I've done it during a few e-sessions. It's is difficult, but I enjoy it. I plan on doing some more of it. I usually forget it's even an option. I need to put a sticky note on my camera to remind me.
@TTLKurtis -- certainly gives you a different look than you would be able to get with vanilla T/S lenses, plus depending on how you let light get in you can get some interesting flare effects.
If you have old Nikkor lenses with the aperture ring it is quite easy to get a better more even effect because you can stop it down like a real TS lens. Free lensing at f2.8 is tough for sure. Literally nothing is in focus.
I have tried it during weddings last year but there's no way I can find them right now. This was a pic I snagged during Tony Hoffer's shootout at G3. It is pretty tricky to do but does have a pretty cool look. This was with the 105 f2 DC
I'm interested in finding out if freelensing/lensbaby composer pro is actually professional. I saw Brenizer use the technique for several photos but I'm thinking it's more of a hobby than for professional photography. I can replicate the effect in Photoshop for freelensing which is why I'm wondering why I should bother taking photos by using freelancing technique or even use a Lensbaby Composer Pro. I can use the technique using a nifty fifty which seems to be a good handheld freelens lens and can manually focus while I'm composing but it just seems kinda silly. Any opinions?
So basically it's a no-go for anything besides a very carefully controlled portrait session. And even then the purpose seems to be to get as little of the image in focus as possible.
I use it during weddings and engagements very regularly, it's not that difficult once you know how to do it. Including removing the lens, manual focusing etc it usually takes me around 30 seconds to nail a shot.
It's certainly not for everyone but I enjoy it. Best with f/2 lenses in my opinion. You can do it with any Canon mount lens, with Nikon they have to be manual aperture ring lenses.