Ursa Mini 4.6K review: worth the wait

URSA Mini 4.6k front view
Christina Fox
June 14th 2016 at 10:36AM : By

Blackmagic’s Ursa Mini 4.6K had been plagued by delays and an apology for its lack of a global shutter, but our camera specialist Christina Fox says the camera still delivers big

URSA Mini 4.6K shoulderBlackmagic Design's Ursa Mini 4.6K is a highly-anticipated, relatively inexpensive 4K+ camera offering up to 15 stops dynamic range that looks ideal for drama, commercials or even studio work.

The EF-mount model costs £3,800 (including VAT - compared to the existing £2,235 4K EF), which is relatively little for what is a high-spec camera. OK, you’ll need some accessories (see below), but if you’ve been shooting for a while you probably have some of them anyway.

When your new camera arrives it is tempting to rip open the box and pull out the treasures inside. But when you open the box you’ll be greeted by a gold envelope with a cheery “Welcome” written on it. This contains an SD card with Blackmagic’s camera setup installer and three manuals. It also includes a message from Grant Petty, the CEO, thanking you for buying the camera and asking for your suggestions and ideas for new features - a nice touch. Hope he follows up on that.

The camera records to CFast 2.0 cards, as its higher bit rates require faster write speeds. Blackmagic recommends cards by Transcend, Lexar and Wise. A 64GB card costs around £155, 128GB around £350 (inc VAT), plus you’ll need to buy a card reader. To start you need to format your card as HFS+ or exFAT. Blackmagic recommends HFS+ as it supports journaling, which can make it easier to recover lost data.

The Mini can record CinemaDNG Raw codecs with a choice of lossless 4.6K Raw or compressed 4.6K Raw. There are also ProRes 444XQ, 444, HQ, 422 LT and Proxy for Ultra HD or HD. UHD at 25fps in ProRes 444 XQ will give 21 minutes recording time on a 256GB card. A 10-second shot in UHD Prores444 is about 1.5GB. Thank goodness hard drives keep getting cheaper.

All the usual frame rates are on offer including 23.98, 24, 25, 29.97, 30, 50, 59.94 and 60 frames per second, depending on resolution. With the option of 40-120fps (in HD) for slow and fast motion. There is also a timelapse (interval recording) option. A 4.6K timelapse offers great opportunity to pan, crop or zoom any output in HD, or to a lesser extent in UHD.

Update and accessorise

One of the first things I did while waiting for the batteries to charge was to check for updates. Blackmagic announced firmware update 3.2 on the April 18 (go to https://www.blackmagicdesign.com/uk/support/family/professional-cameras to find out about the latest updates). Version 3.2 seemed to mainly concentrate on added features to make this a better studio camera, including tally support, talkback, colour correction, detail, colour bars and lens control (as Blackmagic launched a nice new 7-inch studio viewfinder at NAB, this is part of its push into the studio market). There was also improved colour reproduction on the LCD screen and a LUT (look up table) on the SDI output. All these things lie dormant until you plug it into a switcher that supports the SDI protocol (Blackmagic’s own ATEM units are probably the least expensive way into studio production, so the Mini can be part of a relatively low-cost set up).

As new firmware upgrades and sensor technology arrive, this might actually be a future-proof camera

The camera can also come with a PL mount (about £200 extra), and take B4 HD lenses using a £225 adapter to the PL model, while the EF version can make use of all those Canon lenses you acquired at the height of DSLR shooting. When the time comes you should also be able to swap out the sensor. This makes it an interesting prospect. As new firmware upgrades and sensor technology arrive this might actually be a future-proof camera.

The Ursa Mini is no lightweight at over 3kg due to the strong metal chassis. Then you spot the size of the HD LCD touchscreen. At five inches it is probably only bettered by the Ursa’s 10-inch screen. The problem with LCD screens is they are difficult to view in sunlight, which is a double nuisance here because many of the settings and adjustments are accomplished via the touchscreen.

The camera comes with an adjustable side handle with auto focus, auto iris and record buttons. It can also be removed and attached to an arm if you intend to use the camera with the good-value (£299) Blackmagic shoulder mount.

What you won’t find in the box are any batteries. So, you may want to factor that into your budget. The review model came with IDX V-mount batteries (a V-mount plate is £75). Gold mount batteries can be attached too. If you intend to use the camera outdoors and make use of the big sensor for shallow depth of field (DoF) you’ll need some ND filters and a matte box (as it has no built-in ND filters). You may also want to Google “IR pollution”, and then buy some UV/IR cut filters to reduce colour shifts in your image from infrared light.

URSA Mini 4.6K side view

Focus and exposure

There is peaking (green only – hopefully red will come in an upgrade) to help give you confidence in focusing. Plus with some EF lenses pressing the “focus” button on the camera body or side handle activates autofocus. That said the autofocus was slow and you may just find it quicker to do it manually. There is a Zoom button that gives a 1:1 pixel view, magnifying the image on the LCD screen and viewfinder – this can be helpful when focusing especially when using a prime lens. But it will only work in 4.6K and Ultra HD mode.

Press the “iris” button and the camera will expose automatically, if you have compatible lenses. With my 18-135mm Canon lens, changing exposure using auto iris was not practical when recording in low light. Pressing the button sent the camera to f32 and then to the suggested aperture. So, there was a temporary dip to black before the shot reappeared. However, this didn’t happen in daylight shooting. Hopefully this was just a glitch that will be fixed in firmware.

To change exposure while recording you use the forward and reverse media skip buttons to open or close the iris. These buttons need to have a different feel about them so that you know which is which without having to take your eye off the shot or press the adjacent REC button by accident. I’m sure this will not be a problem for anyone using this as a cinema camera where you can stop for a second take, and it probably isn’t an issue as a studio camera either, as these controls will be done by a vision control operator.

But, if you are going to use this as a single camera for documentary, make sure the lens has a manual iris ring. One way to make changing exposure more ergonomic would be to have a wheel on the handgrip like the C300, to change iris or ISO, or copy Sony’s FS5, which allows you to access all the essential functions of the camera via a joystick and assignable buttons on the handgrip.

For white balance, Blackmagic expects you to know your Kelvins. There is no need to frantically look for a white piece of paper because there is no manual white balance (or auto). To white balance you choose from 2500K to 8000K using the touch screen – while keeping an eye on what effect it is having in the viewfinder (or you buy a meter). Where everything is going to be colour graded anyway (the camera comes with DaVinci Resolve), it makes sense to just stick with one white balance setting for each location and do any adjustments in post.


If you don’t have time/money for a grade, the pictures are really good straight out of the camera, but the HDR pictures actually looked great after one-button correction in Final Cut

On the menu

When you press the Menu button there are six touch screen icons to choose from. The bottom three icons of histogram, audio meters and LCD overlays allow you to switch those items on or off the screen.

The metadata icon gives you the option to input info such as reel, scene, shot, take and angle, along with keywords and comments about the shot. The Format Card icon gives the option to format and so delete the cards. The Settings Icon takes you to the next layer of menus with options to change camera settings (such as ISO, White Balance and Shutter Angle). Next is the audio inputs and levels, then the Recording menu for choosing codec, frame rate and dynamic range, and finally the Display screen settings.

The shutter menu is expressed in angles only, so film DoPs should feel at home. But it would have been nice to have the option to have it expressed in fractions for those of us who think in shutter speed. The camera had been delayed because of problems with the 4608x2592 sensor, which now doesn’t have the promised global shutter, although any rolling shutter defects were pretty minimal.

This camera is not for really low light use. ISO goes from 200 to 1600 – 400 being the native ISO. So, you’ll need fast lenses if you don't have lights. However, there seemed to be minimal noise in the shadows, and the camera’s 15-stop dynamic range doesn’t just preserve the highlights, it also gives deeper blacks.

URSA Mini 4.6K rear oblique view

The camera had been delayed because of problems with the 4608x2592 sensor, which now doesn’t have the promised global shutter, although any rolling shutter defects were pretty minimal

High dynamic range

The Mini has two dynamic range options: film or video. The video setting uses the REC709 colour standard for HD video, still useful to those with no time for a grade. The film setting shoots video using a log curve giving you a higher dynamic range. While the Mini 4K offered 12 stops, the 4.6K can deliver 15.

You can set the dynamic range of the Mini’s touchscreen, SDI output and viewfinder independently. That way you can decide to monitor the video as recorded or in REC709. This can ensure anyone watching on a monitor sees something closer to the final look than the grey flatness of logs and gammas. There is no HDMI output (so you’ll need an SDI monitor - or Blackmagic can also sell you its £65 Micro Converter).

The 1080 HD OLED viewfinder is an optional extra (£1,229) and definitely worth it. Crisp and with good colour rendition it was essential when working in sunlight. If the Mini is your studio camera you might be happy with the LCD screen, but the new studio viewfinder (£1,275) is reasonable value too.

The verdict

There is no denying that this is a great value for money camera. While the magnesium body makes it robust and feel substantial, it means it also really needs to go on a tripod. Compared to other cameras in its price range it is heavy for on the shoulder shooting, especially once it is fully rigged with batteries and matte box. If you don’t have time/money for a grade, the pictures are really good straight out of the camera, but the HDR pictures actually looked great after one-button correction in Final Cut - and Resolve can do so much more. So, there’s no excuse not to shoot in film mode and make the most of those 15 stops.

If you are shooting drama, or commercials, where you can plan shots and have grip equipment, the Mini will deliver excellent pictures, and the additional pixels in its 4.6K sensor will be great in post if you need to reframe or stabilise the shots. With the addition of the larger viewfinder, this should really appeal to anyone needing to do studio or outside broadcast work. However, this is not a run-and-gun camera, where something like Panasonic’s AG-DVX200 and Sony’s PXW-FS5 or FS7 would seem to be more suitable.