Am I missing something really simple?
You are using TIFFs. Browsers generally only support web-centric image formats and by definition, that means GIF, PNG or JPEG. The rest is handled via plug-ins, for TIFF that is Quicktime in most cases and even then content can be suppresed based on the user's configuration. SVG may allow you to embed addition la data and file formats, but that should not be taken as a way of using non-standard formats oin web pages. Since there is no real interest in SVG, support for it in most browsers is the bare minimum. Some of them don't even antialaias text... You would do much better to publish your stuff to Flash files, at least that way everything shows up correctly.
Mylenium thanks for your insight.
Should it matter that I'm placing a TIF into the SVG if I'm embedding? I could see it being a problem if I wanted to save it as linked (so there would be two pieces for the file).
Right now my organization is using PNGs for our art (within a web page). I have had requests for making the images and callouts larger. I was considering SVG because it can be scaled up within the browser (by the user) and it has the added bonus of the any text inside the art being searchable.
I've never experimented with Flash graphics. Can it offer similar advantages? Particularly with the ability to scale the art up.
Otherwise I expect our need to have larger art will require a minimum of two sets of web images with an interactive method to see the larger file if desired by the user. Since I'm looking at an art library of over 6 thousand images (before translation or needing multiple sets/formats), this could become an automation nightmare very quickly.
If you need to scale content, you should look into Photoshop's Zoomify export, which creates a Flash file with embedded multi-res tiles of an image. Since the tiles are loaded as needed into view, you can handle very large images that way, i.e you only create the largest version and let the export and Flash file handle the rest. I'm sure you could also find other alternatives that work similarly. Another option might be to use InDesign and define interaction there by ways of special commands, then use XFL (Export to Flash), which can be imported and interpreted by Flash for generating a final SWF. You even can get some transitions. On the same topic, look into Captivate and last but not least Flash Catalyst, currently available as a public beta on Adobe labs. Building interactive Flash content is not that hard with those tools....