FYI: URSA Mini 4.6k PL Back Focus Adjustment

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FYI: URSA Mini 4.6k PL Back Focus Adjustment

PostWed Apr 19, 2017 7:33 pm

This is just an FYI.

I needed to adjust the back focus for the our URSA Mini 4.6k PL and a Zeiss CP.2 50mm combo. We shoot mostly product related videos. The majority of the work we do goes to VFX where the product is rotoscoped out and place it in various sales related videos. The captures have to be sharp and clean. I need deep DOF to hold sharpness and give the VFX artists as much detail as possible.

Before using the camera and lens for the first time, I did a back focus check and wasn't surprised that it was a bit off. I needed to add .075mm to the standard .50mm that comes installed with the camera.

For those of you who may need to do the same here are the tools I purchased to do the job.

- Blackmagic Design's URSA PL Shim Set

- Wera Kraftform 7460 Hexagon Torque Screwdriver, (Part number - 05074840001) -

- 1/4 Inch Shank 2mm Hex Head Magnetic Screwdriver Bits -

- Siemans Focus Chart
Robert Olding

Mac Pro (Late 2013)
macOS Sierra 10.12.6
3.7 GHz Quad-Core Intel Xeon E5
32 GB 1866 MHz DDR3 ECC
AMD FirePro D500 3072 MB (x2)
URSA Mini 4.6 PL
DaVinci Resolve Studio 14
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FYI: URSA Mini 4.6k PL Back Focus Adjustment

PostWed Apr 19, 2017 11:07 pm

This is the wrench I use. It has the tension marked on a scale so very precise. ... id=1844010 ... 80_280.jpg

The colour of my handle is orange and the product code ends in a 1 versus the yellow handle ending in 2. I think the only difference is the colour.

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Rick Lang

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