sRGB or AdobeRGB?
 

I've looked around, and can't find a really good Pro's/Con's for the two standards.

When should I use AdobeRGB ( with a 10D )?

Re: sRGB or AdobeRGB?
 

Take photos and process them in AdobeRGB. Print and web-display them in sRGB.

Re: sRGB or AdobeRGB?
 

Short and to the point... I love it...

Thanks Scottes.

I've also now found some other posts on this forum which give more info. That will teach me to do lazy searches :)

Re: sRGB or AdobeRGB?
 

http://www.shootsmarter.com/infocenter/wc025.html

google too ;)

http://www.google.com/search?hl=en&q...=Google+Search

Re: sRGB or AdobeRGB?
 

I use an Epson 2200 which has a color gamut larger then sRGB, so I shoot RAW with Adobe RGB selected( you can change your mind later in conversion), develop to Adobe RGB in Raw conversion, and print in Adobe RGB.
Most web applications are not color managed and your pictures will look washed out on the web unless you use sRGB.
Scott

Re: sRGB or AdobeRGB?
 

It sounds like selecting AdobeRGB on the camera gives you more options (greater colour range)... but you just need to convert it before saving for the web?

Re: sRGB or AdobeRGB?
 

Yes. When you want to put a file on the web, you usually do a few things. You downsize it, convert it to jpeg if it isn't, and convert it to sRGB. This is fairly easy to do. In PS go to File>Save for WEB . You make some selections about quality and size. I use Jpeg/medium and set my longest side to 800.
Scott

Re: sRGB or AdobeRGB?
 

Gotcha... Thanks

Re: sRGB or AdobeRGB?
 

Just as an added note, make sure to convert to sRGB before converting to JPEG with the "Save for WEB" command.

Re: sRGB or AdobeRGB?
 

I use the save for web command for all my web photos and never convert to sRGB before doing it. My photos on the web look like they should. When I open those photos up in PS, they no longer are recognized as Adobe RGB. Am I missing something?
Regards,
Scott

Re: sRGB or AdobeRGB?
 

Scott,
Try taking a photo in Adobe RGB with some strong cyans or purples and go to Save For Web. Check and uncheck the ICC check box. You should see the colors shift. I'd really wonder what was happening if they didn't - though it is possible that your image stays well within the gamuts of both ARGB & sRGB.

Re: sRGB or AdobeRGB?
 

I don't save it with the ICC profile(I leave the box unchecked) when I save for web. That must be why.
Regards,
scott

Re: sRGB or AdobeRGB?
 

Yes you are, Scott,the ICC profile. When you Save to Web without converting, the image is still in Adobe RGB, but the profile is not saved. So, when you go display the image on your screen, sRGB is assumed and changes the color of your image. The change may be subtle or very noticeable, depending on the colors in the image and saturation.

BTW, even if you save the image with the ICC profile checked, the image will still display on the web browser as if it were an sRGB image and possibly causing the colors to shift because the browser ignores the ICC profile saved with the image.

Re: sRGB or AdobeRGB?
 

Leo,

Scott does this, but he's saying that the colors *don't* shift. I don't understand how this is - whenever I do Save For Web on an AdobeRGB image I get color shifts, so I've learned to convert to sRGB and then do Save For Web. I'm confused why Scott doesn't see color shifts.

Re: sRGB or AdobeRGB?
 

That's a good question although with some images, it's hard to tell that there's been a color shift unless you are looking at the two images side by side.

Also, when you do a "Save for WEB", the actual image that was saved is not shown in PS so you really can't tell what the image looks like until you open it up to view it. The original image that the web image was saved from is not affected by the "Save for WEB" operation.

Re: sRGB or AdobeRGB?
 

Good point Leo.

Scott, try opening a TIFF of a bright colorful image. Do your processing, and then Save For Web as you usually do. Leave the TIFF open, and then open that JPG, and when it asks about a profile be sure to Assign it sRGB (since that's how people on the web will see it).

Do they look the same?

Re: sRGB or AdobeRGB?
 

I just reviewed the 16 bit tiffs and corresponding jpegs for web I shot for my Christmas 2004 gallery. They look identical. I tell PS to leave the jpeg images un color managed when I open them. Then, If I assign them sRGB they look dull. So, why is it that when I post them in PBASE or open them without color mgmt. do they look identical to the tiffs?
Scott

Re: sRGB or AdobeRGB?
 

That's a good question Scott. I really don't know why it works for you.

The top image was Adobe RGB, converted to sRGB, then Saved for Web, ICC unchecked.
The bottom image was Adobe RGB, no conversion done, then Saved for Web, ICC unchecked.

Re: sRGB or AdobeRGB?
 

This image demonstrates what happens when you view an Adobe RGB image in sRGB space. The original image was captured and processed in Adobe RGB.

The top is sRGB; Adobe RGB below


I chose this image because it has some intense cyans. However, you see the same type of difference with almost any image. Colors captured and edited in Adobe RGB space will look muted or somewhat desaturated when interpreted as (or viewed in) sRGB space. Thus, always convert from Adobe RGB to sRGB when preparing images for the web (which, in effect, interprets images as sRGB color numbers). With conversion, your image will look on the web very close to what you saw while editing in Photoshop.

It is important to understand that the different appearance is because the color numbers have different meanings in the two color spaces. Thus R=200,G=100,B=100 looks different in sRGB compared to Adobe RGB.

It is also true that Adobe RGB is a larger gamut color space than sRGB and thus requires a different set of RGB numbers (0 to 255) to specify colors - even those shared with sRGB.

Re: sRGB or AdobeRGB?
 

Scottes -

In your example, the correctly converted image (from Adobe RGB to sRGB) has more intense yellows and reds. The greens are slightly brighter. The sky is almost neutral - so you don't see a difference. (At least, that's what I see on my monitor.) All moderately to well saturated colors will be less vivid if they are not converted.

Do you see what I see?

Re: sRGB or AdobeRGB?
 

Scott, when I was viewing your Xmas images a couple of days ago, there was something about them that I just couldn't place my finger on. All the shots looked good, yet "different". Now I know what it is. I just downloaded two of your images (I hope you don't mind) and made 3 copies of each. I then loaded each one into PS. I assigned the first of the set a profile of Adobe RGB, the 2nd sRGB and the third as unmanaged.

The Adobe RGB and unmanaged pictures looked identical to each other. That's because by default, my PS working space is Adobe RGB. The sRGB ones were different but they looked exactly like what I see posted on PBase. But, when you compare the Adobe RGB pictures against the sRGB pictures, the Adobe RGB pictures look much more natural. The reds are bright as are the golds on the ribbon on the Xmas tree. In other words, they look more natural compared to the ones posted on the web.

I'll post a sample crop of the wall and the Xmas tree to illustrate the different (in another thread).

I'm now going to delete the pictures I downloaded in case you did mind and accept my apology.

Re: sRGB or AdobeRGB?
 

Right ... they should look dull when viewed in the wrong color space. That you already know. (sRGB captured images would look brighter if viewed in Adobe RGB space.)


Your PBASE images (beautiful!) are mounted against dark backgrounds, if I recall correctly. (PBase is having server problems - can't review them right now). Usually one edits in Photoshop against a neutral gray background. Your vision may be tricking you. Black backgrounds tend to make images "pop."

Re: sRGB or AdobeRGB?
 

Yes, that's exactly what I see. I couldn't find an image with any bright cyans.

OK, actually I was too lazy to find one...

Re: sRGB or AdobeRGB?
 

Here are the differences I was talking about:

Re: sRGB or AdobeRGB?
 

Scottes, Leo, Maderito, Thank you for your explanations. Leo, thank you for your efforts posting my images. I can't however tell the difference between the pictures you posted. I'm going to compare the images I have posted side by side with new ones made from the original tiffs made by converting to sRGB before saving for web. I'll get back to ya!
Have a Happy New Year,
Scott

Re: sRGB or AdobeRGB?
 

I redid all the pictures in my Christmas 2004 gallery by first saving to sRGB. Leo, Scottes, Maderito, you were all right. The new jpeg's are brighter and more colorful.
Thanks and Happy New Year,
Scott

Re: sRGB or AdobeRGB?
 

Can someone enlighten me how we do this conversion from Adobe 1998 to sRGB? I've noticed a color shift when I save for web as well...would be great if what I'm working on in Photoshop would show up exactly like that when I post it on the web.

Re: sRGB or AdobeRGB?
 

In Photoshop CS it's in the bottom of the Image / Adjustment menu. Can't check it right now because I don't have Photoshop here. Photoshop Elements does not have this feature.

Re: sRGB or AdobeRGB?
 

In Photoshop 6,7,CS: Image>Mode>Convert to Profile:

Source space: should say Adobe RGB if that's where you started
Destination space: choose sRGB

Options: Use ACE (doesn't really matter) conversion engine and check "black point compensation" and "dither". For intent, use "relative colometric" - although some suggest "perceptual".

Use the preview button. Your goal is to see minimal or no difference before and after the conversion. That's the point of the conversion: to map the color numbers from Adobe color space to equivalent numbers (or the best approximation) in sRGB color space.

When you finish, all the color numbers of your starting mage have been changed. You should save the converted file under a different name or in a different folder. Use "Save As" or "Save for Web." Optionally, you can attach the sRGB ICC profile while saving, although it's really not necessary when saving for web viewing.

Re: sRGB or AdobeRGB?
 

The above's really helpful.

In my 20D manual, they write:

"For normal images, sRGB is recommended."
and
"Adobe RGB... is mainly used for commercial printing and other industrial uses. This setting is not recommended if you do not know about image processing, Adobe RGB, and Design rule for Camera File System 2.0 (Exif 2.21). Since the image will look very subdued with sRGB personal computers and printers not compatible with Design rule for Camera File System 2.0 (Exif 2.21), post-processing of the image with software will be required."

Why do they make these statements?
Does it have anything to do with shooting in RAW vs JPG? Does shooting in Adobe RGB matter less for the latter?

Kevin.

Re: sRGB or AdobeRGB?
 

'scuse me guys.... Heady stuff, this conversion info. Scottes, I have PS set to Adobe RGB, and have just set my Canon S800 printer to Adobe RGB on Canon's advice, as the images were not printing as expected. Although I have yet to try the new setting, I am curious as to why you suggest that printing should be done in sRGB. I should explain, my printer was earlier set to "CNBJPRN" by default in colour management.
All in all, a very educational debate for those of us less familiar with the vexing issue of colour profiles and management issues. Not having ever posted images on the web, that aspect is totally new to me.
IainB

Re: sRGB or AdobeRGB?
 

I process my images in PSCS using Adobe RGB. I then convert to sRGB before I post the images up on the web. However, siince my printer, i9900, has a wider color gamut than sRGB provides for, I print all my images on it using the Adobe RGB color space. There are a lot of printers, however, tthat can only print using the sRGB color space. Images processed in Adobe RGB will have to converted to sRGB before they can be printed on these sRGB printers.

Re: sRGB or AdobeRGB?
 

Thanks PaceAce. Nicely explained! I look forward to achieving some better prints.
IainB

Re: sRGB or AdobeRGB?
 

Design rule for Camera File System (DCF) 2.0 and Exif 2.21 set standards for sharing and annotating image data transferred between different devices and applications (cameras, printers, Photoshop, etc.). The older standards centered on universal exchange of sRGB image data. The newer standard referred to in the 20D manual includes provisions for sRGB and Adobe RGB color space files.

The basic manual advice is good. Canon 10D/20D and 1 Series cameras can capture JPEGs in sRGB and Adobe RGB color spaces. If you don't want to bother with color management issues, use sRGB.

If you shoot RAW, you choose the color space (sRGB, Adobe RGB, ProPhoto RGB, etc) at the time of RAW conversion to JPEG or TIFF files during post processing. The embedded or associated JPEG captured with that same RAW image is in the color space set in the camera menu (sRGB or Adobe RGB).

Finallly, some Canon camera JPEG images may be recognized by Photoshop as "untagged" as if they don't have an associated color space. These are actually Adobe RGB files. Only Canon can explain and defend this apparent oddity.