RAW Power!

In the video, we demonstrate one way to create depth and contrast for HDR in a hopelessly cramped living space (16 m2) using lighting modifiers – specifically the Nanlite Projection Mount and Aputure Lantern Softbox – along with the Nanlite Forza 300 and Forza 60.

We’ve spared no effort in order to get the most accurate colors possible: from choosing the correct color space, to white balancing with the X-Rite ColorChecker, switching over to DaVinci Resolve, and calibrating our LG OLED with Calman Home for LG – and now seemed like the right time to pick up some lighting, not only with accurate color, but just as importantly, lighting that can be shaped to create depth and contrast for HDR imagery. Because unless lighting is planned from the very inception of an HDR project, the end result will be little more than a somewhat brighter LDR image.

The cube shape makes the Forza LEDs excellent for stacking on shelves; their compact size and weight mean they’re easier to haul around and shoot in confined spaces (see above!); the clamp (included with the Forza 300 & Forza 500) that attaches to a C-stand, allowing the power supply to be slung over the side of the stand, is impossibly elegant; and the Forza lights earn extra points for being rugged and good-looking. Both the projection mount and the lantern softbox take just seconds to set up and disassemble. And did we mention the lights also pack a punch? 🔥

Concerning our workflow, we first record ProRes RAW HQ with the Ninja V, using false color to avoid clipping. Those that moan about the Sony’s lack of internal RAW should be aware that an external monitor is pretty much essential for HDR (it’s recommended that a display capable of on-set monitoring of no less than 800 nits be used for HDR acquisition) and that SSDs are considerably more economical than V90 or CFExpress cards. Our Samsung 850 Pro 1TB SSD ran $450 when we bought it three years ago, while a single Panasonic 128GB V90 card runs a staggering $399 as of this writing! Anyhow, once we’ve finished our shoot, we transcode the ProRes RAW to ProRes 4444 in Apple Compressor prior to importing the media into Resolve.

Steer clear of recording XAVC S-I 4:2:2 internal if at all possible. Art Adams explains:

The Y’CbCr encoding model is popular because it conceals subsampling artifacts vastly better than does RGB encoding. Sadly, while Y’CbCr works well in Rec 709, it doesn’t work very well for HDR. Because the Y’CbCr values are created from RGB values that have been gamma corrected, the luma and chroma values are not perfectly separate: subsampling causes minor shifts in both. This isn’t noticeable in Rec 709’s smaller color gamut, but it matters quite a lot in a large color gamut. Every process for scaling a wide color gamut image to fit into a smaller color gamut utilizes desaturation, and it’s not possible to desaturate Y’CbCr footage to that extent without seeing unwanted hue shifts.

My recommendation: always use RGB 4:4:4 codecs or capture raw when shooting for HDR, and avoid Y’CbCr 4:2:2 codecs. If a codec doesn’t specify that it is “4:4:4” then it uses Y’CbCr encoding, and should be avoided.

On a side note, we briefly flirted with the HDR P3 Broadcast preset and S-Gamut3.Cine in DaVinci Resolve last week, but quickly realized the vectorscope was behaving erratically and colors were wacky, so we abandoned that idea right away. Still, we encourage readers to go ahead and play with the presets and input color spaces themselves to see firsthand how those settings affect the color of their project and the behavior of the scopes, and even export a short clip to verify that it reads BT.2020 PQ – confirmation that it meets YouTube’s requirements.

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