Calibration for printing Vs web publishing?

[syd]

<p>Greetings all,</p>

<p>I am still very new to digital darkroom work and my question pertains to calibration of the home monitor. I understand that when we speak of Calibration we are generally doing this for the purpose of matching output for printing at home or for matching when sending work to external printers. Where does all of this intersect - if at all - with viewing for the web? Given that we have no control over how others have their own monitors set up - calibrated or no - how do we then go about calibrating our system for the best general viewing of our images online?<br>

<br /> # - Do you keep different monitor calibration settings ... one for printing and one for normal web viewing?</p>

<p># - If so, does that mean that you have two different versions of your images to suit optimum calibration settings? One version of an image Photoshop ready for the web to allow for the most general purpose online viewing, and one for printing set up with that in mind? Or am I missing something?</p>

<p>How do you solve the problem of the two different media requiring different treatment of your images and cater to both effectively? As an example - if I were to calibrate my monitor for printing there is no guarantee that others will have the same viewing of my images online as what I have at home ... how do you then calibrate for both web and printing and how does one solve the issue of needing different work flows for the same image depending on print or web?</p>

<p>Thanks, Simon.</p>

[Ed_Ingold]

<p>The monitor is calibrated so that images on the disk look correct, regardless of their ultimate disposition. A print profile (printer calibration) is used so that images on the disk look correct. The two are completely independent.</p>

<p>The problem with web display is that not everyone uses a calibrated monitor, or a color-managed program for that display. In general, sRGB is the best color space to for applications which don't recognize which color space is used (e.g., the web).</p>

[syd]

<p>____ The problem with web display is that not everyone uses a calibrated monitor, or a color-managed program for that display. ____</p>

<p>Yes, but further to that issue, doesn't monitor calibration also have as much to do with the values of brightness and contrast as colour? My problem here is in understanding how you get around the workflow for working images for web vs printing when the values of brightness and contrast are potentially so different on my monitor compared to what others are viewing online?</p>

<p>My question is simply ... if you calibrate your monitor and then edit your images in Photoshop and they look correct on your own monitor for web publishing ... what happens when you are dealing with a majority of the general public who are viewing your images at vastly different brightness and contrast settings? How does one compensate for this if you are a professional who uses their website as a means to selling their work or showing it in the best light? To me, my images might look great on the web because I have worked them after calibration of my monitor, but to Joe Smith they might be washed out or full of dark shadows because they are not using a calibrated system. What to do then?</p>

<p>I don't really get it ... it's not a question of colour space for me but rather one of brightness and contrast as much colour also.</p>

<p> </p>

[joe_c5]

<p>A separate monitor calibration might make sense if it had a different brightness and/or white balance to match the lighting in a viewing booth. Use two if you need two, otherwise a single monitor calibration is simpler.</p>

<p>The final images will probably need to be separate anyway for print versus the web, since they will have different resolutions. One can choose to edit them differently expecting different brightness and contrast ratios.</p>

<p>If the viewer is not using a calibrated monitor, then there is almost nothing one can do. At best, one could recommend that they use a calibrated monitor. So all people do is convert web images to sRGB color space, if they are not already in it. Most monitors are at least roughly similar to sRGB and at least roughly similar in brightness.</p>

[Ed_Ingold]

<p>You have no control over the vast majority of monitors which are uncalibrated. The best you can do is to publish sRGB images, in which the color space is truncated and contrasty. An image saved with a wider color space, like Adobe RGB, will tend to look flat and lifeless on a non-calibrated, non CMS computer.</p>

<p>The color space defines which combination of R, G and B are used for each color in the image file. A color-managed application like Photoshop reads the color space (if any) embedded in the image and reverse-engineers that specification so that images look essentially the same regardless of which color space is used.</p><div></div>

[pbarnes]

<p>I too ponder this issue Simon. And not knowing how to have two sets of settings that I could switch between, I have settled on setting my monitor for printing as that is more critical for me, and use soft proofing as well to deal with the reduced contrast and colour gamut of prints. For web images, I just make them as good as I can on my monitor, convert to sRGB and save with sharpening for screen.</p>

<p>I figure that as I have my screen at low brightness and low contrast (in an attempt to match printing paper in average lighting conditions) then my Web images will look will not look washed out or too dark on the average LCD screen likely to be set brighter than mine. But I am not sure about the logic of this approach...is my reasoning correct?</p>

[Ed_Ingold]

<p>If your monitor is calibrated, it is calibrated for all programs and viewers in Windows (or OS/X) since the profile is a system property. However, only a color-managed (CMS) program will read and interpret the embedded color space.</p>

<p>The example I posted is an sRGB image (I didn't take special precautions to mask the color space). If you want to see what it looks like in another color space (or no color space), open it in Photoshop and select the "Edit/Assign Color Space" dialog. Check the "Preview" box.</p>

<p>If you select "No Color Management", you will see what the file would look like in a non-CMS program like Internet Explorer. If you select the source color space (sRGB), you will see that there is no significant change in appearance. If you assign one of the color spaces (Prophoto RGB or Adobe RGB), you will see the panel labeled with that color space changes to look like the original sRGB panel (i.e., mostly normal).</p>

<p>To deactivate the monitor profile, go to the "Control Panel" window, select the "Display" applet and work your way through the tabs to the color management window and select another profile (e.g., the Windows default profile). Your homework assignment is to locate, disable and re-enable the calibration profile without the need to reboot. It's something you should know, and I've given a few hints without detailed instructions.</p>

[Ed_Ingold]

<p>The correct screen brightness depends on your editing environment. An LCD is typically calibrated to between 100 and 120 candelas (cd). I prefer to work in a room just bright enough to read (about 40 lumens), for which 120 cd gives me a good match with the printer.</p>

<p>My NEC P221W was 220 cd out of the box (max 300 cd). Some LCD monitors are much higher than that, but it might not matter if the user sits in an office environment (100 lumens). Don't worry about things you can't fix.</p>

[Ed_Ingold]

<p>Correction - lighting levels and standards are expressed as "foot-candles", not lumens, which are intensive and extensive parameters respectively.</p>