Ah - excellent. Thanks. So, referring to the very valid point that - taking 8-bit colour here to mean 8-bit per channel and hence we are 'actually' talking about 24 bit images (referred to as True Color!) - the human visual system can only see roughly the eqiuvalent of the 16.7 million colours produced by 256³ (3 x the 8-bit channels), is the purpose of 16 bit colour (hence, 48 bit colour) simply to enable accurate conversion between devices? Are there calculations performed by software/devices/operating systems that allow each device to connect to the Profile Connection Space more accurately using the greater information in 16/48 bit image space? I suppose what I'm asking in another sense is why use 16 bit colour at all in a practical sense? I understand that it is 'better' in a mathematical sense but again, if the printer works within something more akin to 8/24 bit colour, what's the deal? -- Alan Ansell aansell@... ----- Original message ----- From: CDTobie@... To: DigitalBlackandWhiteThePrint@yahoogroups.com Date: Tue, 10 Apr 2007 11:22:48 EDT Subject: Re: [Digital BW] Re: 8bit to 16 bit In a message dated 4/10/07 10:59:30 AM, [1]aansell@... writes: > A fascinating debate this and I might be overlooking something fundamental > here, but in an attempt to ensure I am following this correctly: Is this > discussion about 8-bit images in what is referred to as 8-bit TrueColor ie that > each pixel has a value described by 8 bits to represent its RGB value. If so - > or if in some other case - then how can data be considered to be 'shifted' > or 'hidden'? If it cannot be described in 8 bits, then surely it cannot exist > within the current colour space? > 8 bits per channel, means 256 levels per color channel. Anything more is treated as 16 bits per channel by Photoshop. So 10 to 12 bit camera files rattle around in 16 bit space; while 8 bit files converted to 16 rattle even more. But we can only see 8 bits per channel of even our high bit files; photoshop deals with that as the "displayable" portion, while dragging whatever else is in between along for the ride. And we can only print about (notice I said ABOUT I don't care to argue exactly how much data can be printed yet again! <G>) 8 bits per channel worth, so whether any data dumped, as I said earlier, through the cracks in the 8 bit/channel visible floorboards of our 16 bit/channel Photoshop image, into the Midden of Extra Bits Below, may or may not ever resurface to do us any good. Sorry to be waxing quite so analogous today, but the 'Midden of Extra Bits Below' is nearly as much fun as the '8 bit floorboards' that Ernst was complementing earlier! <G> C. David Tobie Product Technology Manager ColorVision Business Unit Datacolor Inc. [2]CDTobie@... www.colorvision.com ************************************** See what's free at [3]http://www.aol.com. [Non-text portions of this message have been removed] References 1. mailto:aansell%40fastmail.fm 2. mailto:CDTobie%40colorvision.com 3. http://www.aol.com/ 4. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/message/84771;_ylc=X3oDMTM2b2xqazRhBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBG1zZ0lkAzg0Nzk5BHNlYwNmdHIEc2xrA3Z0cGMEc3RpbWUDMTE3NjIxODYwNQR0cGNJZAM4NDc3MQ-- 5. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/post;_ylc=X3oDMTJxczk0c2dkBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBG1zZ0lkAzg0Nzk5BHNlYwNmdHIEc2xrA3JwbHkEc3RpbWUDMTE3NjIxODYwNQ--?act=reply&messageNum=84799 6. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/post;_ylc=X3oDMTJlcDNvYWljBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwNmdHIEc2xrA250cGMEc3RpbWUDMTE3NjIxODYwNQ-- 7. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/messages;_ylc=X3oDMTJlNWFtcHBmBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwNmdHIEc2xrA21zZ3MEc3RpbWUDMTE3NjIxODYwNQ-- 8. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint 9. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/ 10. http://groups.yahoo.com/;_ylc=X3oDMTJkdDllMmdyBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwNmdHIEc2xrA2dmcARzdGltZQMxMTc2MjE4NjA1 11. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/join;_ylc=X3oDMTJmdTFqMzVkBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwNmdHIEc2xrA3N0bmdzBHN0aW1lAzExNzYyMTg2MDU- 12. mailto:DigitalBlackandWhiteThePrint-digest@yahoogroups.com?subject=Email%20Delivery:%20Digest 13. mailto:DigitalBlackandWhiteThePrint-traditional@yahoogroups.com?subject=Change%20Delivery%20Format:%20Traditional 14. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint;_ylc=X3oDMTJkZHBwZzNlBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwNmdHIEc2xrA2hwZgRzdGltZQMxMTc2MjE4NjA1 15. http://docs.yahoo.com/info/terms/ 16. mailto:DigitalBlackandWhiteThePrint-unsubscribe@yahoogroups.com?subject= 17. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/members;_ylc=X3oDMTJmN2k5Y3NsBF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwN2dGwEc2xrA3ZtYnJzBHN0aW1lAzExNzYyMTg2MDU- 18. http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint;_ylc=X3oDMTJldGJlMmx1BF9TAzk3MzU5NzE0BGdycElkAzM3MDIzMTEEZ3Jwc3BJZAMxNzA1MDE5MTgyBHNlYwN2dGwEc2xrA3ZnaHAEc3RpbWUDMTE3NjIxODYwNQ-- 19. http://groups.yahoo.com/gads;_ylc=X3oDMTJjdXBqYXY2BF9TAzk3MzU5NzE0BF9wAzEEZ3JwSWQDMzcwMjMxMQRncnBzcElkAzE3MDUwMTkxODIEc2VjA3NsbW9kBHN0aW1lAzExNzYyMTg2MDU-?t=ms&k=Fine+art+photography&w1=Fine+art+photography&w2=Digital+photography&w3=Digital+photography+print&w4=Digital+photography+technique&w5=Fine+art+photography+print&c=5&s=149&g=2&.sig=AhyJLEY_mHSSQCNHMyZ1HQ 20. http://groups.yahoo.com/gads;_ylc=X3oDMTJjb2podnJ0BF9TAzk3MzU5NzE0BF9wAzIEZ3JwSWQDMzcwMjMxMQRncnBzcElkAzE3MDUwMTkxODIEc2VjA3NsbW9kBHN0aW1lAzExNzYyMTg2MDU-?t=ms&k=Digital+photography&w1=Fine+art+photography&w2=Digital+photography&w3=Digital+photography+print&w4=Digital+photography+technique&w5=Fine+art+photography+print&c=5&s=149&g=2&.sig=SvQKuVtg6IzggzvbNW76cQ 21. http://groups.yahoo.com/gads;_ylc=X3oDMTJjMTBzZnA0BF9TAzk3MzU5NzE0BF9wAzMEZ3JwSWQDMzcwMjMxMQRncnBzcElkAzE3MDUwMTkxODIEc2VjA3NsbW9kBHN0aW1lAzExNzYyMTg2MDU-?t=ms&k=Digital+photography+print&w1=Fine+art+photography&w2=Digital+photography&w3=Digital+photography+print&w4=Digital+photography+technique&w5=Fine+art+photography+print&c=5&s=149&g=2&.sig=g1PLpDs3VAJRCiHquYf9Kw 22. http://groups.yahoo.com/gads;_ylc=X3oDMTJjNWpqY3BuBF9TAzk3MzU5NzE0BF9wAzQEZ3JwSWQDMzcwMjMxMQRncnBzcElkAzE3MDUwMTkxODIEc2VjA3NsbW9kBHN0aW1lAzExNzYyMTg2MDU-?t=ms&k=Digital+photography+technique&w1=Fine+art+photography&w2=Digital+photography&w3=Digital+photography+print&w4=Digital+photography+technique&w5=Fine+art+photography+print&c=5&s=149&g=2&.sig=z42wd62NioHid6gdeL6dXQ 23. http://groups.yahoo.com/gads;_ylc=X3oDMTJjMmRwN2kwBF9TAzk3MzU5NzE0BF9wAzUEZ3JwSWQDMzcwMjMxMQRncnBzcElkAzE3MDUwMTkxODIEc2VjA3NsbW9kBHN0aW1lAzExNzYyMTg2MDU-?t=ms&k=Fine+art+photography+print&w1=Fine+art+photography&w2=Digital+photography&w3=Digital+photography+print&w4=Digital+photography+technique&w5=Fine+art+photography+print&c=5&s=149&g=2&.sig=a-SzixGQMrtqCBQRWDYQjw 24. http://us.ard.yahoo.com/SIG=12iffcvvi/M=493064.9803190.10510181.8674578/D=groups/S=1705019182:NC/Y=YAHOO/EXP=1176225805/A=3848611/R=0/SIG=12t54fmfj/*http://news.yahoo.com/i/753;_ylt=A9FJqYYsvq5E.kwAkwOyFz4D;_ylu=X3oDMTA2NWJlcmlsBHNlYwN0bg-- 25. http://us.ard.yahoo.com/SIG=12j9g672q/M=493064.10512181.11138666.8674578/D=groups/S=1705019182:NC/Y=YAHOO/EXP=1176225805/A=4507179/R=0/SIG=12de4rskk/*http://us.rd.yahoo.com/evt=50284/*http://finance.yahoo.com/personal-finance 26. http://us.ard.yahoo.com/SIG=12ie0572a/M=493064.9803235.10510228.8674578/D=groups/S=1705019182:NC/Y=YAHOO/EXP=1176225805/A=4491577/R=0/SIG=11mllii3e/*http://tv.yahoo.com/american-idol/show/34934/photos/ [Non-text portions of this message have been removed]
Message
Re: [Digital BW] Re: 8bit to 16 bit
2007-04-10 by Alan Ansell