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hat. ou. ee. s. N ot. hat. ou. et. W. Y. S. I. W. Y. By Philip Lawson. G. Luminosity. Resolution. Colour. What You Get. Infinitely Bright. No Light. Light. In the real world, Luminosities range from:. Bright EV 17 1 EV = x 2. Dark EV 5. Light meter.

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  1. hat ou ee s Not hat ou et W Y S I W Y By Philip Lawson G

  2. Luminosity Resolution Colour What You Get

  3. Infinitely Bright No Light Light • In the real world, Luminosities range from:

  4. Bright EV 17 1 EV = x 2 Dark EV 5 Light meter • The light meter can only measure a middling range of Luminosities:

  5. Max Min High Key 1 Film Emulsion • The Film Emulsion can record only a narrower range of Luminosities7 - 9 EV

  6. 2 Film Emulsion • But it is our choice which range to expose on Max Min Low Key

  7. 3 Film Emulsion • If the film stock has a dynamic range of 7 EV it has a tonal range of 27 = 128 levels • If the film stock has a dynamic range of 8 EV it has a tonal range of 28 = 256 levels • If the film stock has a dynamic range of 9 EV it has a tonal range of 29 = 512 levels

  8. Film Scanners • The Film Scanner converts these into Numbers in the range 0 -255 255 128 0 • It might not be able to record the full range of Film Luminosities

  9. Print Scanners • The Print Scanner suffers in that it • Is scanning a print that already has a reduced luminosity range • Is scanning the print by reflection 255 128 0

  10. The Monitor 1 • The monitor, being a light source is capable of a large dynamic range 255 128 0

  11. The Monitor 2 • This is adjustable via: • Brightness • Contrast • Gamma

  12. The Print • The Print, being a reflective medium is only as bright as the base paper and the light source • And as dark as the minimum reflectance

  13. Luminous Range • Strive to retain the highest range of luminosities at EACH conversion.

  14. Ensure scanner settingsdeliver a histogram showing even distribution over the full range. Luminous Range • Transparent Film has a higher latent DMAX than Print, so use a FILM SCANNER, min DMAX = 3.6 • Use the best image sources • IF possible scan to 16-bit grayscale and retain for a.l.a.p.

  15. Caution • Care when modifying the image • BRIGHTNESS • CONTRAST • A pixel cannot be brighter than 255 • Burn out • A picture cannot possess a greater dynamic range than 256

  16. Infinitely Bright No Light Colour • In the real world, Colour is absolute and of infinite variation • Each Primary R, G & B, may be thought of as a Colour Luminosity and follows similar degredation

  17. Colour Gamut • The Gamut of visible colours is described by the LAB space in the Chromaticity diagram

  18. Bright EV 17 Dark EV 5 Colour Photometer • The Colour Photometer can measure both the absolute and relative (Colour Temperature) ranges

  19. Max Min Film Emulsion • Film Emulsions record colour differently (CYM) • Manufacturer/Stock • Reciprocity Failure

  20. Film Gamut • The Gamut of the Film Emulsion is described by the EKTA space in the Chromaticity diagram

  21. 255 128 0 255 128 0 255 128 0 Film Scanners • The Film Scanner converts Red, Green and Blue into Numbers in the range 0 - 255

  22. 255 128 0 255 128 0 255 128 0 The Monitor 1 • The monitor, being a light source is capable of a large dynamic range

  23. 255 128 0 255 128 0 255 128 0 The Monitor 2 • Provided that you’ve got it set right!

  24. The Monitor 3 • 256 Colours or “High Colour (16-bit)” will give you a Posterised representation • Must use “High Colour (24-bit)”

  25. Monitor (RGB) Gamut • The Gamut of the Monitor is described by the RGB space in the Chromaticity diagramNote the mismatch

  26. Your Phosphors and selected colour temperature The Monitor 4 • However the colour that you get is influenced by:

  27. Your Gammasettings The Monitor 5 • However the colour that you get is influenced by:

  28. The Monitor 6 • However the colour that you get is influenced by: • Your Profiles

  29. The Monitor 7 • The colour that you SEE is influenced by: • Any funny desktop coloursor artificial light

  30. The Programperforms the RGB -> CYMKTranslation The Print • The Print, being a reflective medium has Cyan, Yellow and Magenta translucent inks applied

  31. Print (CYMK) Gamut • The Gamut of the Printer is described by the CMYK space in the Chromaticity diagramAlthough this is very dependant upon the light under which it is viewed

  32. Colour Range • Whilst modifying colour balance, ensure that you do not create an OUT OF GAMUT colour

  33. The Printer 1 • The Printer make numerous Necessary and Unnecessary Corrections • Colour Space

  34. The Printer 2 • The Printer make numerous Necessary and Unnecessary Corrections • Transferand • Bleed

  35. The Printer 3 • The Printer make numerous Necessary and Unnecessary Corrections • Mode

  36. The Printer 4 • The Printer make numerous Necessary and Unnecessary Corrections • Quality • Media • Halftoning • Adjustment

  37. The Printer 5 • Basic Advice • Print at highest Quality (1440 dpi) • Select the Correct Media Type • Use “Error Diffusion” Halftoning • Use “Photo-realistic” Colour Adjustment • Not “Automatic”!!

  38. MonitorICC Profile ScannerICC Profile PrinterICC Profile Kodak CDICC Profile Characterisation • Colour Management requires each device to be Characterised (by an ICC Profile)

  39. Profiles • Each Device is Characterised by a PROFILE that in turns needs Calibration

  40. Your Gammasettings for the Monitor Calibration • Calibration requires • Consistent Conditions • A Known Calibration Source

  41. Profiles • Photoshop manages your Profiles

  42. Colour Range • Use a scanner that Optimises the dynamic range of each colour independently. • Colour Casts can easily be eliminated • Take care when modifying the image • BRIGHTNESS • CONTRAST • Ink is not permanent. Protect from extreme light sources and Save data files.

  43. Resolution • In the real world, the resolution that we achieve is governed by: • Focus • Resolving power of lens • Camera Shake • Heat Haze

  44. Film Emulsion • The Film Emulsion is limited by the clumping of the grains. • Typical Resolving power is <50 lpmm Max = 1750 lines 24mm 35mm

  45. Film Scanners • Typical Film Scanners can detect 2700 d.p.i. • This is sharper than the finest level of detail but not enough to see the individual grains. Max = 4000 pixels 24mm 35mm

  46. Print Scanners • Typical Print Scanners can detect 600 d.p.i. • On a 5” x 7” Printthis would produce4200 pixels and a38Mbyte file. Max = 4200 pixels 5” 7”

  47. The Monitor 1 • The monitor resolution can be a number of prescribed settings LESS than the number of Phosphor dots on the screen. • Choose the highestas this gives youmore desktopspace for all thosepalettes

  48. The Monitor 2 • Always Zoom In or Out and Pan around. • Learn to use the quick keys: • Ctl-0 • Z followed bydrag a rectangle • Ctl + drag a rectanglein the Navigator • Space Bar

  49. The Monitor 3 • NEVER change the Image Size down • This throws vital information away!

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