SI2K and Metabones BMPCC Speedbooster

[Bob Hart]

Joe.


Unless you are using the R1 in windowed S16 mode, you may be better off with a Speedbooster Ultra optic to the R1's full sensor from full size stills lenses. Because of the front element of the Speedbooster optical cell getting is the way, you cannot use most traditional cine film lenses. However the lenses approved for the Speedbooster Ultra optic will work fine.

I have used one in a custom mount on a Blackmagic "Big" URSA camera which has enough throat space to accommodate the optical cell. You would have to do a custom design for the IMS-Mount but it would not be hard. Unlike the later RED camera families with the sensor set so far back in the camera body, there is more workspace.

I don't know where the IR/anti-aliasing filter sits relative to the sensor on the R1 so that could be an inconvenience if it is too far forward both for the IMS-Mount Speedbooster mod I made for the SI2K and the Ultra Speedbooster mod I made for the "Big" URSA.

The rear element of the Ultra optical cell sits further forward of the sensor than the S16 version for the original BM Pocket camera. The Ultra optical cell extends the usefullness of the "big" URSA in that it can more closely match the BM URSA Mini 4.6K in the available field-of-view for a given lens focal length and also adds nearly one stop to the camera's ability in low light.

I was actually encouraged in the "Big" URSA experiment by similar developments here on the forum with the later generation of RED cameras.

LEEUWIN TESTS 30JUN - YouTube

[Bob Hart]

Further to the preceding reply here is some detail about the "Big" URSA fitment.

https://www.dvinfo.net/forum/blackma...rsa-4k-pl.html

https://forum.blackmagicdesign.com/v...ooster#p362389

If you want to go the Speedbooster Ultra 0.7x route, I will see if I can find my design drawings which would enable you to calculate the offsets for the IMS-Mount.