Color Space

[Don Thompson]

I am having problems with prints from a lab. They are suggesting that it could associated with my shooting in aRGB. I convert the files to sRGB in PS CS3 before uploading. This has been my workflow for some time and never had a problem, but they seem to think that is the problem.

What color space do you use, and have you ever heard of this being a problem?

Thanks for any help you might be able to provide.

[Alfred Forns]

Don if you shoot in RAW the space set in camera makes no difference since you can select sRBG or Adobe RGB during the conversion.

For printing you need to use Adobe RBG since it has a wider gamut. sRBG is used for posting, projecting etc. I suspect there is something else going on besides the color space. If you let us know the type of problem you are having maybe I can take a guess.

[Don Thompson]

The lab I use will only except sRGB so I must convert before uploading. I had the same understanding as what you say, that I can select the color space during conversion, but again, they say otherwise. They are encouraging me to shoot in sRGB but I hesitate to toss out the extra color information until I need to.

The problem is that my prints recently began having a color tint. I suspect that the problem began after calibrating my monitor, but I can't figure out what the problem might be. Also at their suggestion, I have tried using ICC profiles provided by the lab to soft proof my images, but have not been very happy with what I see on the monitor. The images are flat and muddy looking. Another thing that confuses me is that the images look fine on five different monitor, two calibrated, the rest not calibrated.

The lab is working with me try and solve the problem. They have asked me to shoot some pictures in aRGB and sRGB and send them the RAW and imbedded jpgs.

I would appreciate any suggestions. If it would be helpful, I could also post a picture or two here.

[john crookes]

Most labs can provide you with a profile for their product and you can convert to that and also soft proof the results in PS

[Roger Clark]

The lab I use will only except sRGB so I must convert before uploading.

The problem is that my prints recently began having a color tint. I suspect that the problem began after calibrating my monitor, but I can't figure out what the problem might be. Also at their suggestion, I have tried using ICC profiles provided by the lab to soft proof my images, but have not been very happy with what I see on the monitor. The images are flat and muddy looking. Another thing that confuses me is that the images look fine on five different monitor, two calibrated, the rest not calibrated.


Hi Don,

I use ICC profiles supplied by the lab I use, and for the specific paper I use (typically I do Fuji Crystal Archive paper on a lightjet).

In general, prints are CMYK (even when you submit RGB images). CRT and LCD monitors use RGB because they use light emission, and light adds. RGB is an additive color method. CMYK in print media is absorption (e.g. to get red, all violet, blue, green, yellow, etc light must be absorbed by the pigments). It is not uncommon for CMYK proofing to look dull compared to a saturated high contrast LCD monitor. But if you are using a properly calibrated monitor, the ICC profile and proofing should be showing you something close to the final print.

Roger

[Alfred Forns]

Don you are not throwing out any color information !!!!!!!!!!!!!!!

I have my camera set on sRGB since that is the best display for a monitor and it gives me a little safety in the histogram (narrower gamut) When the RAW image is processed my output is RGB.

Anyone arguing that it makes a difference (RGB vs sRGB) when shooting RAW I'm not sure I would like dealing with them?

As Roger pointed out the key is calibration !!! Curious to see what they come up with !!! Regarding the jpeg ... you only send the RAW file and the jepg will be there also which is one of the reasons we don't have to produce a RAW + jpeg !!!

[Don Thompson]

In general, prints are CMYK (even when you submit RGB images). It is not uncommon for CMYK proofing to look dull compared to a saturated high contrast LCD monitor. But if you are using a properly calibrated monitor, the ICC profile and proofing should be showing you something close to the final print.

Thanks for trying to help me understand all of this, but I can be pretty dense so you may have to hang with me awhile. Are you telling me that most likely the lab is using CMYK even if they require me to submit jpegs?



But if you are using a properly calibrated monitor, the ICC profile and proofing should be showing you something close to the final print.

I calibrate my monitor using a Eye-One by Gretag Macbeth so from what I have read, I assume that it would be doing a proper job of calibrating. Are you refering to the ICC profile generated by the calibration or the one supplied to me by the lab? I am using the profile generated by the calibration for processing the picture, but when I soft proof it, it is dull and flat.

[Don Thompson]

Don you are not throwing out any color information !!!!!!!!!!!!!!!

I have my camera set on sRGB since that is the best display for a monitor and it gives me a little safety in the histogram (narrower gamut) When the RAW image is processed my output is RGB.

Same disclaimer I gave Roger, so to make absolutely sure I understand what you are telling me, I can shoot RAW with the camera set to sRGB, yet when I process the RAW file should I need aRGB, I simply process it that way and all of the color information it still there?

[Roger Clark]

Thanks for trying to help me understand all of this, but I can be pretty dense so you may have to hang with me awhile. Are you telling me that most likely the lab is using CMYK even if they require me to submit jpegs?

Hi Don,
The lab is probably not using CMYK, but the printer must. Same as when you use an inkjet printer in your home. The inks are Cyan (C), Magenta (M), Yellow (Y), and black (K), thus CMYK (plus maybe some lighter versions of these). You feed the printer an RGB file, the printer converts it to CMYK to figure out the ink. I was trying to show that the different processes (emitted light of a computer monitor) versus the absorption process of a print (inkjet or photographic) are fundamentally different, and it is difficult to get the two to match. So when making a print, the process is CMYK, and that step can occur anywhere along the process, although with most modern printers (professional or consumer), the printer takes RGB and does the conversion to CMYK.

The proofing in photoshop (and probably other software) is converting to CMYK and trying to show what it will look like on the RGB monitor. As recently as 2003 I was required to submit CMYK files to a publisher. Just last month I had the option of RGB or CMYK. I previewed all the images in CMYK to be sure they looked ok, even though I did not have ICC profiles for the printer and delivered RGB files (a scientific journal).



I calibrate my monitor using a Eye-One by Gretag Macbeth so from what I have read, I assume that it would be doing a proper job of calibrating. Are you refering to the ICC profile generated by the calibration or the one supplied to me by the lab? I am using the profile generated by the calibration for processing the picture, but when I soft proof it, it is dull and flat.

I assume you are using an LCD. Even with calibration, (I'm using a spyder 3) I'm not happy with LCDs versus CRTs. The LCD is too saturated by the nature of the fluorescent lights: those lights have sharp emission lines that contribute to the saturated colors. New LCDs with LED lights should be much better.

With your calibrated monitor, do you have an inkjet printer? If you make a print and hold it up to the monitor, do the two images look the same (this is a tough comparison because you need a lot of light for the print). Usually the answer is no, they do not look the same. Now change the monitor view to proof mode. Do they look the same now? They should be very close, and if you use an ICC profile for the printer for the proof on the monitor, in theory they should match.

Some references:
on calibrating an LCD:
http://www.clarkvision.com/photoinfo/choosing_an_LCD_monitor/index.html

my digital work flow:
http://www.clarkvision.com/photoinfo/digitalworkflow/index.html

Roger

[Don Thompson]

So I need to increase the exposure, contrast etc until the image looks good in the proof mode, even if it looks over saturated and bright in edit mode?

[Don Lacy]

Try a different lab the problem might be on their end not yours. I highly recommend Aspen Creek Photo but there are other good ones online once you eliminate the lab as the problem then I would look into your work flow. Also do you know what kind of printer they are using.

[Sandra Nykerk]

Don, one way to test your lab's theory would be to shoot a few images in both Raw and Jpeg simultaneously. I don't know what camera you are using but most new cameras will allow you to do this. If the color space in your camera is set to sRGB, then the Jpegs will be in the sRGB color space, and you can set the color space to your preference when you are working on the Raw files in the raw converter. So then you can give the Jpegs to your lab, as well as the Raw files, which you have also converted to sRGB. This should satisfy the lab. But I would like to add that from what I have read of your workflow, this is their issue, not yours. Have they changed processors, a new machine, or anything else in their workflow, including a new operator? Have you tried a different lab to see if your prints are ok from a different provider?

Also, I would like to add that when you shoot Jpegs in-camera, the onboard software resident in the camera is converting your "raw" file from the unprocessed data to the jpeg file format and into the color space you have specified. Theoretically, the program, and algorithms, in a program like Photoshop are much more sophisticated than anything available in camera and your images processed from a Raw file and converted to sRGB should be "better" than those processed in-camera. I always bring my images from ACR into PSCS in Adobe RGB and then convert to sRGB if and when I need to. Which means to a lab or for the www. Otherwise, I leave the file in Adobe RGB and let my desktop printer RIP/software convert to CMYK.

Hope this helps.

[Roger Clark]

So I need to increase the exposure, contrast etc until the image looks good in the proof mode, even if it looks over saturated and bright in edit mode?

Yes, depending on the output device and it's color abilities. Example: next time you are in a bookstore, flip through the pages of some photo books. Sometimes I pick up a book and the color reproduction is terrible. That was a problem with the printing. If one had ICC profiles for proofing to that output, one could mitigate the color problems. Same with every printer, whether film (e.g. lightjet) or inkjet, always do the proofing and adjust colors to what you like. When I started my digital work flow, I had a series of prints made to see how the contrast and saturation settings I chose changed the output. You can start this process if you have a home inkjet. Try boosting contrast and/or color saturation until the proof looks similar to the RGB version, and then hopefully the print matches the proof. Or maybe its decrease contrast and boost saturation for your printer.

One thing to remember, LCD monitors have contrast of 1000:1, 2000:1, and more than 3000:1. Prints have less than 100:1, so it will never look exactly the same. You just want to establish methods to get you to "good enough" for your satisfaction.

Roger

[Don Thompson]

Thanks to everyone. I think I understand everything covered here, but now I am more confused than ever on whether or not I have PSCS3 setup correctly. I have noticed that in PS, under edit, color settings, that it doesn't indicate that the entire suite is synchronized, which I thought it should indicate if color management is properly setup.

[Michael Lloyd]

Don- My first thought when reading this was dump the lab. There are a lot of really good labs out there. I'm not sure about forum rules but I know of at least one pro lab that also offers consumer services. Even before I moved to a calibrated Eizo monitor I was getting good prints from them and I had no color space issues. Anything else I could add has already been covered.