Calibration. Kent Messamore 7/23/2013. JKM 7/23/2013 Enhanced Images 1

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1 Calibration Kent Messamore 7/23/2013 JKM 7/23/2013 Enhanced Images 1

2 Predictable Consistent Results? How do you calibrate your camera? Auto White Balance in camera is inconsistent Amateur takes a single photograph and is satisfied Professional takes multiples and they should match If you desire professional status you should demand Predictable Consistent Results Predictable Consistent Results requires Color Management Color Management has been available since Photoshop 5.5 on both MAC and PC JKM 7/23/2013 Enhanced Images 2

3 How do we see color? Your camera cannot capture all of the colors that you can see. (Try capturing a fall tree in the sunlight). There are some colors that your camera can capture that you can t see, (camera mfgs filter out infrared) The limited range of colors of your camera is called a Color Space or a Gamut JKM 7/23/2013 Enhanced Images 3

4 Why do we need Color Management? Each device on your system, Computer Software application, Monitor, Printer, Scanner, Camera, etc. displays color differently. CRTs are quite different than LCDs Printers from different mfgs print color differently Printers print on matte paper differently than glossy paper. Monitors & Printers even use different color models A Color Management system attempts to match all of these devices to standard color space called the Profile Connection Space (PCS) JKM 7/23/2013 Enhanced Images 4

5 Color Management Ensuring that each device on your system is calibrated to an industry standard color space as defined by the International Color Consortium (ICC) This is done by creating a transforming profile for each device by which differences from the standard color space can be minimized This allows a document to be scanned into your system, viewed on your monitor, and printed, so that the input document and the output document visually compare. The standard color space is called PCS (Profile Connection Space) Kodak Q60 Reflective Scanner Target JKM 7/23/2013 Enhanced Images 5

6 Color Models RGB - Additive Color CMYK Subtractive Color RED R+B=M B+G=C R+G=Y Cyan C Ink + Y Ink = G Y Ink + M Ink = R M Ink + C Ink = B C+Y+M = Brown K = black Ink added RED K Green Blue Magenta Yellow JKM 7/23/2013 Enhanced Images 6

7 Color Gamut Commission Internationale de l Eclairage (CIE) Gamut is like a box of crayons How many crayons are in your Camera s box? JKM 7/23/2013 Enhanced Images 7

8 Color Gamut Working Space Working Space is the Gamut inside Photoshop In order of how many crayons are in the box: srgb Optimized for Web ColorMatch Optimized for Printer (old color space) Adobe RGB (1998) ProPhoto Big box of crayons Recommend Adobe RGB (1998) or ProPhoto if you are more experienced JKM 7/23/2013 Enhanced Images 8

9 Monitor Calibration Same picture but Monitor Gamma has been changed. You can t edit what you can t see. Most important thing you can do to improve your pictures! JKM 7/23/2013 Enhanced Images 9

10 calibrate Monitor & create Monitor Profile Profile Connection Space JKM 7/23/2013 Enhanced Images 10

11 Monitor Calibration- calorimeters Spyder 3 CRTs LCDs Projectors $202 CRTs LCDs $138 XRite Eye One CRTs LCDs Projectors $206 CRTs LCDs $149 JKM 7/23/2013 Enhanced Images 11

12 Adjustment parameters Targets for Prepress Gamma 2.2 White Point 5000 Luminance 125 cd/m2 Targets for Photo image editing Gamma 2.2 White Point 5800 Luminance 125 cd/m2 JKM 7/23/2013 Enhanced Images 12

13 Test Target Check for brightness Is it comfortable to your eyes Check range of grays You should see every step of gray scale Check midtone gray = You should see no color cast Check Black and White Check shadows for detail Check highlights Check skin tones Check GretagMacbeth Color Checker Red 203, 0, 0 Green 64, 173, 38 Blue 0, 0, 142 Cyan o, 148, 189 Magenta 207, 3, 124 Yellow 255, 217, 0 Black 0, 0, 0 JKM 7/23/2013 Enhanced Images 13

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15 Profile must be created for combination of Printer and paper Calibrated?? JKM 7/23/2013 Enhanced Images 15

16 Printer Profiles - Free Print Manufacturers Paper Manufacturers Paper Sellers Loading Profiles: Once Downloaded, profiles are placed into the Windows operating system at C:\WINDOWS\SYSTEM32\SPOOL\DRIVERS\COLOR JKM 7/23/2013 Enhanced Images 16

17 Printer Profiles Imageprint RIP - $495-$ m#prices Colorburst RIP - $495 - $ Spyder 3 - $600 XRite Color Munki - $450 ($100 rebate) JKM 7/23/2013 Enhanced Images 17

18 What if my printer doesn t support profiles? Live with it or Get a printer that does or Make your own JKM 7/23/2013 Enhanced Images 18

19 What if I use Wal-Mart or Costco? Make sure your monitor is calibrated If your prints come back too dark You are probably using an LCD which tends to be much brighter than CRTs Compare paper used against LCD white. If no match, the print will never match. Check with your vendor/manual on how to change the LCD brightness (on my laptop Fn and up/down arrows control brightness) Brightness should be around 90 cd/m2 which is closer to the brightness level of a typical CRT. Is your Lab using cheap paper? Is your Lab using ICC profiles? In Photoshop you can embed the lab s ICC profile into the image prior to sending it to the lab Edit ->Convert to Profile -> Destination Space drop down. If not should you try another Lab? JKM 7/23/2013 Enhanced Images 19

20 Photoshop Color Settings Photoshop Default For Color Management JKM 7/23/2013 Enhanced Images 20

21 Check Proof Colors & Gamut Warning Soft Proofing Proof Setup -> Custom Select Printer/Paper Profile How Photoshop handles Out of Gamut colors use either Perceptual or Relative. Your personal preference JKM 7/23/2013 Enhanced Images 21

22 Rendering Intent (How to handle out of Gamut colors) Perceptual Gamut of image is compressed until within gamut of destination color space. Advantage is it keeps relationships between colors within the image. Colors may change. Can be relied on for reasonable quality Relative Colorimetric Leaves in gamut colors same; colors out of gamut are mapped to nearest 'in gamut' Clips out of gamut colors Black & White points remapped to new color space, keeping gray s gray. Provide higher quality images than Perceptual, but can create banding, particularly in blue skies First choice for Photographic images. Absolute Colorimetric Similar to Relative Colorimetric except Black & White Points not remapped. Good when a particular trademarked color must be retained Not recommended Saturation Preserves saturation of 'out of gamut' colors at expense of inaccurate hue and lightness Used in business graphics where saturated colors are more important than color accuracy. Not Recommended JKM 7/23/2013 Enhanced Images 22

23 Print with Preview -Let Photoshop manage colors -Insert Printer Profile -Insert intent -Print JKM 7/23/2013 Enhanced Images 23

24 Printer/Paper Setup Select Printer Select Paper Select Image Color Management (ICM) Extremely important: Select No color Adjustment. You are telling the Printer not to color manage the image because Photoshop is doing the management. JKM 7/23/2013 Enhanced Images 24

25 Print with Preview Dialog Click Print Print with Preview is for paper positioning verification only. Do not pay attention to the colors in the image. They may look terrible JKM 7/23/2013 Enhanced Images 25

26 Good Sources for understanding Color Management Understanding Digital Color by Green. Basic to intermediate level book, directed at the pre-press and printing industries but which covers a lot of the issues of managing color for any industry using digital images. Digital Color Management by Giorgianni and Madden. Discusses many of the theoretical issues involved in color management. Color Management for Printing and Publishing by Johnson (Pira International). Relatively advanced, in-depth description of many fundamental color management topics. Real World Color Management by Fraser, Bunting and Murphy Understanding Color Management by Sharma Color Management for Photographers by Rodney Universal Photographic Digital Imaging Guidelines (see link below) Links JKM 7/23/2013 Enhanced Images 26