Comment by davidferguson

TL;DR: Linking to YouTube trailer scans as comparisons for colour is misleading and not accurate.

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> see the 35 mm trailer for reference

The article makes heavy use of referring to scans of trailers to show what colours, grain, sharpness, etc. looked like. This is quite problematic, because you are replying on a scan done by someone on the Internet to accurately depict what something looked like in a commercial cinema. Now, I am not a colour scientist (far from it!), but I am a motion picture film hobbyist and so can speak a bit about some of the potential issues.

When projected in a movie theatre, light is generated by a short-arc xenon lamp. This has a very particular output light spectrum, and the entire movie process is calibrated and designed to work with this. The reflectors (mirrors) in the lamphouse are tuned to it, the films are colour graded for it, and then the film recorders (cameras) are calibrated knowing that this will be how it is shown.

When a film is scanned, it is not lit by a xenon short-arc lamp, instead various other illumination methods are used depending on the scanner. CRTs and LEDs are common. Commercial scanners are, on the whole, designed to scan negative film. It's where the money is - and so they are setup to work with that, which is very different to positive movie release film stock. Scanners therefore have different profiles to try and capture the different film stocks, but in general, today's workflow involves scanning something in, and then colour correcting post-scan, to meet an artist's expectations/desires.

Scanning and accurately capturing what is on a piece of film is something that is really quite challenging, and not something that any commercial scanner today does, or claims to do.

The YouTube channels referenced are FT Depot, and 35mm Movie Trailers Scans. FT Depot uses a Lasergraphics 6.5K HDR scanner, which is a quite high end one today. It does have profiles for individual film stocks, so you can set that and then get a good scan, but even the sales brochure of it says:

> Many common negative film types are carefully characterized at Lasergraphics to allow our scanning software to compensate for variation. The result is more accurate color reproduction and less time spent color grading.

Note that it says that less time is spent colour grading - it is still not expected that it will accurately capture exactly what was on the film. It also specifies negative, I don't know whether it has positive stock profiles as I am not lucky enough to have worked with one - for this, I will assume it does.

The "scanner" used by 35mm Movie Trailers Scans is a DIY, homemade film scanner that (I think, at least the last time I spoke to them) uses an IMX-183 sensor. They have both a colour sensor and a monochrome sensor, I am not sure what was used to capture the scans linked in the video. Regardless of what was used, in such a scanner that doesn't have the benefit of film stock profiles, etc. there is no way to create a scan that accurately captures what was on the film, without some serious calibration and processing which isn't being done here. At best, you can make a scan, and then manually adjust it by eye afterwards to what you think looks good, or what you think the film looks like, but without doing this on a colour calibrated display with the original projected side-by-side for reference, this is not going to be that close to what it actually looked like.

Now, I don't want to come off as bashing a DIY scanner - I have made one too, and they are great! I love seeing the scans from them, especially old adverts, logos, snipes, etc. that aren't available anywhere else. But, it is not controversial at all to say that this is not colour calibrated in any way, and in no way reflects what one actually saw in a cinema when that trailer was projected.

All this is to say that statements like the following in the article are pretty misleading - as the differences may not be attributable to the direct-digital-release process at all, and could just be that a camera white balance was set wrong, or some post processing to what "looked good" came out different to the original:

> At times, especially in the colors, they’re almost unrecognizable

> Compared to the theatrical release, the look had changed. It was sharp and grainless, and the colors were kind of different

I don't disagree with the premise of the article - recording an image to film, and then scanning it in for a release _will_ result in a different look to doing a direct-digital workflow. That's why major Hollywood films spend money recording and scanning film to get the "film look" (although that's another can of worms!). It's just not an accurate comparison to put two images side by side, when one is of a trailer scan of unknown accuracy.