03-07-2011, 02:23 PM
[quote name='PuxaVida' timestamp='1299500610' post='6572']
The "twisted color profiles" is an expression Walter pointed out, which is used for standart color profiles of ACR. When I push up exposure in ACR, it's not only the brightness which is adjusted. ACR does other manipulations on the image, and maybe this is why I've seen a big difference between two images with the following exif data:
f/5.6, 1/640, ISO 800
f/5.6, 1/640, ISO 200
On the image with ISO=200, the exposure was pushed up (+2) in ACR to have the same brightness with ISO 800 image (and nothing else was touched). The resulting image was clearly worse than the ISO 800 image in terms of IQ. It has more noise, over-saturated colors with high contrast and also has a less DR.
Serkan
[/quote]
I doubt it has anything to do with the colour profile. Its just the fact that its better to get the image exposed correctly before the A/D converter than afterwards. Its the same as an analogue music cassette, those with low recording levels would sound a little muffled and had more hissing noise when played at higher volumes. Those that were recorded at a better level would sound better all round.
(Also, I meant to say that you will notice a bigger quality difference in low light, ISO 800 f/5.6, 1/640 is quite bright and will give more defined light/shadow transitions. I expect the settings I did it at will show the quality difference a little more due to the lack of general light)
The "twisted color profiles" is an expression Walter pointed out, which is used for standart color profiles of ACR. When I push up exposure in ACR, it's not only the brightness which is adjusted. ACR does other manipulations on the image, and maybe this is why I've seen a big difference between two images with the following exif data:
f/5.6, 1/640, ISO 800
f/5.6, 1/640, ISO 200
On the image with ISO=200, the exposure was pushed up (+2) in ACR to have the same brightness with ISO 800 image (and nothing else was touched). The resulting image was clearly worse than the ISO 800 image in terms of IQ. It has more noise, over-saturated colors with high contrast and also has a less DR.
Serkan
[/quote]
I doubt it has anything to do with the colour profile. Its just the fact that its better to get the image exposed correctly before the A/D converter than afterwards. Its the same as an analogue music cassette, those with low recording levels would sound a little muffled and had more hissing noise when played at higher volumes. Those that were recorded at a better level would sound better all round.
(Also, I meant to say that you will notice a bigger quality difference in low light, ISO 800 f/5.6, 1/640 is quite bright and will give more defined light/shadow transitions. I expect the settings I did it at will show the quality difference a little more due to the lack of general light)