Editing Spot color

{{Short description|Type of ink or pigment used in printing}}
[[File:RIAN archive 978876 Printing banknotes at Goznak factory in Perm.jpg|thumb|Printing [[Russian ruble#Banknotes|Russian 5,000 ₽ banknotes]] with a metallic spot color]]
In [[offset printing]], a '''spot color''' or '''solid color''' is any color generated by an [[ink]] (pure or mixed) that is printed using a ''single run'', whereas a [[process color]] is produced by printing a series of dots of different colors.<ref>{{cite web|url=http://www.pantone.com/help/?t=Process-color-vs.-Spot,-or-solid-color|title=What is the difference between spot and process colors?|archiveurl=https://web.archive.org/web/20170820162600/http://www.pantone.com/help/?t=Process-color-vs.-Spot,-or-solid-color|archivedate=2017-08-20}}</ref> 

The widespread offset-printing process is composed of the four spot colors [[cyan]], [[magenta]], [[yellow]], and [[Keyline|key]] ([[black]]) commonly referred to as [[CMYK]]. More advanced processes involve the use of six spot colors ([[Hexachrome|hexachromatic process]]), which add [[Orange (colour)|orange]] and [[green]] to the process (termed [[Hexachrome|CMYKOG]]). The two additional spot colors are added to compensate for the ineffective reproduction of faint [[Tint, shade and tone|tints]] using CMYK colors only. However, offset technicians around the world use the term ''spot color'' to mean any color generated by a non-standard offset ink; such as [[Metallic color|metallic]], [[fluorescent]], or custom hand-mixed inks. 

When making a multi-color print with a spot color process, every spot color needs its own [[lithographic]] film. All the areas of the same spot color are printed using the same film, hence, using the same [[Lithography#Modern_lithographic_process|lithographic plate]].  The [[dot gain]], hence the [[screen angle]] and [[line frequency]], of a spot color vary according to its intended purpose. Spot [[lamination]] and [[UV coating]]s are sometimes referred to as 'spot colors', as they share the characteristics of requiring a separate lithographic film and print run.

== Computer methods ==
There are various methods to incorporate rather sophisticated patterns of spot colors in the final [[prepress]] artwork. Software applications such as [[Adobe InDesign]], [[Adobe Illustrator]], [[CorelDRAW]], [[QuarkXPress]] and [[Scribus]] may generate spot colors as additional channels. [[Adobe Photoshop]] can also be used to generate soft edges (widely known as feathered edges) of spot colors. The dissolve effect provided by Adobe Photoshop layer patterns can be generated for any spot color.

== Optimizing usage ==
Generally the cost and potential for problems for a print job increase as one adds more spot colors, due to the increased cost and complexity of added process inks and films, and requiring more runs per finished print. However, because of the complicated process, spot colors are effective at preventing forgeries of [[money]], [[passport]]s, bonds and other important documents. Money printing for example, uses secret formulae of spot colors, some of which can be seen by the naked eye and some that can only be seen by using special lights or applying certain chemicals.

== Classification ==
Spot color classification has led to thousands of discrete colors being given unique names or numbers. There are several industry standards in the classification of spot color systems, such as:
* [[Pantone]], the dominant spot color printing system in the [[United States]] and [[Europe]].
* [[Toyo Ink|Toyo]], a common spot color system in [[Japan]].
* [[DIC Corporation|DIC]] Color System Guide, another spot color system common in Japan – it is based on [[Munsell color system|Munsell color theory]].<ref>[http://www.theinformedillustrator.com/2012/09/process-versus-spot-color.html The Informed Illustrator: Digital Spot Color Systems]</ref>
* [[ANPA color palette|ANPA]], a palette of 300 colors specified by the [[Newspaper Association of America|American Newspaper Publishers Association]] for spot color usage in [[newspaper]]s.
* [[GCMI]], a standard for color used in package printing developed by the Glass Packaging Institute (formerly known as the Glass Container Manufacturers Institute, hence the abbreviation).
* [[HKS (colour system)|HKS]] is a color system which contains 120 spot colors and 3,250 tones for coated and uncoated paper. HKS is an abbreviation of three German color manufacturers: Hostmann-Steinberg Druckfarben, Kast + Ehinger Druckfarben and H. Schmincke & Co.
* [[RAL colour standard|RAL]] is a color matching system used in Europe. The so-called RAL CLASSIC system is mainly used for varnish and powder coating.
Because each color system creates their own colors from scratch, spot colors from one system may be impossible to find within the library of another.

==References==
{{reflist}}
==External links==
* [https://www.castleprint.co.uk/spot-and-process-colours-explained/ Spot and Process Colors Explained]
* [https://spotcolormatch.com Creating color swatches or samples to match spot colors]
{{color topics}}
[[Category:Color space]]
[[Category:Printing terminology]]