Steve Yedlin

His previous stuff is so interesting and it's very refreshing to see a Hollywood professional able to dig so deep into those topics and teach us about it https://yedlin.net/NerdyFilmTechStuff/index.html

I think the point that SDR inputs (to a monitor) can be _similar_ to HDR input to monitors that have high dynamic ranges is obvious if you look at the maths involved. Higher dynamic gives you more precision in the information, you can choose to do what you want with it : higher maximum luminosity, better blacks with less noise, more details in the middle etc.

Of course we should also see "HDR" as a social movement, a new way to communicate between engineers, manufacturers and consumers, it's not "only" a math conversion formula.

I believe we could focus first on comparing SDR and HDR black and white images, to see how higher dynamic range only in the luminosity is in itself very interesting to experience

But in the beginning he is saying the images look similar on both monitors. Surely we could find counter examples and that only applies to his cinema stills ? If he can show this is true for all images then indeed he can show that "SDR input to a HDR monitor" is good enough for all human vision. I'm not sure this is true, as I do psychedelic animation I like to use all the gamut of colors I have at my hand and I don't care about representing scenes from the real world, I just want maximum color p0rn to feed my acid brain : 30 bits per pixels surely improve that, as well…

Thanks for weighing in with real-world experience doing film scans.

> From my experience, 4K was the absolute edge you could pull from the best 35mm films... I managed to pull 8K from some 70mm ride footage.

This matches the expert opinion I've heard elsewhere, as well as what was done when scanning Blade Runner (an historically important film now in the national archives). They scanned the 35mm camera negatives at 4K and the 65mm VFX camera negatives at 8k. I'd add that in film scanning, extended color depth is also very important to capturing the full fidelity of what's on the celluloid. An adjacent high-impact factor is how the grain structure of film is handled in post-scan processing. This entails artfully balancing a tricky set of trade-offs because the highest-frequency edge and chroma details are down in the noise floor. Extracting more signal is a knife-edge balance between amplifying noise on one side or suppressing filmic texture on the other. Ultimately, these choices move beyond technical correctness to aesthetic judgement, which I imagine has to be the sweat-inducing part of the job. Anyone really interested in resolution, film scanning and digital cinema should see this in-depth comparison shot by an expert ASC cinematographer specifically to be a definitive set of proofs for the industry. He compares (and pixel-peeps) identical shots from a range of top digital cinema cameras (Arri Alexa, RED, etc) with a high-quality 6K film scan.…

I'm not sure if it's because of growing up watching most things online with limited bitrates, but I realized I dislike film grain a lot. I know that to a certain degree, film grain helps humans resolve finer details. Similar to using noise shaped dithering to allow you to hear more than the theoretical dynamic range in audio or see a larger range of color tones in a picture. But I found that on certain 4K uhd blurays, if I am watching on a small screen the film grain looks very obnoxious. The problem doesn't exist when watching on a big TV, so I know it's not related to projecting on a screen. I really dislike when directors go out of their way to add artificial film grain. Will media players eventually allow users to adjust the film grain that is added back in?

This reminds me of Steve Yedlin's, cinematographer on everything from Brick to Star Wars: The Last Jedi to Knives Out and its 2022 sequel, Glass Onion: A Knives Out Mystery, who showed through research that film can be completely emulated using digital techniques and mixed digital and film shots during Star Wars.

https://www.audiocheck.net/audiotests_dithering.php

https://www.polygon.com/2020/2/6/21125680/film-vs-digital-debate-movies-cinematography

https://www.yedlin.net/NerdyFilmTechStuff/MatchLensBlur.html

https://www.yedlin.net/OnColorScience/index.html

Film is definitely still available, and you can use a target to as a starting point for a LUT, though the workflow is not straightforward. The core of the problem is that you're only sampling a fraction of the number of colors in the LUT, so to derive the rest of the LUT entries, you need to interpolate and extrapolate.

The trick is which algorithm you use to take the sparse 3D mesh of the calibration target and warp/interpolate the rest of the values. Trilinear would be the most naïve (and lowest quality) approach.

There's a ton more detail about how to actually match digital to film in Steve Yedlin's blog [1], including a cool video of sparse color interpolation in 3D (toward the bottom of the page).

[1] http://www.yedlin.net/NerdyFilmTechStuff/index.html

[2] http://www.yedlin.net/OnColorScience/index.html

thanks for your insights. my comment was overly cynical. in practice though visually , on a good (really good) monitor, you really can not see a difference. trained eyes, cannot really see a real difference. the difference becomes visible more due to a monitors own quircks not displaying accurately (mapping of this sdr/hdr to colourspace).

this was posted before here on HN and i dont think its wrong. though ofcourse, technically, there are differences, which might be in some applicaitons ( but usually are not) exploited to the viewers benefit. (?? maybe?? someone with real good eyes :)) https://yedlin.net/DebunkingHDR/index.html

maybe my interpretation is wrong, but i dont think it is far off if it is. specification differences and differences in human perception are not the same thing

That is not what Yedlin's tests show or made an effort to test! His famous first set of comparison tests are about resolution, specifically his opinions about the unimportance of 4K.

I deeply disagree with his conclusion, because he is downgrading a digital image to show it can match the resolution and some of the visual aspects of a 16 print. Which is like putting a filter over a high resolution monitor and then comparing it to SD TV.

But in either case, his work wasn't about whether digital could match the look of any film (it can't).

He has also never released his nuke workflow, although he's more recently productised it to some extent.

Here's his discussion of the footage you linked - https://www.yedlin.net/DisplayPrepDemo/DispPrepDemoFollowup