I love the tight dof look that you can get with cine lenses. I have always been greatly saddened by the lack of dof in consumer and prosumer cameras. I have gone through a few iterations of building different half-assed diy dof adapters. This current one is based on a cd player motor spinning a ground down cd blank with one side sanded to a matte finish. The case is a 2 outlet electrical junction box painted black inside and out. It has a nikon lens mount from a $10 macro tube jb welded to the outside, an external battery pack, and a power switch.
The theory of a dof adapter.
Something having to do with the dimensions of the image sensor and the lens optics means that most digital videocameras have very wide depth of field. What depth of field means is that if you are interviewing them sitting at their desk chair, then their desk and the wall behind them are all in focus. The range of things that are in focus is called the depth of field. By using an adapter you can control this field with lens and aperture selection.
The way that the dof adapter works is by putting a secondary optics system directly in front of the camera. This lens projects its image onto a ground glass plane (or in my case, a scratched cd) in front of the camera, and then you focus the camera on it. You lose a bit of light in this process, but you also gain the ability to control your focus.
Professional versions of these can start a about a thousand dollars and go well up into the tens of thousands. Mine certainly is nowhere near those in terms of quality, but mine also probably cost about $40. The next step is going to be mounting it on a rail-type system, mounting the camera, and getting some macro filters for the videocamera.
Here are some pics of it.
If you want to check out an entry level 35mm adapter, then go to redrock micros site