RGB question

[dsp921]

Is it necessary to switch my photos to sRGB when i convert it to facebook size and 72 ppi when I upload it to facebook? Or shall I keep it at aRGB?

For the web use sRGB, many browsers are not colorspace aware and will revert to sRGB. That can cause colors to be way off. Safari and some others know about colorspace, but at this point it is best to be safe and stick with sRGB.
As a side note, some print labs (like Mpix) still want sRGB. So, when in doubt use sRGB. If you know your printer is capable go with aRGB.

 

[clanthar]

now i know why the colors were different. the setting in pse 9 is argb, but i checked my camera and it was srgb. thanks again though guys, i learned a bunch through this thread.

That's not why the colors you saw were different. This thread is very confused and full of misinformation.

You need to read about RGB color spaces. The problem you had involves moving your photo from a color managed environment to a non-color managed environment.

Joe

 

[dsp921]

thanks for the responses guys. i will probably be editing in lightroom 3, so should i keep my monitor and camera on adobe rgb, and lightroom on its own color setting, or switch it to adobe?

Your best bet is to keep everything in the same colorspace. I use aRGB everywhere, except when I save as jpeg for uploading to the web. If you use multiple colorspaces in your workflow things could get confusing.

 

[Robin Usagani]

thanks for the responses guys. i will probably be editing in lightroom 3, so should i keep my monitor and camera on adobe rgb, and lightroom on its own color setting, or switch it to adobe?

Your best bet is to keep everything in the same colorspace. I use aRGB everywhere, except when I save as jpeg for uploading to the web. If you use multiple colorspaces in your workflow things could get confusing.

This is what Ive been doing. Thx!

 

[JacobGriz]

how can i get it to match my printer well? if i (epson stylus cx4200) when i set it on adobe rgb, its way too dark, so i put it on the highest lowest gamma (1.5) and it was a little better, then contrast to -25, but still not right. should i set it to no color management?

 

[clanthar]

ok so this whole rgb has confused me to no end. Adobe RGB or sRGB? i want to print my own pics, but i also want to upload them online. Also, when using photoshop, should i change the RGB there, or change it on my monitor. When I change the RGB in photoshop, i dont see the image change what so ever. Then, when i change it on my monitor, i dont see a change either.

Let's back up.

First, how exactly are you changing color spaces on your monitor since that's impossible?

The problem you've had with the changing appearance of your photos has nothing to do with the differences between Adobe RGB and sRGB. As you noted, when you change the color space in Photoshop your photo doesn't change. Here's an illustration of what you're experiencing:

This is a screen shot of my computer. On the left is the photo open in Photoshop. On the right is the same photo open in Picasa. Photoshop is correctly displaying the photo. It's doing two critical things. 1. It's processing the RGB values in the photo using the embedded ICC profile in the file that identifies the color space. 2. It is displaying the photo using the ICC profile for my monitor that was created using xRite's i1 color match system. Picasa isn't doing either of those things. As a result Picasa has trashed my photo. NOTE: Picasa trashes all photos all the time.

Most photo editing software and most software that displays photos on computers trashes the photos. Yikes! Here's why:

Your photos are RGB raster image files. Every pixel in your photo is identified by three numbers. There's a R(ed) number, a G(reen) number and a B(lue) number. So for example this color:

(Blue sky) has the number values R = 170, G = 206 and B = 247 in the Adobe 1998 color space. It is meaningless to identify those RGB values without simultaneously identifying the color space. Because in a different color space that exact color will have different number values. In the sRGB color space that color is R = 154, G = 207 and B = 249.

Digital photo files have an embedded ICC profile that identifies the referenced color space. It is essential that they have this. They have been trashed if it's removed. If you save a photo in Picasa it removes the ICC profile, as do lots of other consumer market software programs. Using the photo's embedded profile is a feature of a color managed workflow. For color management to work you can't break the workflow. You've been breaking the workflow.

This isn't about one color space being better than the other or one is for photographers and another is for everyone else. Different color spaces exist to support different applications. As you noted, good color manged software can convert between color spaces without altering the photo --i.e. Photoshop.

Adobe RGB versus sRGB:
Adobe RGB has a slightly larger overall gamut (range) especially into the greens so that light greens, light cyans and some yellows are available in the Adobe RGB color space that are not available in sRGB. Note that I used the word "slightly." MORE ISN'T ALWAYS BETTER. This isn't about better and worse. The Adobe RGB color gamut is larger (more supported colors) than 90+% of all the computer monitors in use out there. There are monitors that can support the Adobe RGB color space -- Here's one: EIZO / ColorEdge Hardware Calibration Monitors Make sure you look up the price. Reality is that many contemporary monitors can't display the sRGB gamut -- like yours (laptops).

So when you hear a photographer say, "I work exclusively in Adobe RGB because I need more color." What they're probably saying is, "I work in Adobe RGB so I can have colors in my photos that I can't actually see -- woah! invisible colors, way cool!"

Adobe RGB was developed to support the professional press industry. Read "press" as people who make prints on big multi-million dollar offset machines. sRGB was developed to support modern computer display equipment like the LCD monitors down the street at Worst Buy -- like the stuff most of us are probably using. And that also then means the Internet. (Before putting the two above photos into this post I made sure they were sRGB). To avoid surprises, use the color space that best supports what you're doing. Here's a point of confusion: you'll find some people say that sRGB is best for the web since the Internet is sRGB. Yes, sRGB is best for the web, but not because the Internet is sRGB. Many people using the Internet use software to view photos that doesn't process the photo's ICC profile (Picasa), like Internet Explorer. Since sRGB was designed to support computer displays and most computer display makers now work to make their hardware sRGB compatible an sRGB color space photo is less likely to change when it's being trashed by someone using IE or Chrome or some other cra*p software. A photo with an embedded profile in the Adobe RGB color space will display just fine on a MAC with a calibrated display running Safari or any computer with a calibrated display running Firefox.

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You're also having a printing problem -- again you have a broken workflow. The problem isn't what color space you're using. The problem is you don't have a way to translate the RGB values in your files to the printer. To color manage the print output you really need to have a printer/paper ICC profile available for Photoshop to use so it can correctly map your photo's colors to the printer. In your case that's going to be harder to get because of the model printer you're using. Your best option is to be sure and use the paper and inks made by the printer manufacturer. If you want to spend the $$ you can have a custom profile created for you: Custom ICC and ICM Printer Profiles

Take Care,
Joe

 

[Robin Usagani]

Nice Joe!

 

[JacobGriz]

thanks joe, that was extremely helpful. i set the screen profile and printer profile to adobe rgb.