There's not much out there on the Mac side in terms of good photo stitching software.
RealViz Stitcher (
http://www.realviz.com)
Works great...a lot of options...but costs an arm and a leg. Not worth the cost IMO. They did have a version called Stitcher EZ that worked well. Seems they've dropped it as of a few months ago.
PTMac (
http://www.versiontracker.com/dyn/moreinfo/macosx/15939)
Can be very advanced, but it's a bit of a bear to use and not very streamlined. Based on the Panorama Tools (PanoTools) package, a cross-platform Win/Mac/Lin set of tools.
LMStitch (
http://www.versiontracker.com/dyn/moreinfo/macosx/17359)
Haven't had a chance to test this one yet. Doesn't seem to have a lot of options or advanced use.
ArcSoft Panorama Maker (
http://www.arcsoft.com/en/products/panoramamaker/)
Currently using this a quarter of the time. Not the best solution I've seen totally but it's getting the job done for right now and is probably the best on the Mac side.
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Canon ships a program called PhotoStitch with some of their cameras and printers. Through the grapevine I've heard it's a darn good one, just haven't found a copy to test myself.
On the windows side there is a program called The Panorama Factory (
http://www.panoramafactory.com/) which is by far the best stitching software I've use to date. It'll allow a lot of interaction from a user, or minimal (wizzard-like use). The final stitched images are top notch. I'm currently running this program three-quarters of the time under VPC/Win2kPro...it's that good. It's excellent at handling exposure differences in photos, which are a major problem with visual tours in Real Estate (tight, indoor spaces).
The developer has said he's not going to release a Mac or Linux version:
"I'm sorry, but I don't have any plans for a Macintosh version. My time and resources are limited.
It may surprise you to learn that the income from this shareware product is not enough to support even one full-time person (i.e. myself). Most of my income (and professional time) comes from software contracting work. Unfortunately, this means that I cannot undertake a major new development effort like a port to Macintosh, so I've had to concentrate on the PC version. "
Photoshop CS has the ability built-in, but it's a craps shoot at best. Some times it works great, at other times it's pitiful. For source images of large, open spaces (landscapes and such, outdoors) it's a good solution.