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BMPCC 4K sensor plane marking


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There doesn't seem to be a sensor plane marking on the BMPCC 4K from which to measure when pulling focus. Has anyone else encountered this issue and/or come up with a solution for focus pulling in the absence of a sensor plane marking? 

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Its pretty easy to make an educated guess. Or drawing it on yourself by estimating the position. The chances are you'd only be a couple of millimetres out which isn't going to be an issue day to day. The combination of measuring and lens markings would typically have the same error as a sensible guess at sensor position.

Also the screen on the pocket 4K is sharp enough to check focus on.

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Thank you Phil. Yes, the BMPCC 4K's screen is sharp and I also like the focus assist feature, which is very helpful. I have a SmallHD monitor attached to the top of my camera and use that for monitoring because I have a large battery attached to the 15mm rods behind the built in monitor, which makes it hard to see. This setup generally works fine, however sometimes it is hard to judge precise focus on my SmallHD  when outside on a bright sunny day, so measurements are a big help in this case. 

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Sure but outdoors on a sunny day unless your going for razor thin DOF - the measurement could be a couple of mm's out.

If you measure how deep the sensor is in the camera body from the front of the lens mount with a tooth pick (you should be able to get within a mm or two, obvs don't touch the sensor). Then just all take your future measurements from the front of the lens mount and add those extra few mm's to the overall measurement. Then its bang on perfect - assuming your lens scale is accurate enough 

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