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8k 12k - some considerations for practical use

Top right Peter Swinson in 2007 and bottom right in Chicago when working for Bell & Howell, holding their Technical Oscar.










RAW Files are a clever idea that has also been developed by camera manufacturers to get the best possible image quality out of digital cameras while using the least amount of data.


Images from cameras that can shoot in raw are perfect for colour grading with Da Vinci Resolve as they contain all of the original highlight, lowlight, and mid-tone information, they enable the full image latitude and HDR, and yet the files are made of reasonable amounts of data.


Post production can be made simpler and more efficient by not converting files into other formats, and, indeed Resolve is an excellent example with its capability of being able to work directly in native raw files. Why transcode to any other format? Doing so would be a waste of time, a waste of space and also a waste of money, whilst it could also potentially degrade the image quality.


Grant Petty, CEO of Blackmagic Design on raw:


"Blackmagic RAW is a modern, high performance, professional RAW codec that is open, cross platform and free. It has been designed to provide the industry with an open, elegant and standardized high quality image format.”



4. Film Restoration in 8k with Pro Res XQ compression


Carefully controlled light compression schemes can also be applied to film originated materials as well as digital cameras, and which give the resulting 8k scanned, mastered and restored films an extremely impressive look. The standard 4k 16 bit DPX files that have been for the last decade the bench mark mastering format require a data rate of some 405 MBytes/sec in playback, whereas the same film scanned in 8k with Pro Res Raw XQ becomes a higher (but eminently manageable) amount of data, with an incredible increase in picture quality. In numbers, the maximum quality Pro Res XQ file of an 8k film at 24 fps. is 848 MBytes/sec. On the other hand, an uncompressed 8k 16 bit dpx file would be a whopping 8,018 MBytes/sec, or nearly 10 times as much data.


The point is that the 8k pro res XQ offers visually lossless compression, or, in other words a result indistinguishable from the uncompressed version, for a tenth of the amount of data.


Those that have not yet seen the kind of result possible with 8k scanning of films often state with conviction that 4k is “enough” for 35mm films. However, the Mobile Digital Lab pushes the benchmark from “enough” to "excellent", and for good reasons; the 8k pro res offers better imagery with more fine detail than 4k can offer. It shows a certain pristine quality while offering an analog style purity and subtlety, in what could also be defined as arguably better quality than projected positive prints can offer.


Using higher resolutions to shoot digitally and scan film offers, in our opinion, better image quality for the finished product, and now that the technology has become eminently enabling for 8k and beyond, there’s no excuse not to use it!! It will look better!! And it won’t cost more!! Indeed, with Mobile Digital Lab it will cost less!! And I haven't even mentioned the fact that shooting in 8k or 12k offers a certain degree of future proofing for the production...


Of course, productions are made of images and sound, so the mobile lab is designed to work for this too. Alberto Parodi, partner with his Logical Box in Genoa for sound also works initially where the production is being shot, and with portable units cleans up the raw audio takes, making ADR if necessary too, while synching the edit as it is being done.


80% of the film or episodic television’s edit, colour grade, visual effects and sound are ideally finished by the end of shooting, and, at that point are moved physically to the sound studios in Genoa for finalising.

 

5. Lossless - A type of codec for which putting an image through encoding followed by decoding results in an image that is mathematically guaranteed to have exactly the same pixel values as the original.


6. Visually lossless - A type of codec for which putting an image through encoding followed by decoding results in an image that is not mathematically lossless, but is visually indistinguishable from the original when viewed alongside the original on identical displays.



Early one afternoon some 30 years ago a young Peter Swinson, at the time part of the research department of telecine and scanner manufacturer Rank Cintel, demonstrated that the higher the resolution of scans, the more efficient compression became. In other words, using Peter's techniques we got smaller files, less data and yet higher quality pictures. Certainly, his work stimulated many of us to understand that compression and ultra high resolution would both become rather important interrelated issues from then on, as indeed they have done since.


Over the years, and making use of ever improved codecs, I’ve also come to the practical conclusion that small amounts of compression can be used effectively for mastering, editing, grading etc. in a pro-active way to reduce costs, while also reducing storage requirements and processing power of equipment. This can be done with no degradation at all in the quality of the images, as long as lossless compression is used, because this is mathematically guaranteed to have exactly the same pixel values as the original.


1. The theory of compression with high resolution images.

2. Oversampling.

The practise of oversampling, or using higher resolutions than the deliverable format to shoot digitally and scan film offers better image quality for the finished product, once down-rezzed. It is also worth noting that using oversampling and compression render remote working eminently more efficient as the resulting reduced data rates mean faster transfer times over the internet.  


It is often thought that remote work is only possible in large cities with fibre optic cables, but as has already been experienced during the spring of 2020 in full lock down by partner Alessio Focardi of Florence based Sartoria Immagine, for those with adequate software and hardware it is easily possible to receive directly from the set 8K Raw with a 4G + LTE connection, even when living in the countryside.




Based on Mike Connor's and my collective professional experiences during 2020 we have designed a Mobile Digital Lab that functions both as a complete DIT workstation and as a creative editorial hub with on line editing, colour grading, sound and visual effects in the final deliverable quality resolution. It is the equivalent of a fully fledged post production facility that can be set up in less than an hour physically near where shooting is on going, or even directly inside a film studio. It offers a simple, practical, cost effective and fast workflow for finishing high resolution films and episodic television series.
























With the Mobile Digital Lab we can shorten the time normally required for delivery of finished product when using today’s off line / on line and multi format editing workflow, while also offering a high degree of quality control and peace of mind over and during the production's progress.


Using the lab, graded dailies with synched audio are produced and shown to the director and production as they are shot and processed, complete with visual effects. Being able to view HDR 6k reference images within a calibrated environment helps decision making for the entire crew, from director and producer, heads of departments, production design, make up, hair, costumes; all have much to gain viewing and checking their work on the ultra high resolution calibrated display of the lab, and which gives a precise rendition of what we are going to get in the final master.

 

As an experienced visual effects supervisor I can say that I often felt that I had my eyes blindfolded in the past as I could usually only see months later elements shot for visual effects composited together. With the mobile lab, I can now see the composites of these elements almost immediately, at least for circled takes, and, in general, the capability of the lab to work on visual effects as they are shot helps to improve the quality of the results, with the added advantage that if all is not working, then elements can be re-shot there and then. From green and blue screens, tracking, stabilisation, re-framing and more, the use of 8k and 12k imagery for these adds image quality to the composites. Indeed, grading in these resolutions offers an incredible and absolutely unique selectivity for colours and, at the same time, less image noise, especially in the lowlights.

 

Compression can also be applied to 8k scanned film negatives, as this offers better imagery with more fine detail than in the current mastering process of 4k. Not surprisingly 8k shows a higher pristine quality and fine grain detail than 4k while offering an analog style purity and subtlety, in what could also be defined as arguably better quality than projected positive prints are able to offer. The higher resolution works pro-actively for the digital correction of analogue film defects, and advances in computing power with artificial intelligence will make this process ever faster.  

3.  8k 12k Mobile Digital Lab.

.6    Below, Blackmagicdesign Ursa Mini Pro.