about the input tiff files, 16-bit versus 8-bit. All of my original files have been calculated from ImageJ, and are 8-bit/channel RBG files.

I have read about this in relation to OpenDCP, and watched a number of the online help videos.  Most presenters say that it is very important that the tiffs are 16-bit/channel, though some say OpenDCP will accept 8-bit/channel, but the quality will not be as good.  Then in these demos they change their 8-bit files to 16-bit and suggest the problem is solved.

My understanding when you simply go from 8-bit to 16-bit is that all pixel values are multiplied by 256; so for example, if 8-bit pixel counts are 20 and 21 they will become 5120 and 5376, and there will be NO pixels with values between 5120 and 5376. Consequently I do not see how the next conversion to JPEG2000 (XYZ) can be any better than if the conversion was done from the original 8-bit files.

Could you enlighten me if I am wrong, and clarify whether OpenDCP will accept 8-bit/channel with no quality loss compared to 16-bit files derived from 8-bit files.

Many thanks

Robert

Re: 8-bit versus 16-bit tiff files

If you source material is 8-bit, then create 8-bit TIFFs, then use those with OpenDCP.