Hi,
I found out about free lensing yesterday. Checked some references on the web.
This is what I found. Free lensing is the technique where you take pictures with the lens off the camera !
So, you get your camera, screw your lens of, and hold it before the cam to take pictures. Crazy huh!
What are the consequences:
No communication between camera and lens, so no aperture settings, which means you’ll work with full aperture opening of your lens. (unless you use an older lens with aperture ring)
No AF (you could have guessed that yourself, couldn’t you?)
No IS (image stabilization) of any kind. You’d be happy if you manage to keep lens and body more or less stable.
risk of dropping your lens while manipulating your camera.
…

so what on earth would make you want to do this?
by taking of the lens, you can play with the image DOF plane, like with a technical camera, a tilt-shift lens, or whatever system that allows to move the lens independently from the film plane (sensor plane)
this means your sharpness plane no longer runs parallel to your film plane.

a bit difficult to understand maybe, but look at the images.
You’ll see that I get sharp and unsharp in the same depth plane. Text on monitor is supposed to be flat, although only some lines are sharp, the others are not.
The lamp cover has some pearls sharp in front, some in the back, none in-between.

I’m not sure this is the best technique for tack-sharp images, but it can produce very artsy images at least. I took these some moments after I read this post, so I’m an absolute beginner. I will possibly never do something serious with this, but I thought it was funny enough to share.

If you want to give this a try, please note:
I won’t take responsibility for damage to your camera or lens.
Keep i mind that the sensor is at some moments disposed to the outside environment, never attempt this in a dusty area.
Lenses developed for a full frame camera will give better results, due to their bigger image circle.
try using some old analog lenses, they are cheap, and always developed for full frame negatives.