Monitor Colour settings

Chaz Photos

Jack Elam
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Chaz
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HI since putting Google analytics on to my new updated web site, I was surprised at how many have there monitor set to only 24bit.
Out of 61 visitors over the few days I have updated it I have had 41 with 32-bit and 20 -24-bit

As most I think are photographers from here and another place I have asked for comments on how my new site was looking, I was surprised so What setting have you got?
If only 24-bit why?

Cheers
 
24 bit = 32 bit.

24bit is 8 bits for R, G and B each. 32 bits is 8 bits for R, G and B plus 8 bits spare to pack to 32 bits. Computers work better on boundaries that are powers of two.

The only time you'll get more than 8 bits R/G/B is if you're using a 10 bit workflow. You're talking the Pro cards from Nvidia and ATI for that (Nvidia Quadro/ATI FirePro).
 
24 bit = 32 bit.

24bit is 8 bits for R, G and B each. 32 bits is 8 bits for R, G and B plus 8 bits spare to pack to 32 bits. Computers work better on boundaries that are powers of two.

The only time you'll get more than 8 bits R/G/B is if you're using a 10 bit workflow. You're talking the Pro cards from Nvidia and ATI for that (Nvidia Quadro/ATI FirePro).

but 24-bit is slower
than 32 bit. This is because a memory 'fetch' is done in word (i.e. 32-bit)
chunks. When you've fetched the first 32-bit word, if you're running in
32-bit mode, then that's that; the required 24-bit value is there,
right-aligned in the word (i.e. the first 8 bits are zero). Subsequent
word-fetches bring in the next values, etc. In the case of 24-bit colour,
the fetch is still 32-bit, but the 24-bit value you want is left-aligned in
the word, so the logic has to shift the value right, dropping off the bottom
eight bits. Instant problem; those eight bits you've just 'dumped' are in
fact the first 8 bits of the NEXT 24-bit value, so you've got to store them
somewhere! Then, you bring in the next 32-bit word; the first 16 bits are
the right-most 16 bits of the next pixel (plus the 8 bits you just stored
earlier), and the next 16 bits are the first 16 bits of the third pixel, and
so on. That's why 32-bit is far preferable to 24-bit.

Plus I do not have 24-bit on my settings...
 
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but 24-bit is slower
than 32 bit.
You will find that PCs that report 24 bit are actually running 32 bit (if they are not, the graphics card will have hardware to compensate). Both are correct: 24 bit useful packed in 32 bit word. They are equivalent - whether the computer reports 24 or 32 doesn't really matter. And access times will not be compromised.

The 8 bits "spare" is often used to hold transparency information.
 
I'd be more concerned about colour spaces and whether your potential client is seeing the same as what you do.

I've lost count how many times I've told our graphics lot not to supply the e commerce lot with cmyk profiled images for the website..
 
but 24-bit is slower
than 32 bit. This is because a memory 'fetch' is done in word (i.e. 32-bit)
chunks. When you've fetched the first 32-bit word, if you're running in
32-bit mode, then that's that; the required 24-bit value is there,
right-aligned in the word (i.e. the first 8 bits are zero). Subsequent
word-fetches bring in the next values, etc. In the case of 24-bit colour,
the fetch is still 32-bit, but the 24-bit value you want is left-aligned in
the word, so the logic has to shift the value right, dropping off the bottom
eight bits. Instant problem; those eight bits you've just 'dumped' are in
fact the first 8 bits of the NEXT 24-bit value, so you've got to store them
somewhere! Then, you bring in the next 32-bit word; the first 16 bits are
the right-most 16 bits of the next pixel (plus the 8 bits you just stored
earlier), and the next 16 bits are the first 16 bits of the third pixel, and
so on. That's why 32-bit is far preferable to 24-bit.

Plus I do not have 24-bit on my settings...

Is there an English version of this Chaz :lol:
 
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