SRGB colour.

[Willy wombat]

Who uses the SRGB colour profile when posting pictures on the net?

I just got a tip from someone to use it. I had been using RGB 1998 as my default.

What do you guys think about it? I understand that if i want to print my pictures out i should not use SRGB but SRGB is the best for the net.

Another question - should i process in RGB 1998 and then convert to SRGB at the end or does it make no difference?

[Hlop]

Hi Willy,

I noticed that images with AdobeRGB profile look bit darker and dull on the web. So, I'm shooting and PPing with AdobeRGB and the last set of images I posted to the web was converted to sRGB. They look more vivid but somehow less natural. Now, I doubt myself what should I do next time ....

I might try to do both AdobeRGB and sRGB and post them to compare side by side. Most probably tomorrow

[DaveB]

The official web standards say that images are expected to be in the sRGB colour space.
In reality hardly any web browsers do colour management and convert it to the profile of your display, so you're stuck with trying to find a colour space which is a good approximation for the average monitor out there being used to look at your web pages. Luckily this was one of the design goals of sRGB so it's your best hope.

If you don't convert your images to sRGB they will look subtly different to what you would expect (but in the end sRGB is not an *exact* match for everyones' screens so it's a crap shoot anyway). To see the effect of not converting your image, in Photoshop try previewing the effect of assigning sRGB to the image.

should i process in RGB 1998 and then convert to SRGB at the end or does it make no difference

A common workflow is to process the image (colour casts, cloning out dust, etc, etc) to produce a master version at full resolution, and then produce downsized and sharpened copies for various uses (e.g. prints, web) from that master. If your master is in sRGB then you won't be able to take advantage of the wider gamuts of some output devices, even if a colour in the original was more vibrant than would fit in sRGB (and most dSLR sensors can capture a wider range of colours than will fit in sRGB).
I think most "serious" photographers use larger colour spaces (mostly AdobeRGB 1998) as it lets them take better advantage of the gamut of various devices without restricting their images to a specific gamut from the start.

Mostly I use AdobeRGB 1998 as my workspace, but my workflow for generating web images involves a Convert to Profile (sRGB) step, just as my workflow for prints involves converting to the printer's profile.

Did I mention I conduct Colour Management training?

[stubbsy]

No question sRGB is right for the web. I had a fairly detailed post on this which you might like to track down when the forum is back up fully. Here are three comparison shots I used in that link. First is using sRGB, second is adobe RGB and thrid is using a wider Nikon gamut (nkWide). The difference can be startling - especially in the third image. I have my camera set to adobe rgb and in PP convert to sRGB for web posting. On the PC both images look the same, but in a web browser....







Edit: Updated to add middle image in adobe rgb

[sheepie]

Peter - for someone who claims to know nothing, your efforts here are very much appreciated!
The difference here is astounding - I knew about the requirement to convert to rgb, but was never really aware of the huge difference it could mean in web browsing.

I'll be looking for your full article once the database is back

Thanks

[kipper]

Sigh. Can't believe people are still asking this question

sRGB - web
aRGB - postprocessing

Also if you're using photoshop, use the CONVERT TO COLOR PROFILE tool. This will map from aRGB space to sRGB, not using this will result in color variations. Then use SAVE FOR THE WEB, not doing this will also result in color variations. These aren't my own words but taken from a tutorial on the web. I've tried doing with and without and have noticed the effects, hence why I went searching for how to do it in the first place.

Tip, make an action to convert to sRGB and save for the web. It saves time.

[Hlop]

Hi Peter,

Could you post AdobeRGB image as well? It should make more sense then posting some gamut no one realy uses In our case you're shooting in Adobe RGB and then you might convert image to sRGB before posting to the web or leave it as is. Here is the point where difference might appear

[avkomp]

so kipper,

for us dummies new to the whole digital thingy

we set the camera to srgb colour but convert to adobe rgb for post processing etc

and finally to srgb for posting to the web??
Is this the definitive method??

dont suppose you have the link to the tutorial you mentioned?

I still gotta get a full handle on obtaining the best final results.

Steve

[DaveB]

we set the camera to srgb colour but convert to adobe rgb for post processing etc

and finally to srgb for posting to the web??
Is this the definitive method??

If you're going to do that, you may as well keep the image in sRGB for post processing.

If you're shooting in JPEG, you can set the camera to AdobeRGB, keep the image in AdobeRGB for processing, and convert to sRGB as required for output.

If you're shooting in RAW, you can process the image from RAW directly into AdobeRGB (or whatever profile you want - depending on your RAW converter) for processing. Whether your camera is set to sRGB or AdobeRGB only affects camera-generated JPEGs or TIFFs.

dont suppose you have the link to the tutorial you mentioned?

It's apparently in the old forum threads that are being restored from backup after the hack...

[kipper]

Here's how I look at it.

If you're shooting JPEG there is probably a reason eg. not wanting to postprocess much. So if you're shooting JPEG, stick to the color space you're aiming at publishing on. For instance web, stick to sRGB if shooting JPEG.

Now here is what I do:

If you're shooting RAW, I leave mine on aRGB. Even though it doesn't matter because I can change it in NC, I prefer to leave it that way as it requires one less step in my workflow. I work in aRGB as I know I will be doing postprocessing eg. cropping, cloning and level corrections etc.

I always keep a PSD (although recently I haven't bothered as I'm going to do a major overhaul and remove all of the stuff I've processed so far and redo it) without framing (my frames are actions).

So then I use my actions to add a frame.

Once I'm ready to publish for the web, I use the CONVERT TO COLOR PROFILE tool and select sRGB. This will map from aRGB to sRGB.

Then once this is done, SAVE FOR THE WEB. Select JPEG, set the quality (check what filesize it will produce down the bottom of the dialog it should tell you). Then click save.

Now you should be ready to upload a JPEG that looks 99.9% accurate to the aRGB one.

[avkomp]

thanks for that,

think thats pretty much what I am doing.
I must just have dud pix to start with!!

Steve

[Deano]

Then once this is done, SAVE FOR THE WEB. Select JPEG, set the quality (check what filesize it will produce down the bottom of the dialog it should tell you). Then click save.

Master Kipper,

Why Save For Web and not Save As JPEG? I find save for web doesn't include exif info. PBase will extract the exif if it exists and therefore I always use Save As.

Grasshopper Deano

[Onyx]

http://www.photomigrations.com/articles/0409400.htm

There was also a photoshop tutorial based site that posted the damming difference in colour between aRGB and sRGB display (as Stubbsy has illustrated above) but I can't find the link now.

[kipper]

Well Deano, it was because I found Save as Jpeg still had some color inconsistacies and while the Save for Web didn't. I was doing the same as you until I read a tutorial on how to make sure the colors look the same on the web as you seem the in PS.

I'll take a look into it again this weekend. At the moment I'm a bit exhausted.

[DaveB]

Both SaveForWeb and SaveAsJPEG give you the option of including the current profile in the JPEG. I've heard some people claim that SaveForWeb somehow converts the colours for you - this is not true. More on this later.

SaveAsJPEG leaves all the metadata in the image. This includes XMP, EXIF, IPTC, and more. If you're on a Mac it may also put data in the file's resource fork (once you copy the file to a web server this will disappear). It gives you 12 levels of JPEG compression.

SaveForWeb strips out all the metadata. If you're producing lots of images for web pages then you don't want to include extra kilobytes with each thumbnail (this is the same reason why we typically don't embed the sRGB profile in web images: it's the assumed source anyway). It gives you 100 levels of JPEG compression (and even lets you specify a filesize and it will find the best quality that will fit in that size). It can do funky things like using masks to specify different quality levels for different parts of the image (but not many people use this).

I think where some people's misconceptions about SaveForWeb's handling of colours comes from is the fact that when it shows you a preview of the result it does it with colour management turned off. That is, the image is assumed to be in your monitor's colour space, just as it would be in most web browsers. So, if you have an sRGB image and use SaveForWeb, the preview (and the result in your web browser) may look slightly different from the way Photoshop showed it. This is simply because your monitor is not a perfect match for sRGB. If you used SaveAsJPEG you would get the same result once your image made it to the web browser.

SaveForWeb is a convenient and efficient means of generating web graphics. But if you want to preserve metadata such as EXIF you'll have to use SaveAsJPEG. The colour results will be the same (for web graphics you should do an explicit Convert To sRGB whichever you use).

[Deano]

Excellent explaination.

Thanks Dave.

Cheers
Dean

[stubbsy]

Hi Peter,

Could you post AdobeRGB image as well? It should make more sense then posting some gamut no one realy uses In our case you're shooting in Adobe RGB and then you might convert image to sRGB before posting to the web or leave it as is. Here is the point where difference might appear

Updated post to add a middle image in adobe RGB

[mudder]

Wow, thanks for that comparison Peter, really shows how significant the difference can really be, I would never have expected that much diff, I'm really surprised... Thanks...

[Willy wombat]

I meant to say thanks for all the info provided in this post before the hack, but didnt get a chance. So belated thanks guys. Great info.