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Seesee
09-08-2008, 12:46am
Trying to get my head around CS3 atm coming from using Elements 5 for ages. Seems that since I have been using the D300 I have the colour space set to sRGB which is good, same as the D50 was, that's correct and fine:) When viewing and editing the images on the PC with CS3 they look fabulous { a little biased in my opinion maybe :rolleyes: }...but once uploaded onto the forum I am shocked at the loss of quality. There is, or was always a loss of a bit of IQ when I edited with Elements 5, but much more noticeable with CS3:confused:

I'm pretty sure I have the colour space in CS3 set to sRGB as well, but I'm starting to wonder :confused: ...If I'm looking in the correct section in CS3 then they are lots of options, lots and lots and I think I have it set to sRGB but maybe I'm looking in the wrong place ?

What i have done I think is under EDIT I have selected colour spaces and there's a lot of tweaks I dont understand

In the box I think I have it set to sRGB IEC61966-2.1.....I think

North American General Purpose etc etc heads the first selection in the box

plus there are all these other settings to choose from under headings like

CYMK
Gray
Spot Gain


and then under that is

COLOUR MANAGEMENT POLICIES ????????????

I'm really confused, can someone steer me in the right direction in regards to CS3 and settings tabs and try to remedy the los of quality when posting images here. I know this is a subject often brought up..butwhere in CS3 do I adjust for what I need :confused:

peterst6906
09-08-2008, 1:27am
In CS3, you can adjust your basic color settings under the Edit menu by going:

EDIT > COLOR SETTINGS (or just pressing Ctrl + Shift + K).

That will bring up a dialog box where you can set all your preferences. If you want your working RGB space to be sRGB, then the easiest thing to do is just select "North American General Purpose 2" from the first option box ("Settings").

That will automatically change the setting to this (including setting your RGB working space to sRGB):

http://peterstacey.com/images/forums/colorsettings.jpg

To explain what each of these areas is:

Working Spaces

This defines the different color spaces that you might use, depending on what mode you are in using Photoshop.

For example, if you were doing pre-press production to be output on a 4 color printing press, then you would probably at some point convert to CMYK and do editing and final output with the channels already separated ready for the press. In that case, the color space used in CMYK would be U.S. Web Coated (SWOP) v2.

In general, most people only need to worry about the RGB working space, so make sure this is set to sRGB (if that's what you want for your working space).

Many people use Adobe RGB for their working space and then convert to sRGB at the end. This can be useful if you are printing your own work on a good quality printer (then you don't convert it, you can just print it with the AdobeRGB and let the RIP/Driver handle the color conversion).

I personally use ProPhoto RGB, but it's not a space for everyone (some of it's colors lie outside human vision, so it's a colorspace that requires some experience). sRGB is good enough for most people, though you might also consider Adobe RGB down the road.

Color Management Policies

This is one to take particular note of (and also double check the color setting of your camera). Many people have their camera set to shoot in Adobe RGB and depending on what settings you have here, the camera setting may override your working space and you could be using something different to what you think.

For example, the basic setting for RGB is to 'preserve the embedded profile', so if you open an AdobeRGB tagged file from the camera, it will open in AdobeRGB, even if you have sRGB as your working space.

With the default setup, Photoshop won't tell you that and you'll be working away in AdobeRGB. When you then save the file and upload to the web, the colors will be less saturated and your image contrast will disappear.

The safest way to set this is to click all the boxes so that Photoshop will warn you of the profile mismatch and then you can decide to make the conversion when you open the file, or leave it alone and convert it later.

So just check the boxes and you should be fine (or set the option in the drop down to autmatically convert to the working space, that will also work).

Conversion Options

Adobe (ACE) is the default method used and is perfect. There's no need to change this unless you have a specific requirement.

In terms of intent, there are two options, relative colorimetric or perceptual. Either one is OK, but in general perceptual should cover most situations. With this set, whenever you convert the image to a new color profile, all of the colors will be shifted so that the relationship between them stays the same. This will preserve detail in saturated regions of the image.

This slightly changes the color numbers when you convert a file, but the end result will be that the image will look the same most of the time.

Relative colorimetric will shift the out of gamut colors into gamut when you convert from a large color space to a smaller one, but leave other colors alone. It's good in some situations.

You should generally always check "use black point compensation" and "use Dither".

Advanced Controls

Never touch these. My understanding is that Thomas Knoll added them as a bad joke and they live up to that reputation. They are bad to play around with. They will constantly make you push the colors into ridiculous positions and you won't even know until you print or output the image elsewhere.

-----

As another safe thing to do before saving your jpeg for display on the web is to go:

EDIT > CONVERT TO PROFILE

http://peterstacey.com/images/forums/colorsettings2.jpg

That will allow you one final check that you are in sRGB before you finally save the image. Under the options, if your file is not set to sRGB, you can select it from the drop-down box:

http://peterstacey.com/images/forums/colorsettings3.jpg

You need to make sure you use "convert to profile" and not "assign profile".

Hope that helps. This is a very quick introduction and there's more I could write about all the settings and different uses, but I don't want to confuse the more vlauable information with less useful stuff for day-to-day work. But if that didn't answer your questions or you have more, fire away.

Regards,

Peter

peterst6906
09-08-2008, 3:07am
Col,

Just some further information. I checked the embedded profile in both images in your Sun on the Sand (http://www.ausphotography.net.au/forum/showthread.php?t=15887) thread and they are tagged with AdobeRGB.

When I opened both files, I got this dialog box (which is for the first of your images):

http://peterstacey.com/images/forums/colorsettings4.jpg

I would almost bet that your color settings in camera are set to AdobeRGB and that in your color settings in Photoshop, under Color Management Policies, you haven't got "Ask when opening" checked next to 'Profile Mismatches'.

As a result, you have told Photoshop to override your color setting and use the image profile without warning you. So, Photoshop is using AdobeRGB encoding and then when you save the file out and upload it, you see a huge difference in quality because AdobeRGB is not a good match for the screen unless you are using color managed software.

Regards,

Peter

Seesee
09-08-2008, 12:22pm
Thankyou very much Peter, that's raised my level of understanding, appreciate your time to answer this, cheers mate.

dbax
09-08-2008, 1:00pm
Hey Rick,
I reckon this could go into the tutorial section with Peter's OK:)

TomAus
09-08-2008, 4:10pm
Col,

Just some further information. I checked the embedded profile in both images in your Sun on the Sand (http://www.ausphotography.net.au/forum/showthread.php?t=15887) thread and they are tagged with AdobeRGB.

When I opened both files, I got this dialog box (which is for the first of your images):

http://peterstacey.com/images/forums/colorsettings4.jpg

I would almost bet that your color settings in camera are set to AdobeRGB and that in your color settings in Photoshop, under Color Management Policies, you haven't got "Ask when opening" checked next to 'Profile Mismatches'.

As a result, you have told Photoshop to override your color setting and use the image profile without warning you. So, Photoshop is using AdobeRGB encoding and then when you save the file out and upload it, you see a huge difference in quality because AdobeRGB is not a good match for the screen unless you are using color managed software.

Regards,

Peter

Youve posted some great info here Peter. I had some colour issues that Rick helped out with the other day. But one thing I did do after seeing this other than try to remember this valuable information was to tick the "Ask when opening" check box 'Profile Mismatches'. So I opened a pic and it gave me the same warning. :confused: Checked my camera it is set to sRGB so thought PictureProject was converting when I transfered to computer. Found an option in the Transfer options dialouge, ticked "Embed ICC colour profile during transfer". Transferd a pick and in the main section of PictureProject in the options "Options" dialouge I changed the colour from NKsRGB to sRGB and ticked "use this instead of embeded profile"

So then I opend a photo and again PS had this warning. Had a bit more of a look and found that in Camera Raw 4.0 down the bottom the colour space was set to Adobe RGB :crzy: so changed that and no its workn...Wooohooo

So I thought Id share this info in case someone else is still getting a problem.

IanB
10-08-2008, 3:02pm
How do you get photoshop window into the forum page???

It may pay for everyone if you started a new thread to answer

Cheers

Roof
10-08-2008, 4:19pm
Alt+print screen - Is the active window screen dump, Then new in photoshop and choose in the preset Clipboard after that resize save as.... and attached to the post...

And Bob's your uncle....

Or get your hand on a little program called "SnagIt"

Hope this helps

ricktas
10-08-2008, 4:32pm
Yep, I use the alt + prntscrn method, then paste it into PS and save.

IanB
10-08-2008, 7:20pm
Thank for the replies, I will try it sometime. I use a laptop for emails and web stuff and another PC for photoshopping. I will need to the bring the PS page to the laptop. So much I don't know and so much more the learn.

Cheers

Big Pix
11-08-2008, 9:08am
here is a link to correct colour management.......

http://www.colourmanagement.co.nz/index.php

feral1
16-08-2008, 10:17pm
well done Peter, I think you have helped a lot of people how to get the correct profile they need for the web etc. me included.

Peter

peterst6906
17-08-2008, 5:52am
No problems Peter. It's a subject that can be confusing, but once you get your head around it, you shouldn't have any problems.

Regards,

Peter

DanNG
18-08-2008, 10:58pm
I highly recommend 'Color Management for Photographers By Andrew Rodney', fantastic book on the subject

peterst6906
18-08-2008, 11:06pm
I highly recommend 'Color Management for Photographers By Andrew Rodney', fantastic book on the subject

Yep. Andrew's book is very good. There is also a Bruce Fraser book that pre-dates Andrew's book and it is also a very good introduction to the subject.

Andrew's website also has good information freely available:

http://www.digitaldog.net/tips/index.shtml



Regards,

Peter