what does the # in RGB/8# mean?
saltydog
Registered Users Posts: 243 Major grins
This has happened to me twice already, and I don't really understand, what is going on. I try to upload a pic to my Smugmug site and when it shows up, the colors are all messed up (e.g. with a tremendous red cast).
The photos are all jpgs, but the messed up ones show up in Photoshop as "RGB/8#", instead of RGB/8* as they usually do. I know what the RGB and the number 8 refer to, but the * or # is a mystery to me, and neither can I remember treating the "#" ones in any different way. To get my star back, I have to convert to CMYK, then back to RGB and suddenly all is well again.
Does anyone have an explanation for me? Thanks,
Jana
The photos are all jpgs, but the messed up ones show up in Photoshop as "RGB/8#", instead of RGB/8* as they usually do. I know what the RGB and the number 8 refer to, but the * or # is a mystery to me, and neither can I remember treating the "#" ones in any different way. To get my star back, I have to convert to CMYK, then back to RGB and suddenly all is well again.
Does anyone have an explanation for me? Thanks,
Jana
all that we see or seem
is but a dream within a dream
- Edgar Allan Poe
http://www.saltydogphotography.com
http://saltydogphotography.blogspot.com
is but a dream within a dream
- Edgar Allan Poe
http://www.saltydogphotography.com
http://saltydogphotography.blogspot.com
0
Comments
These two characters # or * refer to colour profiles (the third option is no character).
1) # = Document is non colour managed/does not contain an embedded ICC profile (your Working Space for the document colour mode will be used by default)
2) * = Image profile differs from your default Working Space set in Colour Settings (nothing to be concered with per se, if using version 6 or higher)
3) [blank, no character] = Image profile matches your default Working Space found in Colour Settings for the document colour mode
Hope this helps,
Stephen Marsh
http://members.ozemail.com.au/~binaryfx/
http://prepression.blogspot.com/
http://members.ozemail.com.au/~binaryfx/
http://prepression.blogspot.com/
What I still don't understand is that all the current files I am working on are showing up as RGB/8* (you're correct, there's that 3rd option with no character behind the 8), although both my camera profile and Photoshop (version CS2) are set to Adobe RGB. I just double-checked and the color settings are indeed correct. This occurs only with pics taken by my new Nikon D300, everything from my old D70 shows up without any symbols at all .
is but a dream within a dream
- Edgar Allan Poe
http://www.saltydogphotography.com
http://saltydogphotography.blogspot.com
I have been told to never "convert" to a profile....always assign the profile....I was told it could cause justthis color shifting your having.....and I and the person(s) whome told me could be dead wrong also....:D
??? Hmmm..... : |
!!! Aaaah : )
Sincerely,
Stephen Marsh
http://members.ozemail.com.au/~binaryfx/
http://prepression.blogspot.com/
http://members.ozemail.com.au/~binaryfx/
http://prepression.blogspot.com/
They both have their places. Convert actually changes the space. Assign only "labels" it. So if you have an image with no profile, you must assign the right one so that the next app make the correct assumption about its colors. For example if an image was edited as Adobe RGB and there is no profile, assigning sRGB will cause a horrendous shift because it's been mis-labeled as sRGB when its very nature as Adobe RGB has not changed. If it's Adobe RGB and you want it to be sRGB for the Web, you must convert, not assign, so that it actually becomes sRGB and not merely mis-labeled as such.
(Kind of reminds me of this news story. Taking a pile of CDs of Mexican pop music and "assigning" them as Cisco firewall configuration software does not actually change the content of the discs. )
This is exactly backwards. I think you're just remembering it backwards. Use Convert to Profile. Do not use Assign to Profile.
Convert to profile is what you should be using when you want to preserve the existing look and colors of your document (or as many as will fit in the gamut of your chosen colorspace), but change the colorspace of your document. So, if you have an AdobeRGB image out of your camera and you want to post an sRGB version of that to the web, you should use Convert to Profile to convert it to sRGB.
Except in cases of a damaged image and certain exotic and advanced techniques for doing image correction, you should never use assign profile. Assign to profile causes a color shift everytime you use it. It is supposed to cause a color shift.
Only read further here if you want to know what the technical difference is betwen these two commands. You don't have to understand this to know that you should be using Convert to Profile. Anyway, here goes...
When a color-managed application (like Photoshop, Safari, Lightroom, etc...) displays an image, it reads the individual numbers in the image (the red values, the green values and the blue values), then looks at what color palette those numbers are to be interpreted with (that's the colorspace of the document) and it then looks at the color palette of the display device (that's your monitor profile). For a given RGB value (let's pick a reddish tone like 200,40,0), it says OK, I have an RGB value (200,40,0). Those numbers are supposed to apply to the sRGB colorspace. OK, since sRGB is an international standard that means I now know with consistency from one computer to the next exactly what color that should be and how it should look. OK, now I want to render that color on the monitor. OK, I go look at the monitor profile and I find out what kinds of numbers I need to send to the monitor in order for it to display the sRGB standard color of (200,40,0). I send those numbers to the monitor and if the monitor profile was accurate, I get the perfect standard color that I was expecting.
If I now take that same original document and "assign profile" to AdobeRGB, the numbers in the image stay the same, but the image is now labeled as AdobeRGB. Now, when a color-managed application goes to display that image, it loads up the same pixel values of (200,40,0) and says OK, this is supposed to be the AdobeRGB international standard value for (200,40,0). That is a significantly different color than the sRGB standard for that value. It is, in fact, a less saturated, less red color. The app then goes through the same process as above with the monitor profile and when the color ends up on the monitor is is less saturated and less red than in the first scenario. There has been a big color shift in the image.
If I now take that same original document and "convert to profile" to AdobeRGB, the conversion process converts all the numbers in the image so that (200,40,0) in sRGB is replaced with the numbers in AdobeRGB that render the same color (or as close as possible) - let's say they would be (215, 43,0). The numbers are changed. The image is now labeled as AdobeRGB. When the color-managed software goes to display this document, it goes through the same process as above, but when the color comes out on the screen, it comes out the same as scenario #1. The color of the original image has been preserved.
Someone once used the analogy of different languages. If you have a sentence written in English and you get someone who only knows English, the whole thing makes sense.
Likewise, if you translate that sentence into Spanish and get someone who only speaks Spanish, the whole thing make sense.
But, if you take the English sentence and give it to someone who only speaks Spanish and tell them it's Spanish, they either won't understand it or will misunderstand it.
The legitimate uses for "Assign to Profile" are not very common for most people. The most obvious legitimate use is when an image is known the have an inaccurate or missing profile. In that case, you just want to "fix" the metadata and properly label the image. You have to "know" what the correct value for the numbers in the image is supposed to be and you can use Assign to Profile to label it properly. In the analogy above, this would be like the Spanish speaker saying, this isn't Spanish - you need to label this as English and go get an English speaker. The other uses I know of are to do some fairly exotic transformations (either color or luminosity) on an image. I personally find it easier to accomplish these same correctinos using more conventional tools (curves and other Photoshop controls), but there are some who like to use profiles.
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Well since I can remember Woodstock, I can't blame my memory on that..........and yes you are correct, I had it bass ackwards.....You saved me again Johnbowbow
Thanks! FWIW, this thread just helped me today. I ordered some greeting card paper and the company provided a landscape and portrait template for Photoshop to facilitate printing. The portrait template drastically changed the color of my photo. The ONLY thing I found different was the # vs the *. Sure enough, after looking at the file info, a profile was not assigned to the portrait template. I assigned the same profile as found in the landscape template, and it fixed the issue.