I blogged about Stefan Hafenege before, he has developed a new version of his free tethering program. It’s specific to Mac and to particular Nikon DSLR models, but if that’s your combination then it looks like a great solution.
Read his description of the new version which is called Sofortbild on his blog, and download it from the Sofortbild Website.
Once again, well done to Stefan!
Stefan Hafeneger , has built a Nikon specific camera control app for macs which is now beta and freely available. He is using the Nikon SDK as well so should be able to implement much more Nikon specific controls than I am able to via WIA on Windows in my script.
Apparently he is able to understand the SDK as well – which means not only can he program better than I but his English/Japanese parsing skill is much higher than mine as well and I salute him!
I haven’t tried this myself but apparently it is easy to set up. See instructions here.
Update: But see comment below if you are a LR user as a plugin is avaiable to make it even easier.