Originally posted by biz-engineer Looking through old JPEG from when I started with the K200D, I've found some sunset images out of gamut.
Out of sRGB gamut? How was it possible? Simple, in camera saturation was too much and there is no way to check for out of gamut with the built in camera JPEG conversion, and at that time I wasn't well ware about what color space really meant (and now it is not possible to recover the out of gamut from JPEGs).
How have you determined there are "out of gamut" colours in your JPEG photos? Presumably, it's by loading them into a photo editing suite and toggling the out of gamut warnings? Which leads me to ask, what output profile have you selected within the software?
So far as I understand - and I'm sure someone will correct me if I'm mistaken - the out of gamut warnings are telling us that there are colours in the currently loaded image that aren't covered by the output gamut; so, if your photo uses the AdobeRGB colour space, you load it into your photo editing software and the output profile is set to sRGB, there's a very strong possibility that areas of the photo will show as out of gamut. But if you set the output profile to AdobeRGB, none of the photo's colours should be out of gamut.
Originally posted by biz-engineer At the time, should I have used the Adobe RGB color space instead of sRGB? Not so sure about that, because it seems Adobe RGB JPEG (8bits) comes with a loss of tone resolution for everything inside the gamut. It seems the 16bits depth of ProPhoto RGB addresses that limitation.
Arguably, if you're intending to post process files for a variety of existing and future output media, you should shoot using the widest available gamut - on the basis that you can always convert to a smaller gamut after the fact. In reality, sRGB is the de facto standard for on-screen viewing, and most mass-market commercial printers either expect - or will at least accept - sRGB files. I would guess professional printing services accept wider gamut images.
But, really, you should have been shooting raw rather than JPEG - in which case, colour space doesn't matter... the limitations are those of the sensor and your exposure settings. Then, when processing your raw files, you can select the output colour space as required for the target medium or service.
Originally posted by biz-engineer Not only Adobe RGB is still 8bits deep per channel, but the Adobe color gamut isn't that much larger than sRGB, saturation still can easily clip pure reds in images. It seems sRGB is the standard requested by all photo development/printing labs, although recent printers are able to exceed the color gamut of Adobe RGB.
AdobeRGB is is approximately 35% larger, which isn't insignificant. But whether this is even represented in a JPEG file using the AdobeRGB colour space, I honestly don't know.
Originally posted by biz-engineer Was Adobe RGB a pseudo standard that came out of the blue from Adobe for the sake of strengthening their business?
Not sure, but I'm confident someone here will know