Color space Help

[Parias]

Hello all,

here's the thing... I tried shooting with my 300D witht the AdobeRGB space, as it has a much wider gamut than sRGB.. The problem is that when i open the image in PS7 (working space is Adobe RGB) and assign it the AdobeRGB profile, the image seems to get much darker shadows and gives the impression of increased contrast.. I wanna ask if this is normal?

Also i tried first assigning sRGB profile and then converting it to AdobeRGB, and in this case the shadows and overall contrast seem ok (just like if the image was shot with sRGB) but the colors are different than the ones in a same image shot in sRGB... Is this normal too?

Thank you in advance

[design crusader]

You are correct, the Adobe RGB Color Space does tend to appear heavier in the shadows and three-quarter tones, and it has a different sauration and hue threshold. I used to use ColorMatch RGB, it did not seem to plug up as much in the shadows and three-quarter tones, but it did not come close to Adobe RGB for color gamut. CANON intends for RAW shots taken in their Adobe RGB Color Matrix Setting to be ASSIGNed the Adobe RGB color space. Further,more, whether or not you were assigning the Adobe RGB color profile to an image from the CANON camera (10D) or any other image for that matter, the fact is that Adobe RGB typically does this to the appearance of the image.

If you ASSIGN the sRGB profile first and then CONVERT to Adobe RGB, then you are limiting it to the gamut of sRGB and then opening it up to Adobe RGB, but this really does not work like you might think. Consider this analogy, you are at the gas station and you go to fill up your cars 20 gallon tank and also fill up a 5 gallon gas can. Your 20 gallon tank is Adobe RGB and the 5 gallon gas can is sRGB. The gas can is more portable, and can go from car to car and will be exaclty the same in each, but it does not hold as much fuel as your 20 gallon tank. You can choose not to fill up your 20 gallon tank (Adobe RGB), instead you fill up the 5 gallon gas can (sRGB) and then decide to pour the gas from the can into the tank -- it will not fill up the tank. Thus, an sRGB ASSIGNed image CONVERTED to Adobe RGB will not flow into the fill the color gamut of Adobe RGB.

Make sense?

[Jesper]

The problem with the 10D and the accompanying software for the PC, and I guess this is the same with the 300D, is that it does not save the color profile in the TIFF or JPEG file if you set the camera to Adobe RGB.

Because the image file does not contain a (reference to) a color profile, Photoshop will assume that the file is in the default sRGB color space. This will make Adobe RGB files look wrong, most notably the colours will look desaturated.

You should assign (not convert) the Adobe RGB profile to the image to view it correctly.

Don't assign sRGB and convert to Adobe RGB, that's a wrong way of working.

[Parias]

Thak you guys for your in-depth analyses... The real problem (question) i had was about the darkening of the shadows, but it seems that it is normal that it happens...

So, i do assign AdobeRGB when opening the image, work with it making all the adjustments (including lightening up the shadows to show the detail that i know is there) and save it and take to the lab for printing and it should be ok...