1 |
On Tuesday 08 Sep 2015 23:49:21 wraeth wrote: |
2 |
> On 09/09/15 04:42, Mick wrote: |
3 |
> > On the same hardware I noticed that a CMYK photograph converted to |
4 |
> > sRGB looked mostly the same (indistinguishable) on Linux, but the |
5 |
> > sRGB colours were brighter on MSWindows. |
6 |
> > |
7 |
> > I tried this by dual booting between MSWindows and Linux. |
8 |
> > |
9 |
> > Then I tried it by running MSWindows within a VM on a Linux host |
10 |
> > and the MSWindows showed a clear difference in brightness between |
11 |
> > the two formats. |
12 |
> > |
13 |
> > Finally, I checked on an AppleMac and the difference between the |
14 |
> > CMYK and sRGB photographs was even more prominent than MSWindows. |
15 |
> > |
16 |
> > So, the Linux renedering seems to be misleading the user. Have you |
17 |
> > noticed the same? |
18 |
> > |
19 |
> > BTW, both Linux machines that I tried this on are running radeon |
20 |
> > drivers - are these to blame? The AppleMac is running Intel |
21 |
> > graphics with its 'retina' monitor. Is it a matter of somehow |
22 |
> > tuning the Xorg settings on my Linux PCs? |
23 |
> |
24 |
> While I'm certainly not an expert on this sort of thing, one key piece |
25 |
> of information that would affect this is what software you used. |
26 |
> Specifically, did you use the same software on each platform |
27 |
> (therefore the same method of conversion)? |
28 |
|
29 |
The conversion from CMYK to sRGB was performed on Linux. The user |
30 |
experimented with different CMYK.icc and sRGB.icc files using imagemagick and |
31 |
also Gimp. Then the original CMYK and resultant sRGB files were moved around |
32 |
different PCs and OS and their difference observed. The difference was more |
33 |
prominent in a MacBook Pro, next (almost equally) visible in MSWindows 7 |
34 |
either run natively or in a VM and finally least visible difference (you had |
35 |
to squint to see it) was in the Linux PCs. |
36 |
|
37 |
The only common thing between the Linux PCs was that they are both running |
38 |
Gentoo but have different radeon cards & different firmware. |
39 |
|
40 |
-- |
41 |
Regards, |
42 |
Mick |