background images in html

here is an example http://www.d5ive.com or another http://x2-movie.com/splash.html

my question is this: how do you load such a high quality image into the background in such a short time? i have high speed but is that it? does it preload the image? is it css to load it?

the image from the x-men site is only 46k... i guess that my other question is how to achieve such high resolution in such a small size? any links to good tutorials on how best to do this image optimization?

sorry if the questions are a little lame! ;-)

None of those images are really background images... They are put there with img tags...

But anyway, just use save for web in photoshop and play with the settings. Different qualities, blurring, etc. If you play with it long enough you can get any picture pretty small. there aren't really any other secrets than that though.

yup, what deker said. Plus the first one is made in flash, and it optimizes bitmap images in its' own ways.

excellent! it just seems that they are of such high quality... i think i need to do some testing in photoshop to get some proper optimization settings!

thanks for your help!

One thing that i have noticed helps, if lets say you have a black background like the first example, notice how "black" that image is? When you optimise with fewer overall colors it seems to make smaller files. The Xmen one was probably optimised using flash, which has real nice image optimising capabilities. If you are importing images into flash use good quality .png's otherwise they look over compressed.