Color diference - DPChallenge Forums

04/23/2005 12:18:26 AM · #1

I know this has been discussed on other threads but i can't find it... if possible redirect me to one of thoses threads or just explain me why it is happening...
I treat my photos on photoshop and when i put them on the web it loses the colors a little bit.. I do save as for some sites and this was the cas on one of the photos... i recently change my proof setup to sRGB IEC61966-2.1 Those this have something to do with it. Before the proof setup was at working CMYK. Or is this the way i save it?

04/23/2005 12:29:20 AM · #2

The only way I have found to make all the colors everywhere the same is to work in RGB color and use Abode RGB (1998) color profile and do Save for web when saving.

04/23/2005 12:30:30 AM · #3

Originally posted by nico_blue:

The only way I have found to make all the colors everywhere the same is to work in RGB color and use Abode RGB (1998) color profile and do Save for web when saving.

But is this in proof setup?

04/23/2005 12:32:26 AM · #4

Forgote to add, there are two ways that i know off to convert a sRGB to Adobe RGB in PS...

If you are lacking color do Mode> Assign Profile
If you like how the picture looks then do Mode>Convert to Profile

Hope this helps...

04/23/2005 12:32:56 AM · #5

Originally posted by Discraft:

Originally posted by nico_blue:
The only way I have found to make all the colors everywhere the same is to work in RGB color and use Abode RGB (1998) color profile and do Save for web when saving.

But is this in proof setup?

What is proof setup?

Nikon AF Nikkor 50mm f/1.8D

04/23/2005 12:36:44 AM · #6

Originally posted by nico_blue:

Originally posted by Discraft:

Originally posted by nico_blue:
The only way I have found to make all the colors everywhere the same is to work in RGB color and use Abode RGB (1998) color profile and do Save for web when saving.

But is this in proof setup?

What is proof setup?

Go to view>proof setup.

David.C

04/23/2005 12:37:47 AM · #7

Originally posted by Discraft:

... I treat my photos on photoshop and when i put them on the web it loses the colors a little bit. ...

Just to clarify for my tired mind, do you mean when you look at them on the web the colors have change a bit compared to how the same file looks on your system? ... or do you mean the file that is uploaded does not look the same as it did before you saved as... ?

David

04/23/2005 12:40:55 AM · #8

Originally posted by Discraft:

Originally posted by nico_blue:

Originally posted by Discraft:

Originally posted by nico_blue:
The only way I have found to make all the colors everywhere the same is to work in RGB color and use Abode RGB (1998) color profile and do Save for web when saving.

But is this in proof setup?

What is proof setup?

Go to view>proof setup.

Ahhh, mine is on Working CYMK... but I doubt thats the problem, I think your problem is with sRGB vs RGB. Convert to RGB, do 'Save for web', upload to a challenge that hasnt started and compare what you have in PS to what you see. It should be the same.

04/23/2005 12:42:15 AM · #9

Originally posted by Britannica:

Originally posted by Discraft:
... I treat my photos on photoshop and when i put them on the web it loses the colors a little bit. ...

Just to clarify for my tired mind, do you mean when you look at them on the web the colors have change a bit compared to how the same file looks on your system? ... or do you mean the file that is uploaded does not look the same as it did before you saved as... ?

David

The problem is when i upload the image that i have on the system the colors are diferent from the sistem.

Nikon AF Nikkor 50mm f/1.8D

04/23/2005 12:43:30 AM · #10

Originally posted by nico_blue:

Originally posted by Discraft:

Originally posted by nico_blue:

Originally posted by Discraft:

Originally posted by nico_blue:
The only way I have found to make all the colors everywhere the same is to work in RGB color and use Abode RGB (1998) color profile and do Save for web when saving.

But is this in proof setup?

What is proof setup?

Go to view>proof setup.

Ahhh, mine is on Working CYMK... but I doubt thats the problem, I think your problem is with sRGB vs RGB. Convert to RGB, do 'Save for web', upload to a challenge that hasnt started and compare what you have in PS to what you see. It should be the same.

But it is in adobeRGB and the mode is on RGB too..

David.C

04/23/2005 06:42:51 AM · #11

Ok, let me make a stab at this.

The first thing to understand is the soft-proofing done in the view menu affects how the image is displayed -- But does not change the image!

How the image is viewed can be saved with the image as a color profile -- but unless the image is viewed in a color managed environment the color profile is ignored.

The second thing to understand is the web (and browsers in particular) are not color managed. That is, the browser will completely ignore any color management the image may have. I believe it has been said in other threads that DPC strips any color management and exif information from the image upon upload -- but I may be mistaken.

sRGB is the standardized default color space for the web, and has been adopted as semi-standard default color space for many other venues as well. It serves as a common ground between many different area, such as cameras, browsers, printers and so on.

AdobeRGB is Adobe's version of the RGB format and while it stores the color information in the same number format as sRGB it has a larger gamut of colors. This means the exact same numbers represent different colors based on which colorspace they are describing. This is true between all the different RGB variations.

When an AdobeRGB document is proofed as sRGB, PS translates the AdobeRGB values to the sRGB values for the same colors, or as close as it can get if the exact color is not available. This allows the user to see how the image will look once converted to sRGB -- but it does not actually convert the image. It's like looking thru a red filter; everything looks red, but the colors of the objects around you haven't changed.

By proofing an AdobeRGB image to sRGB and then 'save as'-ing with the sRGB profile (if I understand you correctly), PS is not changing the image into an sRGB image. It is still an AdobeRGB image, with AdobeRGB color values and a tag telling viewers to show it in the sRGB colorspace. But, when viewed in a meduim that is not color managed, the image is displayed in the viewers default colorspace (sRGB for browsers), which if you recall from above may not represent the same color with the values present. The end result is a shift in the color of the image.

To get past this, the image must actually be converted to the sRGB colorspace just prior to saving. This ways the values saved in the file are of the same colorspace the browsers are displaying it in. To do this you can use the Image/Mode/Convert to Profile... menu command or (I believe) the 'Save for Web...' option does the converting for you.

I find it easiest to set PS to work in sRGB all the time -- but that is because my camera outputs in sRGB and my main use is for the web. Your needs are probably quite different so use the working space that works best for you -- but keep in mind that every change in color space (actual changes, not proofing) looses a bit of color detail. So convert between them very sparingly.

Hopefully I haven't rambled too much. ;)

David

Marjo

Canon EOS-7D

Canon EF 70-200mm f/2.8L IS USM

04/23/2005 08:33:09 AM · #12

Britannica, This helps me. You've explained it very well. Thanks!