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Digressions

A few words about pictures in general

I appreciate a good image, and I will be posting some here. At the same time, I appreciate words, and I understand that there are times when words can communicate better — and more vividly — than any picture. I hope to demonstrate here that I can recognize both situations.

A lot has changed since I wrote the following three paragraphs:

I also am aware of the variety of browsers and systems in use. Some browsers support HTML frames; some don't. Some monitors work at 1280x1024, or even higher resolutions; others top out at 640 x 480. Some people, bless 'em, are still riding DOS bareback, and probably using text-only browsers like Lynx. Some folks turn images off because they are fed up with the waste of time for downloading them. Small-screen devices like Palm pilots and Web-equipped cellular phones are becoming common; their users want as few images as possible. And of course there are visually-impaired people on the Web. They might want larger type, or need to run the content through a text-to-speech device.

Image formats are another issue. There are strong incentives to switch from GIF to PNG; but browser support for the features of PNG images is generally incomplete. Flash is a complication. So is Adobe's rapid advance from Acrobat version 3 through 4, 5 and 6 to 7 (though the availability of free readers helps). Vector formats would be nice in some situations — if browsers could handle them. (JPEG — even progressive-scan — is well supported, thank the gods of the Internet.)

Then there's the issue of color palettes. These became important when most video cards were limited to 256 colors (8 bits of color depth). For complicated reasons, this led to the well-known palette of 216 "Web-safe" colors that minimized the unpleasant effects of browsers straining to match the colors in certain images. Now that "high-color" (16-bit) and "true-color" (24-bit) video cards are common, some say that Web-safe colors are no longer needed. But a technical analysis does not support this; and in any case "common" does not mean "universal" (The linked article puts the current population of 8-bit-color users as 6 percent.)

The technical analysis has moved (I've updated the link above) and, while the most recent survey says the percentages of Web denizens using 16-bit and 8-bit color are down to 1% and 0.5% respectively, those are far from zero in absolute numbers of users. They undoubtedly represent less developed countries for the most part, but may also be concentrated in some areas or cohorts of the U.S.

Color-display systems for personal computers can be divided into three categories:

The original 8-bit systems, able to display 256 colors maximum (with 20 or 30 reserved for O/S use.)
Intermediate systems having a 16-bit (or rarely 15-bit) color depth. These are called "high-color."
True-color systems, which predominate today, have a color depth of 24 bits and can reproduce 16,777,216 colors.

Web-safe colors were adopted as a cross-browser standard when 8-bit color depth was almost universal. The palette of 216 hues was chosen to minimize dithering, in which the browser tries to match a web-safe shade with one it does support. This can produce ugly cross-hatching. There is no guarantee that every browser out there supports the standard, and high-color systems have a completely different set of colors. I still use Web-safe colors commonly, though not in every case, and based on this I see no reason to stop.

It still adds up to what the Chinese might call "interesting times".

Web Page Design Standards

My goal is to design pages that work well at all resolutions, from the VGA standard (640 x 480, 256 colors) up through the high end (which I think means 32-bit color at 1280 x 1024). However, I work mostly at 1024x768 resolution, so you might find pages that don't look good on your screen. If you find such a case, I'll be happy to hear about it. Please drop me an E-mail and let me know.

I no longer use HTML frames at all, so there's no need for a <NOFRAMES> section anywhere on my site.

To accomodate text-only browsing and aural readout, I will always place an ALT tag in my image calls to tell those using text-only browsers what the image represents. And I will try to keep the size of my image files to the minimum compatible with clarity. (For JPEGs, the most common format on the Web, I've observed that anything below about 20k bytes often begins to look blurry or chunky.) Aural readers are likely to be poorly served for some time to come, since I'm just starting to learn about this mode.

My pages are now validated to HTML 4.01 Strict and CSS2 standards. There was one place where I launched a page in a new window, using the "Target" attribute of the Anchor tag; this required sticking with 4.01 transitional for that one page. There was no real benefit to it, so that's now gone. And you can call me a stick-in-the-mud if you like, but I'm sticking with static HTML.

The bottom line is: Although I've been at this game for over ten years, there might still be some rough spots in my pages. Bear with me. And remember that constructive criticism is always welcome.