Monitor Sizes Monitor sizes in the US are

Monitor Sizes • Monitor sizes in the US are measured in inches, diagonal distance. 20” (inches)

Aspect Ratio • 4: 3 is most common 16: 12 • 16: 10 is common for wide screens 16 20” (inches) 12 16 10 18. 87” (inches)

Aspect Ratio • 5: 4 is common for LCD’s (non-widescreen) 15 19” (inches) 12 16 10 18. 87” (inches)

PPI / DPI • Displays: Pixels Per Inch – 60, 72, 96 are common • Printers: Dots Per Inch – 300, 600, 1200 are common • 96 X 15 = 1440 px wide • 96 X 12 = 1152 px high 1440 px wide 15” 19” (inches) 12”

Over-Sampling 7 Megapixel photo • 2880× 2304 5: 4 6, 635, 520 pixels. • 32 -bit color 2^32 = 4 billion different colors – 4 bytes per pixel • Grand total 24+ Megabyte file without compression. • What happens when you display this image full-screen on this monitor? 1440 px wide 15” 19” (inches) 12”

Over-Sampling • Original Picture • What you really see on a 19” monitor.

Printing • 600 DPI printing • How much resolution? 11” X 8. 5” • 600 X 11 = 66, 000 dot or pixels across

Under-sampling • Original Picture • What you see on printed photograph Original picture could have been sampled at a higher rate and the printed version would look better.

Printing Issues? • Is over sampling ever an issue when your output is a printed photo? • Even though most digital photos (10 Megabits or smaller) are under-sampled, why doesn’t it matter?

Crux of over-sampling? Device perspective: • What the device can produce in terms of resolution. Human perspective: • What the human can perceive with the naked eye. • 600 DPI is necessary for printing fonts, • 600 DPI is overkill for printing photographs. • Why?

Resolution Depends on Content • Fonts are in fact vector-based, limitless resolution. • Fonts have smooth curves • Human eye can see jaggies in fonts are 120 DPI. • Photographs have blended colors and gradients. • Unless there are miniscule details, Human eye can not see jaggies in photos that are 120 DPI.

Practical Advice • Modern digital photography (10 Megapixels) is way ahead of display resolution. • However, modern digital photography is still behind of print resolution. • Unless you are going to print, 5+Mp is enough. • Example: 8 X 10 vs 16 X 20.