Over the past few months, I've been able to test out the Blackmagic Design URSA mini 4.6K and see how it works on a variety of shoots. The camera is quite amazing, able to shoot RAW or ProRes, boasting of 15 stops of dynamic range. It comes close to the FS7 (which is 1 stop less, but $3k more), but I feel the image quality is better with the URSA. The native ISO is 800 and I would try to leave it there as the other ISOs give less dynamic range. The 1600 image tends to fall apart rather quickly (especially with higher compression rates). In a low light situation it's better to shoot 800 and bring it up in post. One thing some shooters have been finding is the classic Blackmagic fixed noise pattern. I've only run into it a few times when I was pushing the image dramatically in Premiere. The pattern shows up if the image is very underexposed and then brought up in post, especially if there's a lot of shadows in the shot. Shooting at 800 and getting proper exposure take care of these issues. This camera likes light.
There is a slight magenta shift or magenta vignette to the sensor, but it seems to differ per camera. My sensor looks pretty good. There is a tiny shift, not as dramatic as I've seen from other sensors. It seems to come into play when the saturation is boosted a lot in post (like 300%). So it's not as big of a deal as it's made out to be.
Ergonomically the camera is great, pretty light and has four 1/4"-20's on the top and bottom. With the side handle it's easy to do handheld from the hip or a low angle. An odd quirk is that the LCD screen needs to be flipped open to access the only power button. This may cause problems if an EFV is being used, the camera is rigged or on a gimbal.
Most cameras in this price range have built in ND, but the URSA doesn't. It's only an inconvenience. Look at the Alexa and Weapon and- no build in ND either. Blackmagic Design was going for a higher end professional camera and delivered quite well. The URSA mini works great on commercials and narrative projects when there's time light, put on ND, and control the image, not getting content quickly in the moment. This camera is built for a controlled environment, not so much for a run and gun workflow. As a cinematographer, I'm focusing less on the run and gun content, so this camera is perfect.
At NAB 2016 Blackmagic announced they will be releasing a dramatically new firmware update this summer. It will look similar to the RED menu system, utilizing the touchscreen and giving many more options (including anamorphic desqueeze). The current menu system is super basic and very similar to other Blackmagic camera menus.
And now for some footage:
In this spot I was able to test out the URSA. My laptop struggles cutting 4K so I shot 1080 with ProRes444 compression. Most of this was 120fps so it was windowed on the sensor. Below is a lighting diagram. It's a very simple setup. For lensing I used the FlareFactory 58mm lens (from Richard Gale Optics) along with diopters for the close up shots. The final shot is the FF58 with SLR Magic's 1.33x Anamorphot. I wanted to get a stronger flare, but couldn't get the leko far enough away due to being in a tight space. I'm very pleased with the image from this camera! I found it's better to expose hotter and bring it down in post. The shoulder has a nice roll off as you can see in the flare. It's close to the Alexa look, well worth it for the price.