Hi,
I have a placemark where I put an <img> in the <description> tag. This works fine, except that Google Earth tries to retrieve the image pretty much continuously.
Here are some entries from my Apache access_log:
83.160.134.139 - - [16/Dec/2006:15:07:39 -0800] "GET /webcam320.jpg HTTP/1.1" 200 10801 "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:49 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:50 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:50 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:50 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:50 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:50 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:51 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:51 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:51 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:51 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:51 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:52 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:52 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:52 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
83.160.134.139 - - [16/Dec/2006:15:07:52 -0800] "GET /webcam320.jpg HTTP/1.1" 304 - "-" "kh_lt/LT4.0.2693"
Interestingly, when you double click on the placemark, the description balloon opens, and the image is loaded (the first request), then while Google Earth is zooming to the correct place, there are no more requests, but as soon as it arrives and the movement stops, continuous requests start.
(At least it caches properly, so a 304 (not modified) is returned, but it's still pretty bad behaviour.)
This is using the very latest Google Earth (4.0.2693) on Windows. (Running as "Plus", but I doubt that makes a difference.) The same thing also happened with the 4.0.2416 version, although that one only sent about 1 request every 1-2 seconds.
The placemark in question:
http://mscha.net/geo/Fjordcam.kmz - Michael