The 5D mkII is a real deal changer. The much-coveted depth of field of 35mm is now a hand held possibility. As with all tools within financial reach of mere mortals its awesomeness comes with a few caveats.Of these, the most prominent and much talked about is 'jello-cam’. Rolling Shutter is temporal artifact caused by the way CMOS sensors scan across an image frame. Things move during this time and create a visible distortion. In the case of the 5D this can be quite prominent. But a bit of judicious testing and thinking on a practical level reveals that this problem can be overcome. For the best part this means working at a lower shutter speed than would seem sensible. Anything under 1/80th second has appeared fine. I think a lot of the ghastly wobbly shots online come from the camera being used by people from a stills background, where adjusting temporal sampling, the shutter speed is a totality normal way of manipulating exposure. Accept in the case of the 5D's video mode the higher up the shutter speeds you go the more exaggerated the rolling shutter becomes. This leads to the use of neutral density filters to control the exposure. Obviously you can use the aperture but this leads to silly f-stops that destroy the depth of field and introduce diffraction-induced softness to the image. A more pertinent problem that has no solution is the terrible aliasing, especially on brick walls! This is where creative use of depth of field comes in handy.
In many ways getting decent images out of this camera demands treating it much like a real motion picture camera. Thinking about you shots, planning and testing where you can push it. I have been exploring workflow options. My key focus has been on effects work and grading the 5D's output. I have much to say in this area but i'll save that for a latter post.
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