Continuous tone image

{{Short description|Image in which each point can transition smoothly between shades}}

File:Red_Fuji_southern_wind_clear_morning.jpg, the second print in Hokusai's Thirty-six Views of Mount Fuji (20th century reprint). Wood block prints like this are an example of a continuous-tone image.]]

A continuous-tone image is one in which each color at any point in the image can transition smoothly between shades, rather than being represented by discrete elements such as halftones or pixels.{{Cite magazine |title=Understanding Continuous Tone and Halftone Printing |magazine=Printmaking Today |last=McCulloch |first=Joseph |pages=34–40 |volume=20 |issue=4 |author-link=Joseph McCulloch (artist) |year=2008}}

File:Halftone example CMYK.png). Although halftone images are not continuously toned, they can appear continuous with high enough resolution or when viewed from a far enough distance.]]

Examples of continuous-tone images are natural phenomena,{{cite book |last1=Elkins |first1=James |author1-link=James Elkins (art historian) |title=Why Art Cannot Be Taught: A Handbook for Art Students |date=2001 |publisher=University of Illinois Press}} images produced with dye-based processes,{{cite journal |last1=Sweeney |first1=Megan |title=Dye Sublimation: An Overview |journal=Journal of Imaging Science and Technology |date=2012 |volume=56 |issue=2 |pages=220–226}} images produced with certain analog printmaking processes (intaglio, block printing, stone lithography),{{cite book |last1=Anderson |first1=Katherine |title=The Printmaking Primer: A Beginner's Guide to Printmaking Techniques |date=2015 |publisher=RIT Press}} and paintings. Halftone prints (as produced with inkjet and offset printers), traditional film, and digital screens are not truly continuous-tone since they rely on discrete elements (halftones, grains, or pixels) to create an image.{{cite book |last1=McCullough |first1=Michael |title=Digital Media: A Practical Guide for Artists and Designers |date=2018 |publisher=Wiley}} However, the term applies when the appearance is so smooth that the breaks or gaps between tonal values are imperceptible.{{cite book |last1=Stork |first1=David |author1-link=David G. Stork |title=The Science of Image Processing: An Overview |date=2013 |publisher=Springer}}

TV, computer and phone displays are effectively continuous. Purely analog video signals can provide infinite tone variations according to their gamut.