Viewing Images on this Web Site
To view images from this web site, one's Windows Display video modes ought to be set for 24 bit color also known as 16 million colors with one's desktop sized to at least XVGA, aka extra super video graphics adaptor mode, or 1024x768 pixel screen size. Selecting either 256-bit color or 64k bit Hi Color modes will display color poorly on my or other photographer's sites. Using a monitor at VGA or SVGA screen sizes will require the nuisance of using scroll bars to view complete images. For additional information continue reading Monitor Basics.
The size and thus appearance of resolution of graphic images on computer monitors running Windows is dependent on three parameters: video mode, monitor screen size, and dot pitch. Windows video modes, which control graphic adaptor hardware, are set up using: Control Panel...Display...Settings
Video Mode Screen Size Setting:
Most current computers are set up at a screen size of at least VESA XVGA or 1024x768 at 16 million colors. If one selects a small video mode as the old 640x480 IBM VGA 4:3 aspect screen size, a given graphic image will be displayed on one's monitor relatively large. Conversely higher video modes as SXVGA, UVGA, and WUVGA would view a given image relatively smaller.
Video Mode Color Setting:
For viewing graphics on a Windows computer, one should select a video mode with 24 bit true color, aka 16 million colors or more precisely: 8 bits each of red/green/blue aka RGB. Each 8 bits contains 2³=256 values thus 256*256*256 = 16,777,216 colors. On the internet, 16 bit Hi Color, or worse indexed color at 256 colors, or 16 color modes, will display 24 bit true colors of both embedded images and web page graphics poorly. That is because resulting colors will be dependent on crude color palette table substitutions. In the past Windows computers often used lower color modes but today with color rich multimedia content increasingly in use, new systems are set up with true color.
Given the same monitor dot pitch, a large monitor screen, for example 21 inches diagonal, will display a given image larger when set to the same Windows video mode, for example 1024x768, as a smaller screen, for example 15 inches diagonal. In other words Windows fits the selected video mode to the screen space available on one's monitor. However users with large monitors are also likely to select a higher video mode than those with smaller monitors. That will result in a more similar image size display on either of two sizes of monitors with larger monitors just having more extra desktop space available outside the image.
Monitor Dot Pitch:
Current monitors commonly have a dot pitch of about 0.25 millimeters between RGB phosphors pixels, with different monitors varying as much as 20%. This equals (25.4mm/in)/(.25mm/pixel) = 101.6 pixels per monitor screen inch. Windows inhibits using video modes beyond which graphics adaptor or monitor hardware is able to support. Using a video mode in which there are more Windows desktop pixels across a monitor dimension than it has RGB phosphor pixels will not result in increased resolution or information.
Number of Phosphor Pixels on a Monitor:
Monitors are specified in the diagonal screen dimension. For standard 4:3 aspect monitors, the horizontal screen dimension equals 80% of the diagonal and the height 60%. However only roughly 90% of those lengths are viewable between monitor housings. That reduces numbers to about 72% and 54% respectively. So for a 17 inch diagonal monitor, the usable screen might be: 0.54*17*100 = 9.18 inches by 12.24 inches. Given a 100 pixel per inch phosphor dot pitch, the screen size would be 1224 by 918 pixels. For such a screen 1024x768 XVGA would fit well and 1240x1024 SXVGA would moderately increase information viewable. UVGA at 1600x1200 would add no new information even if the mode was allowed.
The color display of web images on different computer's monitors varies due to several factors which are not controllable. If one is running Color Management System aka CMS software with a calibrated monitor under a controlled ambient lighting, the display can be reasonably close. Most users do not run CMS nor are their monitor calibrated. Therefore images displayed by others are likely to vary considerably from computer to computer. The images displayed on these web pages are directly from master files and not the reduced gamut print files. That is standard practice on photographer web sites as images may be used for other commercial purposes beyond prints. Thus the only effective way to actually indicate true colors is to actually see an exhibited master print. There is also the issue of monitor gamma setting which effects brightness of displays. Generally gamma for MAC's is 1.8 and PC's 2.5. My displayed images were set up for a 2.2 gamma which is the consensus compromise Web graphic setting today and more importantly for me is what my printing lab uses.
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