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View Full Version : R.G.B or Adobe R.G.B what to do ? .



gje38752
17-11-2010, 8:38pm
I am interested to know the difference between using RGB or Adobe RGB the manual for my 50D indicates you should stick with RGB . There must be a reason for Adobe RGB to be included in the menu. ? Which is the best to use.:rolleyes:

Kym
17-11-2010, 8:55pm
Simple version:

sRGB is required for web publishing and most print shops and monitors support it.

aRGB is a wider gamut (greater range of colours) but you end up having to convert to sRGB so stay with it for most things.

The more detailed version is to use bigger gamut colour space until final production - but that means a bit more work and need to be careful

arthurking83
17-11-2010, 9:13pm
Best to use raw for capture!!

(I hope you;re thinking ... :confused:)

When you shoot raw in camera the colour space you set the camera too makes no difference to the image, in any way shape or form.
It's debatable if the review screen may be able to display any subtle differences between an sRGB or aRGB file, BUT!! whatever(colourspace) you choose in camera will also affect the embedded JPG file in the raw image.

I prefer to shoot in sRGB mode and stay in the sRGB mode, but that's because I shoot in raw format and converting the (once) sRGB raw file into an aRGB file is trivial and easy.
In your editing software there will be a setting to convert the raw file into whatever colourspace you subsequently desire.
If the vast majority of your final images are for web display/screen display/etc, then sRGB is more than enough.
If the majority of your images at the final stage are for super high quality printing then aRGB is best(for that print service). Lots(or most) printing services will want sRGB colourspace(IIRC the quick print service providers that use Kodak Kiosks, only recognise the sRGB colourspace anyhow.. but that may have changed).

I shoot in sRGB(makes the embedded jpg more 'compatible'), edit in sRGB, upload in sRGB and if I ever want a high quality print(which I got a few weeks ago), I go back to the image in question, re-save it the adobeRGB colourspace format and give it to the printer.

Note! sometimes you may see a colour shift when converting the original image from either colourspace to the other. This can be normal(I usually see a darken/saturation in the greens, if they're vivid in the sRGB file) and is easy to re edit the file to desaturate/brighten if it's over the top.

another note!
Some image viewing programs like to use the embedded jpg file for displaying the raw file.
This can be a problem if you've shot in sRGB and want to now covert the raw file into aRGB(or any other larger colour space, like ProPhoto).
So what'll happen is that the raw file looks distorted, where the embedded preview file is set to sRGB and the software is expecting to see aRGB instead, there is a strange colour shift.. but only in the preview file.
Bottom line is don't convert the raw file. ever!!!! only convert the colourspace for the final output, which may be either jpg or tiff depending on the level of quality you want.

Also! FWIW, the vast majority of consumer grade screens can't see the adobeRGB colourspace. You need a semi high end screen to at least come close(and even then they're apparently a psuedo-mock representation anyhow. The real McCoy screens cost in the multi thousands of dollars, the semi high end use some kind of internal bit conversion to display the colours properly.
SO??? if there is a very high chance that your screen can't display the entire aRGB gamut, then ask yourself why you'd want to not really see it all as it should be ;) If that sounds silly, it;s because it really is. why use aRGB if you screen is only capable of displaying sRGB.
For print, it's different. the printer usually can produce (at least some of) the colour range that aRGB encompasses.

For me it;s simple. I display 99.9999% of mu y images for screen display. sRGB is therefore the best colourspace to stay with.(remembering that this is true for raw files)

IF you shoot in jpg only, then always use the best colour space you can, just in case you ever want to print high quality. Converting from aRGB to sRGB is usually more accurate than from sRGB to aRGB, in fact you'll get some very weird colourshift if you convert a bitmap image from sRGB to aRGB.

three easy steps to remember:

RAW -> makes no difference what you choose
aRGB.. if you shoot in jpg(or tiff) mode in camera for peace of mind
sRGB.. if you want easy of workflow and eliminate the need to convert for web or screen display

gje38752
18-11-2010, 12:04pm
Thanks so much for the info and the effort you put into providing it. Much appreciated:D