HELP! Fujinon lens with Ursa Mini Pro 4.6k

I just got our Ursa Mini Pro 4.6k camera and I was hoping to put our existing Fujinon ENG lens on them through the B4 Mount but the B4 receiver seems to be twice the size (approx) of my Lens. Its the right connection, just my lens is too small. Everything I read said these would work but apparently I missed something. I'm guessing being an HD lens and not a 4k lens would have something to do with it. Does anyone know of an adapter or step up I can get to make this work?

Blackmagic Ursa Mini Pro 4.6k with B4 mount (also have EF mount)

Fujinon HTs18x4.2BERM-M6


Thanks for any help you can provide!

Basically I need this but the opposite direction...
https://mpex.com/jvc-2-3-lens-mount-con ... aptor.html

That is only a 1/3" tv lens. You can only use 2/3" B4 lenses.

Sent from my SM-G960F using Tapatalk

Is there any hope at all for my situation? Any secret custom adapter websites I should know about?

Sorry, no

Actually guys, you need ENG B4 Mount lenses designed for 2/3rds 3-CCD sensor cameras, or the DigiPrimes thst were for 2/3rds sensors. The ENG Zooms also need,to have the Hirose plug attached to them, to connect to the camera to communicate with and power the lens. I also have a 1/2 hot shoe ENG lens, thst is B4,but it will not work, no cable, and the B4 hotshoe Mount is different, somthis lens on,y fits a few Sony ENG DVCam Cameras.

Even if the 1/2 or 1/3rds lenses slukd mlunt, you would have severe vignetting as these lenses were designed for much smaller sensors. I would be like using a S16 lens on a MFT or S35 sensor camera. It just is not going to work.
Cheers

Actually guys, you need ENG B4 Mount lenses designed for 2/3rds 3-CCD sensor cameras, or the DigiPrimes thst were for 2/3rds sensors. The ENG Zooms also need,to have the Hirose plug attached to them, to connect to the camera to communicate with and power the lens. I also have a 1/2 hot shoe ENG lens, thst is B4,but it will not work, no cable, and the B4 hotshoe Mount is different, somthis lens on,y fits a few Sony ENG DVCam Cameras.

Even if the 1/2 or 1/3rds lenses slukd mlunt, you would have severe vignetting as these lenses were designed for much smaller sensors. I would be like using a S16 lens on a MFT or S35 sensor camera. It just is not going to work.
Cheers

What really sucks is that I have that hirose plug and it works with the blackmagic camera but the lens doesn't fit on the mount. Bad luck I guess.

You just boughed the wrong lens. Sell it and buy a 2/3" B4 back..

Daniel, what distance do you use to set backfocus on your B4 ENG zooms? I used to use 7-9 meters with my Sony ENG cameras, but see BM, and other sources are recommending 20-25 meters.
Cheers

Full zoom in.. So it depends on the lens.. But even with the 66x Box lens i do a full zoom in.. Then go back.. Hit the screen to get magnification.. And check if it is sharp enough..

I know how to do it, going from full zoom in to full zoom out. My question was, how far from the camera do you set your focus target chart, 29 meters or ?
Cheers.

Don't use the focus chart that often.. We store cameras and lenses seperate so have to perform backfocus every time we go on job..

i always pick something in the distance that has a very sharp edge with black and white or very high contrasting colors.. Then setup my back focus and repeat the steps 2 or 3 times if needed.. Running 4K and having a Inferno on top of the camera you can often clearly spot if it is sharp enough over the range..

Thanks, yes doing the badkfoucs or st least checking each time the lens is mounted is a good idea.
While we are in the subject of Fujinon B4 zooms, I have an extra Zoe remote zoom and start/stop controller available if anyone is interested.
Cheers