Background

My anamorphic setup with BMPCC 4k grows as a huge monster.
So I need some tiny setup for location scouting.
And I decided to use the BMMCC.
For tiny setup, I need to find a single zoom lens which covers all focal length range of BMPCC 4K Anamorphic 2.8K mode.

BMPCC 4K Anamorphic 2.8K mode focal length range

Taking lenses

My lens set of Leica R is the following.

• 35mm Elimarit F2.8
• 50mm Summicron F2
• 90mm Elmarit F2.8
• 135mm Elmarit F2.8

BMPCC 4K Anamorphic 2.8K mode crop factor

With Full 4K mode,  the sensor width is 18.96mm for 4096 pixels.
With Anamorphic 2.8K mode, the vertical resolution is 2880 pixels.
So the sensor width is: ( 18.96 / 4096 ) x 2880 = 13.33125 mm.

So the BMPCC 4K Anamorphic 2.8K mode crop factor is: 36mm / 13.33125mm = 2.700.

And I use Metabone speedbooster 0.71x.

The final crop factor is: 2.7 x 0.71 = 1.917.

The full-frame equivalent focal length range

Multiply 0.5 for 2x Anamorphic lens.

• 35mm Elimarit F2.8
  • 1.917 x 35 = 67.095mm (Taking lens only)
  • 1.917 x 35 x 0.5 = 33.55mm (with 2x Anamorphic)
• 50mm Summicron F2
  • 1.917 x 50 = 95.85mm (Taking lens only)
  • 1.917 x 50 x 0.5 = 47.925mm (with 2x Anamorphic)
• 90mm Elmarit F2.8
  • 1.917 x 90 =  172.53mm (Taking lens only)
  • 1.917 x 90 x 0.5 = 86.265mm (with 2x Anamorphic)
• 135mm Elmarit F2.8
  • 1.917 x 135 = 258.795mm (Taking lens only)
  • 1.917 x 135 x 0.5 = 129.397mm (with 2x Anamorphic)

BMMCC focal length range

BMMCC crop factor

BMMCC sensor width is 12.48mm.

The crop factor is: 36mm / 12.48mm = 2.8846.

And I use Metabones speedbooster 0.58x.

The final crop factor is: 2.8846 x 0.58 = 1.67.

The full-frame equivalent focal length range

• For 35mm Elimarit F2.8
  • 67.095mm / 1.67 =  40.18mm (Taking lens only)
  • 33.55mm / 1.67 = 20.09mm (with 2x Anamorphic)
• For 50mm Summicron F2
  • 95.85mm / 1.67 =  57.40mm (Taking lens only)
  • 47.925mm / 1.67 = 28.69mm (with 2x Anamorphic)
• For 90mm Elmarit F2.8
  • 172.53mm / 1.67 = 103.31mm (Taking lens only)
  • 86.265mm / 1.67 = 51.66mm (with 2x Anamorphic)
• For 135mm Elmarit F2.8
  • 258.795mm / 1.67 = 154.97mm (Taking lens only)
  • 129.397mm / 1.67 = 77.48mm (with 2x Anamorphic)

These are the focal length range to be covered by one single zoom lens.

EF mount zoom lens covers all focal length range

For location scouting, I don’t want to attach the anamorphic adapter.
So required range is from 20.09mm to 77.48mm.
After some research, I found the following lens.

Canon EF-S 15 – 85mm / F3.5 – 5.6 IS USM

This lens covers all the range perfectly.

But one minor problem is there

EF-S (not EF) lenses are designed for the APS-C sensor.
So all EF-S lenses have the plastic cap on the rear element.
This plastic cap is hitting the Metabones.

But there’s a solution!

Just remove the plastic cap by a plier.

Final setup image

Light enough for location scouting.

Next

Match the exact focal length between BMPCC and BMMCC and mark it on the zoom lens.