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This article discusses the need for a colour specification in printing and the problems faced in colour printing. It proposes solutions such as colour space value specification and ICC colour matching system. The article also highlights the consequences of not addressing these issues and provides a proposal for future guidelines.
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Colour Printing Kazushige HATORI IOF IT commissionWOC2005 mapper and so on..
Summary • Background • Why is the colour specification needed ? • What are the problems in colour printing ? • How to solve them ? • Consequences and proposal
Background in colour printing - Nowadays • 2004 latest model canon personal inkjet printer, best one for 300euro, 35sec/sheet (normal quality 70% A4) • Over half of o-maps in competition use may be printed with course directly from OCAD8 in 2005 (even woc2005 public races)
Background in colour printing 2 - In near future • Double the speed with same quality in a few years (20sec/sheet, faster) • Pigment ink will be a standard in inkjet,any paper can be used
Summary 2 • Background • Why is the colour specification needed ? • What are the problems in colour printing ? • How to solve them ? • Consequences and proposal
General difficultiesWhy is the colour specification needed ? - Even if spot colour printing used according to ISOM • Different colours and qualities,between World Championships 2001, 2003, 2004 and 2005 - Recently • Spot colour printing is going to be dead now inprinting market demand - In near future • 4 colour process printing and personal printer printing by computer will be needed definitelyMUCH CHEAPER and USEFUL WAY!
ISOM2000 Why is the colour specification needed ? • Each C,M,Y,K ink is quite different from other printing ink, methods…
ISOM2010 draftWhy is the colour specification needed ? - Secret draft Not uncovered even for MC members yet • 3.5 PrintingAccurate colour printing should be realized for IOF events. Any printing method, eg: spot colour printing, may be used, if colours and resolution have the same quality as the colour specification.
ISOM2020 draftWhy the colour specification needed ? - VERY secret draft Not revealed (even for MC members yet) • 3.5 PrintingElectronic paper map must be used for IOF events. Other traditional methods, ex. map printing on paper, spotcolour ink printing, may be used, if colours and resolution have the same quality as the colour specification.
General difficulties 2Why is the colour specification needed ? - colour matching to spot colour ink • It is very very difficult to reproduce exactly the same colour as spot colour pantone ink in- 4colours process printing (ISOM2000)- personal printer printing (ISOM2010?) unless there is a more detailed colour specification
Summary 3 • Background • Why the colour specification needed ? • What are the problems in colour printing ? • How to solve them ? • Consequences and proposal
RGB value in OCAD ~ no senseWhat are the problems with colour printing ? - RGB value in OCAD
RGB value in OCAD ~ no senseWhat are the problems in colour printing ? - RGB value in OCAD • OCAD RGB value is uncalibrated / uncertain • That RGB value only makes sense in relation to printer driver colour settings • eg. more vivid graphic, more perceptual image, more monitor-like colours… • Each printer may reproduce rgb colour as it wants (according to its colour design).Sometimes big differences between even Canon and EPSON
Colour blendingWhat are the problems in colour printing ? -Realizing overprinting effects in 2ways • Blended colours – difficult wayonly realized in high-level softwaresame as real printing (subtractive colours) • Alpha channel blending – easier way transparency effecthowever different from real ink printing(additive colours) ~ OCAD goes with it now
Summary 4 • Background • Why is the colour specification needed ? • What are the problems in colour printing ? • How to solve them ? • Consequences and proposal
Colour space value specification How to solve them ? • Colour space value spec. (ex.sRGB, L*a*b*..) will help for exact colour reproduction • Use ICC colour matching system or • Next generation CMS on PC will be available soon - printing sample goes with ICC The colourSpecification CMSon PC + -> GOOD RESULTsame as spot colour
Alpha blending colour needed How to solve them ? • Alpha blending differs from real blending • Real Blending Alpha blending HOWEVER, Alpha blending methodmay be used for common web, PDF, and easyprint
Summary 5 • Background • Why is the colour specification needed ? • What are the problems in colour printing ? • How to solve them ? • Consequences and proposal
Consequences and proposal 1 - In order to realize colour printing by printer etc. in future • Color space value specification of colors on o-map will be needed for next ISOM For printing practically, You need to use ICC colour matching system for nowor wait next CMS for a while
Consequences and proposal 2 - In order to realize overprint effects • Alpha blending color specification may be needed in next ISOM More studies will be needed for both common use and high class print demand