6 minute read
AJA CION: No need to grade
RedShark replay: Could cameras like the AJA CION usher in a return to capturing great images in-camera? Simon Wyndham investigates.
At the recent Broadcast Video Expo in London, I recently had a rather fascinating conversation with the guys at AJA about the CION camera that has just been released. It was enlightening because I was given some interesting facts about sensor production and the way they arrive at "native" ISO figures (the long and short of it: there is no such thing as a "native" ISO for a sensor), along with a number of other things. We will be reviewing the CION in the near future, but AJA's demonstration of the CION got me thinking about how we approach the look of a picture.
The world is flat
These days, all the talk is of Log gamma, RAW and grading in packages such as Blackmagic Design's DaVinci Resolve. The education now available for picture grading and free software is incredible compared to just a few years ago. Grading and colourisation, processes that were once reserved for only those productions with the budget to do so, is now used routinely, even on the lowest budget corporate productions.
With pressure to reduce freelance rates, the grading process is yet another chain in the workflow and possibly one that has run away with itself. Shooting flat to decide a look later is now so commonplace that many people shoot in such modes routinely. In fact, the idea of "baking in" a look at the point of shooting can sometimes be frowned upon. "OMG what if you need to adjust it later?!" come the cries!
However, there's no need to panic about this.
The good old days
There was a time when everything was shot to look good right out of the camera. This goes for both video and film. There is a real skill and confidence involved in deciding on a look from the outset and creating it with the use of lighting, both natural and artificial, and glass filters.
With film, there was a choice of film stock, while with video we could adjust picture profiles and colour matrixes. Sony video cameras were always known to produce accurate colour out of the box, but often required engineering setup to get what most people would call a pleasing looking picture, rather than merely a technically accurate one. Panasonic cameras looked great right out of the box, for the most part. Anyone who remembers the SDX900 will recall how much it loved reds.
Those with attention to detail will inform me that film sometimes went through processes to adjust the look during development or during telecine, etc. This is true, but for many productions the majority of the look was generally created in-camera, even though the option of chemical processes was also available.
AJA CION: Stellar at Capture
How does all of this relate to the CION? The fascinating thing about the demonstration I was given was that although it was possible to shoot with the "flat" look, if that's what you wanted to do, the camera was mostly being demonstrated as a device that can capture an amazing looking picture right out of the box, with gloriously accurate skin tones, deep blacks, lots of highlight detail and accurate, but deep colour. Apparently, the boffins at AJA have been working hard to fine tune the picture since the initial release of demo footage a few months back.
I'm looking forward to seeing how this plays out and whether we might see a return to shooting great looking footage right out of the camera. The AMIRA and the ALEXA, cameras that AJA hopes that the CION will compliment, are both capable of producing a wonderful looking picture straight out of the box, should they be required to do so.
Grading matters
When it comes to grading, the elephant in the room is that in order to obtain the best results from the enormous dynamic range that modern camcorders are capable of recording, the user needs a good deal of knowledge, time and skill when using the grading software.
There are many people who use filters like Film Convert. These plugins are certainly capable of great results, most of which are designed to replicate ungraded film stocks. Quite an irony! This points to the fact that there is something about the way film reproduces colour that we love that traditional video cameras cannot reproduce.
But these days, our cameras are a lot more capable than those of old. Gone are the days of being worried about going above 9db of gain for fear of noise or having to ramp up the digital edge enhancement. In fact, ever since the F900 (and at a lower level, the EX1/3), we have been able to dial down the digital edge enhancement right down to zero for more natural looking images, while still showing true high resolution pictures.
Thanks, Alan
Some manufacturers still cling to shipping their cameras with a load of edge enhancement dialed in when, frankly, the camera doesn't need it. Alan Roberts, a BBC video engineer who was often commissioned to research and develop picture profiles for individual cameras, replicating the more natural look of film after it had gone through a "best light" telecine process. Roberts was the first to advocate the flat picture setup.
His settings, based on deep research into the differences between film and video motion, as well as dynamic range, paved the way to where we are today. Part of that research is often overlooked - that of picture motion differences and characteristics. Roberts discovered that one of the reasons why progressive scan video looked more juddery than film was because of the way detail frequencies were being handled by the two mediums.
Film is great at showing high frequency detail, such as fine hair or the high contrast edges of buildings against a sky for instance, but less so with low to medium frequency detail, such as the subtle coloured patterning on leaves. When an edge or a detail has a hard contrast, that area of the picture appears to judder more.
Because most video cameras traditionally ship pre-set with digital edge enhancement at a blanket level that covers not only high frequency detail, but also the mid frequency detail, video generally appears to judder more, because much more of the picture area has higher contrasting detail, due to the detail enhancement setting.
Alans’ settings sought primarily to adjust the detail, coring and levels at a point that would enhance the high frequencies while toning down the effect on the mid and lower detail frequencies.
Setting it down flat
As better cameras came along, many of his settings recommended turning off the detail enhancement circuits altogether or even setting them at a negative setting. Cameras such as those from Blackmagic have no detail enhancement to my knowledge, giving a much more natural result. Most of the modern Sony cameras are perfectly capable of resolving a sharp UHD, 4K or HD image without need for additional help.
Alan's settings also, importantly, covered the black gamma levels and knee circuits in such a way as to obtain as much range off the sensor as possible onto the recorded medium. This often resulted in a quite flat looking picture that required grading.
Sony eventually released their Hypergammas onto their HDCAM range, before these filtered down to their lower end HD cameras as the years passed. Digital Praxis also released some highly praised gamma curve settings for the HDCAM cameras.
As Sony, JVC, and Panasonic started to include more settings on their cameras, people began to experiment with different picture profiles. This often involved trying to achieve a good look straight out of the camera, but it also paved the way for Alan Roberts to devise film like settings for these cameras as well.
Exceeding limits?
Grading the picture gradually started to become more common and reached a height when various flat profiles were released for DSLRs, such as the Canon 5D Mk2 and the like.
Despite the fact that many of these cameras recorded to highly compressed 8-bit 4:2:0 or 4:1:1 MPEG formats, this didn’t deter people from attempting to heavily grade such footage, regardless of the noise and colour banding that was introduced. But it seems it didn't matter, because with the software available, we could all now speak the same jargon as the big Hollywood studios!
However, modern cameras are now much more sophisticated. Devices routinely record to 10-bit 4:2:2 intra-frame formats out of the box, with many offering a RAW recording option as well.
A better path
Personally, I don't want to be forced into heavy grading. It adds time to a project that should be billed for. But I can sympathise because trying to explain and sell "grading" to a corporate client is not exactly an easy thing to do. In fact, it is something that most marketing execs couldn’t really care less about! "Can you do the job or not?"
Therefore, a lot of content producers out there take the time to go through a grading process with minimal additional income for their trouble, simply because they want the best out of the picture and they feel that they should.
As cameras such as the CION should prove, it doesn’t need to be this way. You can get an amazing picture out of the box and I think that it is about time this way of thinking made a comeback. Yes, you may need to do the odd simple colour or exposure match, but if new cameras come set with a much more natural, filmic looking picture right out of the box, it could save us all a lot of time and effort for jobs that do not have the time or budget for messing around with (or skillfully performing) grading.
Alan Roberts excellent "Film Look, it’s not just jerky motion" paper that he wrote for the BBC can be read HERE.
Tags: Production
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