8 bit vs 16 bit

[Jonathan Ashton]

I would appreciate a little advice here please. I have a Canon 20D Canon 50D and hopefully from today a Canon 7D. My lenses are Canon L lenses. I generally use Adobe RAW and CS4 and I have the latest updates installed, my PC monitor is fully calibrated, I set my cameras to sRGB and of course when emailed the jpegs are sRGB.
When I do produce prints for club competitions I get my pal to print them for me - he has a fully spec'd professional studio - he is a magazine editor so I can confidently say everything is absolutely spot on from the calibration point of view.
Until fairly recently I always launched from RAW using 8 bit, I then went on to 16 bit and saw no difference though I did note there was a difference in the histograms. Eventually I sort of convinced myself I could see a difference in 16 bit v 8 bit but I have to confess I think the difference is minimal and only when I placed two identical images processed in 8 bit vs 16 bit side by side did I think I could see a difference BUT an awful lot depends upon the ambient light in the room in which my monitor is situated and I am wondering if this is a more significant issue.
I appreciate I am answering my own question to a large extent but I really would appreciate your views on the use of 16 bit vs 8 bit given the equipment I own and have access to.:)

[Axel Hildebrandt]

The differences may not be dramatic but for print I think you made the right choice to use 16 bit and TIFF(?). Otherwise you would unnecessarily throw away information. In camera I use Adobe RGB and only go to sRGB when saving for web use.

[Jonathan Ashton]

The differences may not be dramatic but for print I think you made the right choice to use 16 bit and TIFF(?). Otherwise you would unnecessarily throw away information. In camera I use Adobe RGB and only go to sRGB when saving for web use.

Thanks Axel, do you use Adobe RGB in camera because it has a wider colour range or because you may be supplying images to agencies who require Adobe as opposed to sRGB?

[Axel Hildebrandt]

Thanks Axel, do you use Adobe RGB in camera because it has a wider colour range or because you may be supplying images to agencies who require Adobe as opposed to sRGB?

I use it because of the wider gamut throughout the process from camera to PS and the histogram in-camera seems to be closer to what you see in ACR (combined with lowering the contrast setting in-camera).

[Doug Brown]

I use 16 bit and Adobe RGB (sRGB for the web). 16 bits isn't always necessary; as evidence, look at the 8 bit JPEGS that your camera can produce. But if you're trying to salvage the far right and more importantly the far left of the histogram, 16 bits can be indispensable.

[Michael Gerald-Yamasaki]

Jonathan,

Greetings. The most likely place to actually see the impact of 8 bit vs 16 bit processing is when your image is on the hairy edge of showing color banding (and even at that the banding may show up on screen, but not show up in print). Most computer monitors are not capable of showing a difference out to 16 bits (while very high quality prints may).

From experience, I'd say you'll never see a difference on screen or in print. From practice, I can't bring myself to throw away all that information prior to processing. ;)

Uh, unless you're working in mono-chrome, where there are only 256 levels in 8-bit, but 64K levels in 16-bit. Then you for sure want to be in 16-bits.

I shoot aRGB 14-bit, process in ProPhoto 16-bit tiffs, and print 8-bit sRGB jpegs (mostly).

Cheers,

-Michael-

[Jonathan Ashton]

Thank you for taking time to reply everyone, I have decided to use 16 bit in Adobe RAW from now onwards for all images.:cool: