It depends on which DoF adapter you are using.
You SHOULD be able to use both the lens’ aperture ring as well as the camera’s exposure controls to find a balance that gives you the DoF you want as well as proper exposure. Unfortunately, you are using lenses that does not allow you iris control on the adapter (I’m guessing you are using SLR lenses designed for a different purpose).
No, manipulating the camera’s iris control no longer has any effect at all on DoF, that is now a function solely of the front lens. Since yours is always shooting wide open, you will always have the shallowest DoF that lens will allow.
I personally use a combination of things. I use the P+S Technik converter, which does not use the camera’s native zoom lens… you take that lens off and attach the converter directly to the camera body with just a little relay lens. That little relay has another iris in it, which I primarily use for exposure. The cine lens’ iris then I primarily use to control DoF (and frankly, I usually keep it pretty wide). In some instances, I will put neutral density filters in the matte box. A combination of these three things gives me proper exposure and the desired DoF.
You said you don’t want to buy any filters, but frankly you need to… they are an important tool (actually what you really need to get are different/proper lenses, but the filters are a cheaper temporary fix). What would be most helpful is a set of three ND filters (.3, .6, and .9). If you use gelatin or polyester filters they are actually very cheap. You can pick up a set of three 4×4 ND filters for less than a hundred bucks.
T2
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Todd Terry
Creative Director
Fantastic Plastic Entertainment, Inc.
fantasticplastic.com
