Okay, this is based on my experience with Bildindex -- I don't speak German (I can read it a
little, and my father-in-law has a PhD in German, which helps on words that really get me stuck). I have not had any real luck with the search engine.
The key to using Bildindex is to kinda sorta already know where you want to be looking -- which museums you want to noodle around in. Figure out what city (and country) they're in. And figure out the German names for the city and country, too.
First, I click on
Orte on that top menu.
Usually, if I'm using Bildindex to start out with, it's because I'm looking for something in a German museum; but if I'm looking in other countries' museums, I can select 'em on the pull-down menu at top left.
Now, you click on the alphabet to get to the city where the museum's located. The left-side menu is pretty much arranged like File Manager in a Windows system. I'm going to click any time I see the word
Sammlungen ('Collections') and
Kunstgewerbe ('Arts and Crafts'), because that's generally the kind of thing I'm looking for.
Then you usually have to go poking around to get to the exact category that interests you. The items within each category are generally organized chronologically.
When I find an image I'm interested in, I can click it for an intermediate blow-up (480x600), but I prefer looking at the large-sized version (1120x1400). The way you can get directly from the thumbnail to the biggie size -- do a right-click and find the URL for the image. Copy and paste the URL into a new window. The last letter before the ".jpg" will be a "c" -- replace it with an "a" to get the big size.
Bildindex is great for German collections, not so hot for other stuff. Some of the other systems I like using:
The British Museum Compass;
V&A Access to Images;
Insecula (especially for the Louvre's collections);
Fundación Lázaro Galdiano; and
KIKIRPA (for Belgian museum collections). For manuscripts, I used to like
KB/Meermanno's Medieval Illuminated Manuscripts (sometimes it doesn't work too well) but
Gallica and
Mandragore at the BNF are pretty cool.