Sony’s Pro Tour is visiting Oslo, Norway on the 8th of March 2018. At this event there will be the opportunity to see some of Sony latest video production kit including cameras from the handheld range like the PXW-FS7M2, PXW-FS5, PXW-Z90 as well as a large range of monitors, vision mixers and related video production technology.
There will be 4 different product areas as follows:
Large Format Sensor
Showing PXW-FS7 II, FS7 & FS5
4K HDR Production
Showing PXW-Z90, PXW-Z150 & HXR-NX80 (TBC)
Showing PXW-X70, PXW-X200, HXR-NX100
Live Event Production
Showing MCX-500, RM-30BP, HXR-NX5R, SRG-360, RM-IP10 and an RX0
As well as the exhibits there will be a seminar “HDR for all” from Alister Chapman with some great information on what HDR is, what you can expect from it and how you can use Sony’s cameras to create instant HDR content.
Admission is free. For more information and to register please CLICK HERE.
I’ve been shooting with the Fujinon MK18-55mm lens on my PXW-FS7 and PXW-FS5 since the lens was launched. I absolutely love this lens, but one thing has frustrated me: I really wanted to be able to use it on my PMW-F5 to take advantage of the 16 bit raw. Finally my dreams have come true as both Duclos and MTF have started making alternate rear mounts for both the MK18-55mm and the MK50-135mm.
So, when Fujinon contacted me and asked if I would be interested in shooting a short film with these lenses on my F5 I jumped at the chance. The only catch was that this was just over a week ago and the video was wanted for IBC which means it needed to be ready yesterday. And of course it goes without saying that it has to look good – no pressure then!
First challenge – come up with something to shoot. Something that would show off the key features of these beautiful lenses – image quality, weight, macro etc. I toyed with hiring a model and travelling to the Irish or Welsh coast and filming along the cliffs and mountains. But it’s the summer holidays so there was a risk of not being able to get an isolated location all to ourselves, plus you never know what the weather is going to do. In addition there was no story, no beginning, middle or end and I really wanted to tell some kind of story rather than just a montage of pretty pictures.
So my next thought was to shoot an artist creating something. I spent a weekend googling various types of artistry until I settled on a blacksmith. The video was going to be shown in both SDR and HDR and fire always looks good in HDR. So after dozens of emails and telephone calls I found an amazing looking metalwork gallery and blacksmith that was willing for a reasonable fee to have me and another cameraman take over their workshop for a day (BIG thank you to Adam and Lucy at Fire and Iron check out their amazing works of art).
Normally I’d carry out a recce of a location before a shoot to take photos and figure out what kind of lights I would need as well as any other specialist or unusual equipment. But this time there simply wasn’t time. We would be shooting the same week and it was already a very busy week for me.
The next step before any shoot for me is some degree of planning. I like to have a concept for the video, at the very least some outline of the shots I need to tell the story, perhaps not a full storyboard, but at least some kind of structure. Once you have figured out the shots that you want to get you can then start to think about what kind of equipment you need to get those shots. In this case, as we would be shooting static works of art I felt that having ways to move the camera would really enhance the video. I have a small Jib as well as some track and a basic dolly that is substantial enough to take the weight of a fully configured PMW-F5 so these would be used for the shoot (I’m also now looking for a slider suitable for the F5/F55 that won’t break the bank, so let me know if you have any recommendations).
So the first items on my kit list after the camera and lenses (the lenses were fitted with Duclos FZ rear mounts) was the jib and dolly. To achieve a nice shallow depth of field I planned to shoot as close to the lenses largest aperture of T2.9 as possible. This presents 2 challenges. The F5’s internal ND filters go in 3 stop steps – that’s a big step and I don’t want to end up at T5.6 when really I want T2.9, so 1 stop and 2 stop ND filters and my gucchi wood finished Vocas matte box would be needed (the wood look does nothing to help the image quality, but it looks cool). Oh for the FS7 II’s variable ND filter in my F5!
The second problem of shooting everything at T2.9 with a super 35mm sensor is that focus would be critical and I was planning on swinging the camera on a jib. So I splashed out on a new remote follow focus from PDMovie as they are currently on offer in the UK. This is something I’ve been meaning to get for a while. As well as the remote follow focus I added my Alphatron ProPull follow focus to the kit list. The Fujinon MK lenses have integrated 0.8 pitch gears so using a follow focus is easy. I now wish that I had actually purchased the more expensive PDMovie follow focus kit that has 2 motors as this would allow me to electronically zoom the lens as well as focus it. Oh well, another thing to add to my wish list for the future.
One other nice feature of the Fujinon MK’s is that because they are parfocal you can zoom in to focus and then zoom out for the wider shot and be 100% sure that there is no focus shift and that the image will be tack sharp. Something you can’t do with DSLR lenses.
Lighting: This was a daylight shoot. Now I have to say that I am still a big fan of old school tungsten lighting. You don’t get any odd color casts, it gives great skin tones, it’s cheap and the variety and types of lamp available is vast. But as we all know it needs a lot of power and gets hot. Plus if you want to mix tungsten with daylight you have to use correction gels which makes the lights even less efficient. So for this shoot I packed my Light and Motion Stella lamps.
The Stellas are daylight balanced LED lamps with nice wide 120 degree beams. You can then use various modifiers to change this. I find the 25 degree fresnel and the Stella 5000 a particularly useful combination. This is the equivalent to a 650W tungsten lamp but without the heat. The fresnel lens really helps when lighting via a diffuser or bounce as it controls the spill levels making it easier to control the overall contrast in the shot. The Stella lights have built in batteries or can be run from the mains. They are also waterproof, so even if it rained I would be able to have lights outside the workshop shining in through the windows if needed.
I always carry a number of pop-up diffusers and reflectors of various sizes along with stands and arms specifically designed to hold them. These are cheap but incredibly useful. I find I end up using at least one of these on almost every shoot that I do. As well as a couple of black flags I also carry black drapes to place on the floor or hang from stands to reduce reflections and in effect absorb unwanted light.
To check my images on set I use an Atomos Shogun Flame. Rather than mounting it on the camera, for this shoot I decided to pack an extra heavy duty lighting stand to support the Shogun. This would allow my assistant to use the flame to check focus while I was swinging the jib. The HDR screen on the Shogun allows me to see a close approximation of how my footage will look after grading. It also has peaking and a zoom function to help with focussing which was going to be essential when the camera was up high on the jib and being focussed remotely. I also included a TV-Logic LUM171G which is a 17″ grading quality monitor with 4K inputs. The larger screen is useful for focus and it’s colour accuracy helpful for checking exposure etc.
For audio I packed my trusty UWP-D wireless mic kit and a pair of headphones. I also had a shotgun mic and XLR cable to record some atmos.
As well as all the larger items of kit there’s also all the small bits and bobs that help a shoot go smoothly. A couple of rolls of gaffer tape, crocodile clips, sharpies, spare batteries, extension cables etc. One thing I’ve found very useful is an equipment cart. I have a modiffied rock-n-roller cart with carpet covered shelves. Not only does this help move all the kit around but it also acts as a desk on location. This is really handy when swapping lenses or prepping the camera. It can save quite a bit of time when you have a mobile work area and somewhere you can put lenses and other frequently used bits of kit.
The day before the shoot I set everything up and tested everything. I checked the backfocus adjustment of the lenses. Checked the camera was working as expected and that I had the LUT’s I wanted loaded into both the camera and the Gratical viewfinder. With the camera on the jib I made sure I had the right weights and that everything was smooth. I also checked that my light meter was still calibrated against the camera and that the lens apertures matched what I was expecting (which they did perfectly). Color temperature and colorimetry was checked on the TVLogic monitor.
It’s worth periodically checking these things as there would be nothing worse than rocking up for the shoot only to find the camera wasn’t performing as expected. If you rent a cinema camera package from a major rental house it would be normal to set the camera up on a test bench to check it over before taking it away. But it’s easy to get lazy if it’s your own kit and just assume it’s all OK. A full test like this before an important shoot is well worth doing and it gives you a chance to set everything up exactly as it will be on the shoot saving time and stress at the beginning of the shoot day.
On the morning of the shoot I loaded up the car. I drive a people carrier (minivan to my friends in the USA). Once you start including things like a jib, track and dolly, equipment cart, 6x tungsten lights, 4 x LED lights, plus camera, tripods (including a very heavy duty one for the jib) the car soon fills up. A conventional saloon would not be big enough! One word of caution. I was involved in a car crash many years ago when the car rolled over. I had camera kit in the back of the car and the heavy flight cases did a lot of damage crashing around inside the car. If you do carry heavy kit in the car make sure it’s loaded low down below the tops of the seats. You don’t want everything flying forwards and hitting you on the back of your head in a crash. Perhaps consider a robust steel grill to put between the cargo compartment and the passenger compartment.
On arrival at the location, while it’s very tempting to immediately start unloading and setting up, I like to take a bit of a break and have a tea or coffee first. I use this time to chat with the client or the rest of the crew to make sure everyone knows what’s planned for the day. Taking a few minutes to do this can save a lot of time later and it helps everyone to relax a little before what could be a busy and stressful day.
Now it’s time to unpack and setup. I find it’s better to unpack all the gear at this time rather than stopping and starting throughout the day to unpack new bits of kit. Going to the car, unlocking, unpacking, locking, back to the set etc wastes time. This is where the equipment cart can be a big help as you can load up the cart with all those bits and pieces you “might” need… and inevitably do need.
The blacksmiths workshop was a dark space about 6m x 5m with black walls, open on one side to the outside world. Blacksmiths forges (so I learnt) are dark so that the blacksmith can see the glow of the metal as it heats up to gauge it’s temperature. On the one hand this was great – huge amounts of relatively soft light coming from one direction. On the other hand the dark side was very dark which would really push the camera and lenses due to the extreme contrast this would create.
We set the jib up inside the workshop to shoot the various processes used by a blacksmith when working with iron and steel. Apparently there are only 7 different processes and anything a blacksmith does will use just these 7 processes or variations of them.
Most of the shots done on the jib would be shot using the Fujinon MK18-55mm, so that’s the lens we started with. For protection from flying sparks a clear glass filter was fitted to the lens. While the finished film would be a 24p film, most of the filming was 4K DCI at 60fps recording to 16 bit raw. This would give me the option to slow down footage to 24p in post if I wanted a bit of slow motion.
When we did need to do a lens swap it was really easy. The Vocas matte box I have is a swing-away matte box. So by releasing a lever on the bottom of the matte box it swings out of the way of the lens without having to remove it from the rods. Then I can remove the lens and swap it to the other lens. The MK50-135mm is the same size as the MK18-55mm. The pitch gears are also in the same place. So swapping lenses is super fast as the follow focus or any focus motors don’t need to be re-positioned and the matte box just swings back to exactly the same position on the lens. It’s things like this that really separate pro cinema lenses from DSLR and photography lenses.
For exposure I used the cameras built in LUT’s and the 709(800) LUT. I set the camera to 800EI. I used a grey card to establish a base exposure, exposing the grey card at 43% (measuring the 709 level). I used a Zacuto Gratical viewfinder which has a great built in waveform display, much better than the one in the camera. I also double checked my light levels with a light meter. I don’t feel that it’s essential to use a light meter but it’s a useful safety net. The light meter is also handy for measuring contrast ratios across faces etc but again if you have a decent waveform display you don’t have to have a light meter.
For the next 3 hours we shot the various processes seen in the video. Trying to get a variety of different shot. But when each process is quite similar, usually involving the anvil and a large hammer it was difficult to come up with shots that looked different.
In the afternoon we set up to shoot the interview sequence. The reason for doing this was to not only provide the narrative for the film but also to help show how the lenses reproduce skin tones. The Fujinon MK series lenses are what I would describe as “well rounded”. That is, not too sharp but not soft either. They produce beautifully crisp pictures without the pictures looking artificially sharp and this really helps when shooting people and faces. They just look really nice.
For the interview shot I used one of the Stella 5000 lights with the 25 degree fresnel lens aimed through a 1m wide diffuser to add a little extra light to supplement the daylight. This allowed me to get some nice contrast across the blacksmiths face and nice “catch light” highlights in his eyes. In addition the little bit of extra light on his face meant that the back wall of the forge would appear just that bit darker due to the increased contrast between his face and the back wall. This is why we light…. not just to ensure enough light to shoot with, I had plenty of light, if I remember right I had a 1 stop ND in the matte box. But to create contrast, it’s the contrast that gives the image depth, it’s contrast that makes an image look interesting.
The final stage was to shoot the treasure chest and ornate jars that would show off the the lenses macro and close up performance. The treasure chest is a truly amazing thing. It weighs around 80kg. The locking mechanism is quite fascinating and I still struggle to believe that it was all hand made. The small metal jars are made out of folded and welded steel. It’s the folds in the metal that create the patterns that you see.
Once again we used the jib to add motion to the shots. I also used the macro function of both the MK18-55mm and MK50-135mm lenses. This function allows you to get within inches of the object that you are shooting. It’s a great feature to have and it really adds to the versatility of these lenses.
We wrapped at 7pm. Time to pack away the kit. It’s really important not to rush at this stage. Like everyone else I want to get home as quick as I can. But it’s important to pack your kit carefully and properly. There is nothing more annoying than when you start prepping for the next shoot finding that something has been broken or is missing because you rushed to pack up at the end of the previous shoot. Once you have packed everything away don’t forget to do that last walk through all the locations you’ve shot in to make sure you haven’t forgotten something.
I shot a little over hour of material. As it was mostly 60p 4K raw that came to about 1.5TB This was backed up on site using a Nexto-DI NSB25 which is a stand alone device that makes 2 verified copies of everything on 2 different hard drives. The film was edited using Adobe Premiere CC which handles Sony’s raw very easily. Grading was completed using DaVinci Resolve. I spent 2 days editing and a day grading the first version of the film. Then I spent another day re-grading it for HDR and producing the different versions that would be needed. All in, including coming up with the concept, finding the location, prepping, shooting and post took it took about 7 to 8 full work days to put this simple 4 minute film together.
While we wait for Sony to re-release the version 4 firmware for the FS5 I thought I would briefly take a look at what HLG is and what it’s designed to do as there seems to be a lot of confusion.
HLG stands for Hybrid Log Gamma. It is one of the gamma curves used for DISTRIBUTION of HDR content to HDR TV’s that support the HLG standard. It was never meant to be used for capture, it was specifically designed for delivery.
As the name suggests HLG is a hybrid gamma curve. It is a hybrid of Rec-709 and Log. But before you get all excited by the log part, the log used by HLG is only a small part of the curve and it is very agressive – it crams a very big dynamic range into a very small space – This means that if you take it into post production and start to fiddle around with it there is a very high probability of problems with banding and other similar artefacts becoming apparent.
The version of HLG in the FS5 firmware follows the BBC HLG standard (there is another NHK standard). From black to around 70% the curve is very similar to Rec 709, so from 0 to 70% you get quite reasonable contrast. Around 70% the curve transitions to a log type gamma allowing a dynamic range much greater than 709 to be squeezed into a conventional codec. The benefit this brings is that on a conventional Rec-709 TV the picture doesn’t look wrong. It looks like a very slightly darker than normal, only slightly flat mid range, but the highlights are quite flat and washed out. For the average home TV viewer watching on a 709 TV the picture looks OK, maybe not the best image ever seen, but certainly acceptable.
However feed this same signal to an HDR TV that supports HLG and the magic starts to happen. IF the TV supports HLG (and currently only a fairly small proportion of HDR TV’s support HLG. Most use PQ/ST2084) then the HLG capable HDR TV will take the compressed log highlight range and stretch it out to give a greater dynamic range display. The fact that the signal gets stretched out means that the quality of the codec used is critical. HLG was designed for 10 bit distribution using HEVC, it was never meant to be used with 8 bit codecs, so be very, very careful if using it in UHD with the FS5 as this is only 8 bit.
So, HLG’s big party trick is that it produces an acceptable looking image on a Rec-709 TV, but also gives an HDR image on an HDR TV. So one signal can be used for both HDR and SDR giving what might be called backwards compatibility with regular SDR TV’s. But it is worth noting that on a 709 TV HLG images don’t look as good as images specifically shot or graded for 709. It is a bit of a compromise.
What about the dynamic range? High end HDR TV’s can currently show about 10 stops. Lower cost HDR TV’s may only be able to show 8 stops (compared to the 6 stops of a 709 TV). There is no point in feeding a 14 stop signal to a 10 stop TV, it won’t look the best. From what I’ve seen of the HLG curves in the FS5 they allow for a maximum of around 10 to 11 stops, about the same as the cinegammas. HLG can be used for much greater ranges, but as yet there are no TV’s that can take advantage of this and it will be a long tome before there are. So for now, the recorded range is a deliberately limited so you don’t see stuff in the viewfinder that will never be seen on todays HDR TV’s. As a result the curves don’t use the full recording range of the camera. This means they are not using the recording data in a particularly efficient way, a lot of data is unused and wasted. But this is necessary to make the curves directly compatible with an HLG display.
What about grading them? My advice – don’t try to grade HLG footage. There are three problems. The first is that the gamma is very different in the low/mid range compared to the highlights. This means that in post the shadows and mid range will respond to corrections and adjustments very differently to the high range. That makes grading tricky as you need to apply separate correction to the midrange and highlights.
The second problem is that the is a very large highlight range squeezed into a very small recording range. It should look OK when viewed directly with no adjustment. But if you try stretching that out to make the highlights brighter (remember they never reach 100% as recorded) or to make them more contrasty, there is a higher probability of seeing banding artefacts than with any other gamma in the camera.
The third issue is simply that the limited recording range means you have fewer code values per stop than regular Rec-709, the cinegammas or S-Log2. HLG is the least best choice for grading in the FS5.
Next problem is color. Most HDR TV’s want Rec-2020 color. Most conventional monitors want Rec-709 color. Feed Rec-2020 into a 709 monitor and the colors look flat and the hues are all over the place, especially skin tones. Some highly saturated colors on the edge of the color gamut may pop out more than others and this looks odd.
Feed 709 into a 2020 TV and it will look super saturated and once again the color hues will be wrong. Also don’t fool yourself into thinking that by recording Rec2020 you are actually capturing more. The FS5 sensor is designed for 709. The color filters on the sensor do work a little beyond 709, but nowhere near what’s needed to actually “see” the full 2020 color space. So if you set the FS5 to 2020 what you are capturing is only marginally greater than 709. All you really have is the 709 with the hues shifted and saturation reduced so color looks right on a 2020 monitor or TV.
So really, unless you are actually feeding an Rec 2100 (HLG + 2020) TV, there is no point in using 2020 color as this require you to grade the footage to get the colors to look right on most normal TV’s and monitors. As already discussed, HLG is far from ideal for grading, so better to shot 709 if that’s what your audience will be using.
Don’t let the hype and fanfares that have surrounded this update cloud your vision. HLG is certainly very useful if you plan to directly feed HDR to a TV that supports HLG. But if you plan on creating HDR content that will be viewed on both HLG TV’s and the more common PQ/ST2084 TV’s then HLG is NOT what you want. You would be far – far better off shooting with S-Log and then grading your footage to these two very different HDR standards. If you try to convert HLG to PQ it is not going to look nearly as good as if you start with S-Log.
Exposure levels: If you want to get footage that works both with an HLG HDR TV and a SDR 709 TV then you need to expose carefully. A small bit of over exposure wont hurt the image when you view it on a 709 TV or monitor, so it will look OK in the viewfinder. But on an HDR TV any over exposure could result in skin tones that look much too bright and an image that is unpleasantly bright. As a guide you should expose diffuse 90% white (a white card or white piece of paper) at no more than 75%. Skin tones should be around 55 to 60%. You should not expose HLG as brightly as you do Rec-709.
Sure you can shoot with HLG for non HDR applications. You will get some slightly flat looking footage with rolled off highlights. If that’s the image you want then I’m not going to stop you shooting that way. If that’s what you want I suggest you consider the Cinegamma as these capture a similar DR also have a nice highlight roll off (when exposed correctly) and do use the full recording range.
Whatever you do make sure you understand what HLG was designed for. Make sure you understand the post production limitations and above all else understand that it absolutely is not a substitute for S-log.
Sony have today released firmware version 4.0 for the PXW-FS5. This firmware adds the ability to directly output Hybrid Log Gamma via picture profile 10 for an instant HDR workflow. It also allows you to set the base ISO for S-log to 2000 ISO.
Sony will be releasing an update for the firmware in the Sony PXW-FS5 in the next few days. This update amongst other things will allow users of the FS5 to shoot to HDR directly using the Hybrid Log Gamma HDR gamma curve and Rec2020 color. By doing this you eliminate the need to grade your footage and could plug the camera directly in to a compatible HDR TV (the TV must support HLG) and see an HDR image directly on the screen.
But what about FS7 and F5/F55 owners? Well, for most HDR productions I still believe the best workflow is to shoot in S-Log3 and then to grade the footage to HDR. However there may be times when you need that direct HDR output. So for the FS7, F5 and F55 I have created a set of Hybrid Log Gamma LUT’s that you can use to bake in HLG and Rec2020 while you shoot. This gives you the same capabilities as the FS5 (with the exception of the ability to add HLG metadata to the HDMI).
For a video explanation of the process please follow the link to my new Patreon page where you will find the video and the downloadable LUT’s.
The PXW-FS5 and PXW-Z150 will both get a free firmware update some time around June that will add the ability to shoot using a special gamma curve called “Hybrid Log Gamma” or HLG.
In the case of the FS5 this will be added through an additional picture profile, PP10. As well as HLG the camera will also have the ability to record using Rec2020 color. As a result the camera will become compatible with the new Rec2100 standard for HDR television.
In addition the FS5 will get the ability to change the base ISO for S-Log2 and S-Log3 from 3200 ISO to 2000 ISO. This will help produce cleaner images that are easier to grade. On top of that via a paid firmware update you will be able to shoot continuously at up to 120fps in full HD, no need to use the Super Slow Motion memory cache function.
These are all great upgrades for this little highly versatile camera.
By selecting Picture Profile 10 the camera will shooting using Hybrid Log Gamma. If you were to plug the camera into an HDR TV that supports HLG then what you would see on the TV would be a HDR image with an extended dynamic range. This should give brighter more realistic highlights and a quite noticeable increase in overall contrast compared to SDR (Standard Dynamic Range). There will be no need to grade the footage to get a perfectly watchable vibrant HDR image. The real beauty of HLG (developed by the BBC and NHK) is that it is backwards compatible with normal SDR (Standard Dynamic Range) TV’s. So feed the very same signal into a conventional SDR TV and it will look just fine. Skin tones will be a touch darker than with Rec709 and it won’t be HDR, but it will be perfectly watchable picture and most people won’t realise it’s anything different to normal SDR TV.
So HLG provides a simple very fast, direct HDR workflow that is backwards compatible with SDR TV’s. As a result you don’t need any special monitors to shoot with it, you can just monitor with existing SDR monitors, although it would be beneficial to have an HDR monitor to check the HDR aspect of the signal. HLG isn’t designed to be graded, although a little bit of post production tweaking can be applied, just as with Rec709. Bottom line is it’s quick and easy, no special monitors or skills needed – simples.
If you want the very best possible HDR then you should shoot with S-Log2/S-Log3 or raw and then grade the material in post using an HDR capable monitor. But that takes time and large HDR monitors are not cheap (for a small monitor you could use an Atomos Flame or Inferno). The FS5 will give you the ability to work either way. HLG for simple and quick, S-Log for the best possible image quality.
Hopefully we will see HLG rolled out to other cameras in the near future.
So, as you should have seen from my earlier post Sony has included Rec-2020 as a colorspace in custom mode on the new FS7 II. But what does this mean and how important is it? When would you use it and why?
Recommendation ITU BT.2020 is a set of standards created by the International Telecommunications Union for the latest and next generation of televisions. Within the standard there are many sub-standards that define things such as bit depth, frame size, frame rates, contrast, dynamic range and color.
The Rec-2020 addition in the the FS7 II specifically refers to the color space that is recorded, determining the range of colors that can be recorded and the code values used to represent specific tones/hues.
First of all though it is important to remember that the FS7 II shares the same sensor as the original FS7, the FS5 and F5. Sony has always stated that this sensor is essentially a “709” sensor. The sensor in Sony’s PMW-F55 can capture a much greater color range (gamut) than the F5, FS5 and FS7, only the F55 can actually capture the full Rec-2020 color space, the FS7 II sensor cannot. It’s very difficult to measure the full color gamut of a sensor, but from the tests that I have done with the F5 and FS7 I estimate that this sensor can capture a color gamut close to that of the DCI-P3 standard, so larger than Rec-709 but not nearly as large as Rec-2020 (I’d love someone to provide the actual color gamut of this sensor).
So given that the FS7 II’s sensor can’t actually see colors all that far beyond Rec-709 what is the point of adding Rec-2020 recording gamut as the camera can’t actually fill the recording Gamut? Similarly the F5/FS5/FS7 cannot fill S-Gamut or S-Gamut3.
The answer is – To record the colors that are captured with the correct values. If you capture using Rec-709 and then play back the Rec-709 footage on a Rec-2020 monitor the colors will look wrong. The picture will be over saturated and the hues slightly off. In order for the picture to look right on a Rec-2020 monitor you need to record the colors at the right values. By adding Rec-2020 to the FS7 II Sony have given users the ability to shoot Rec-2020 and then play back that content on a Rec-2020 display and have it look right. You are not capturing anything extra (well, maybe a tiny bit extra), just capturing it at the right levels so it at least looks correct.
As well as color, Rec-2020 defines the transfer functions, or gamma curves to you and me, that should be used. The basic transfer function is the same as used for Rec-709, so you can use Rec-709 gamma with Rec-2020 color to get a valid Rec-2020 signal. For full compatibility this should be 3840×2160 progressive and 10bit (the Rec-2020 standard is a minimum of 10bit and as well as 3840×2160 also includes 7680×4320).
But, one of the hot topics right now in the high quality video world is the ability to display images with a much greater dynamic range than the basic Rec-709 or Rec-2020 standards allow. There is in fact a new standard called Rec-2100 specifically for HDR television. Rec-2100 uses the same colorspace as Rec-2020 but then pairs that bigger colorspace with either Hybrid Log Gamma or ST2084 gamma, also know as PQ (Perceptual Quantiser). As the FS7 II does not have PQ or HLG as gamma curves you cannot shoot material that is directly compatible with Rec-2100. But what you can do is shoot using S-Log2/S-Log3 with S-Gamut/S-Gamut3/SGamut3.cine which will give you the sensors full colorspace with the sensors full 14 stop dynamic range. Then in post production you can grade this to produce material that is compatible with the Rec-2100 standard or the Rec-2020 standard. But of course you can do this with an original FS7 (or F5) too.
So, when would you actually use the FS7 II’s Rec-2020 colorspace rather than S-Log/S-Gamut?
First of all you don’t want to use it unless you are producing content to be shown on Rec-2020 displays. Recording using Rec-2020 color gamut and then showing the footage on a Rec-709 display will result in washed out colors that don’t look right.
You would probably only ever use it if you were going to output directly from the camera to a monitor that only supports Rec-2020 color or for a project that will be specifically shown on a standard dynamic range Rec-2020 display. So, IMHO this extra colorspace is of very limited benefit. For most productions regular Rec-709 or S-Log/S-Gamut will still be the way forward unless Sony add Hybrid Log Gamma or PQ gamma to the camera as well. Adding HLG or PQ however has problems of it’s own as the existing viewfinders can only show standard dynamic range images, so an external HDR capable monitor would be needed.
Rec-2020 recording gamut is a nice thing to have and for some users it may be important. But overall it’s not going to be a deal breaker if you only have a standard FS7 as the S-Log workflow will allow you to produce Rec-2020 compatible material.
In case you missed the webinars I presented yesterday here are recordings of the 2 afternoon sessions. The first one on HDR, what is it and what does it mean for you. The second is a question and answers session on Sony’s large sensor cameras, from the FS5 to the F55. There were quite a few a6300 and A7s questions thrown in there too!
Hopefully I will be able to find a sponsor that will be able to make these a regular event.
4K is cool, higher resolution, sharper pictures, but sometimes it’s tough to tell the difference between good HD and 4K, especially on a small screen. But HDR….. well HDR really does have that wow factor. Finally we will be able to see images on the screen that have contrast and brightness that is true to life. Vibrant, vivid high resolution images, no more muddy low contrast, dull images.
First of all, lets get this straight, this is not the same thing as the HDR photography that’s been around for an age where you take multiple images at different exposures to capture a massive dynamic range that you then process with photoshop or similar to create some kind of artistic but otherwise un-natural looking picture with un real contrast. Video HDR (or at least what’s being talk about now) is about displaying images on screens that have a dynamic range that closely matches the real world.
And you know what the best bit of this is? A lot of us already have cameras that are shooting HDR or that can be made at least partially HDR capable at no additional cost!
So what is HDR?
Historically television and cinema standards have been limited by display technology. Today a high quality LCD TV will only show a dynamic range of around 6 stops. If you have a light meter check it out. Measure the brightest whites and the deepest blacks and you should find a 5 to 6 stop range. Because cinema screens depend on reflecting light there are limits as to the contrast range that you will see in the cinema too. This has been the case since the very beginning of film making. Yet today we have cameras that can capture dynamic ranges well in excess of this, even an older camera such as a Sony EX1 can manage to record 11 stops, but with normal TV’s and monitors we have no way of showing this 11 stop (or more) range 1:1. So we massage the captured image to fit within the current conventional 6 stop display range using fancy things like the “knee” or special gamma curves like cinegamma, hypergamma or by grading and fine tuning the image in post production.
It’s all about the display.
The key technology that’s changing this is OLED displays. Remember dynamic range is not just about highlights but also about deep, dark shadows. We can make LCD screens brighter, much brighter. An LCD panel works by having a large light source behind an array of tiny electronically controlled ND filters. But these ND filters are never 100% dark, some light always leaks through. This means that when you make the back light brighter the blacks become less black as more light leaks through, so you don’t increase the contrast, only the brightness. The other issue is that current TV broadcasting standards (rec-709) are designed to work within the limitations of current display tech, so we don’t actually broadcast more than a 6 stop range. If we did the pictures wouldn’t look right on a 6 stop screen.
An OLED display on the other hand uses an array of individual LED emitters that are totally dark when they are off and can be very bright when all the way on. As a result they are capable of displaying a far greater dynamic range. TV and monitor manufacturers are now producing displays that are capable of showing dynamic ranges well in excess of the normal 6 stop range. If we then change the standard of the signals that we send to these displays to include a greater dynamic range that’s when the magic starts to happen. But it’s not just about contrast, it’s also about color. OLED displays can also show much more highly saturated colors.
You have to see it to believe it.
Unfortunately there is no way I can show you HDR here. Your computer monitor probably only has a 6 stop range. So to really see and appreciate HDR you are going to have to go and see a demo. There will be many at IBC. Imagine a picture of a sunset where the clouds and sky really are VIVID orange, an orange that positively glows from the screen illuminating the faces of the viewers. Meanwhile in the same shot there is a deep dark canyon in the foreground and you can see every detail in the deepest shadows of that canyon. Or how about a night time cityscape where the unlit buildings are dark but still clear to see, meanwhile the lights on the buildings are like tiny bright diamonds of brilliant light. Maybe the easiest to imagine is a shot across water where the ripples of the water catching the sun really, really do sparkle and catch your eye. But remember it’s not just about a brighter display, but ones with much, much greater contrast and much richer colors.
Are there limits to HDR? Well yes there are, but these limits are becoming more to do with what is comfortable to view rather than what the display technology can do. Sony’s X300 HDR monitor can show I believe around an 11 stop range. Some colorists have told me that working on HDR material in a dark grading suite for a few hours can be quite tiring due to the increased eyestrain. Let’s face it, we wouldn’t want a shot of the setting sun that is so bright that it makes your eye’s hurt. So in practice I think 10 to 11 stops is about the natural limit of what we will be comfortable watching on a screen at home. But this is an enormous 10 fold increase over what we have now.
It’s FREE! Well, at least shooting and distribution is.
One key thing about HDR is that it doesn’t need any more bandwidth to broadcast or distribute than any other image of the same size. All you need to do is change the gamma curve and color space used. This means that OTT (Over The Top – web and internet) delivery services such as Netflix or Amazon can stream in HDR without needing to make any changes to their infrastructure, all they need to do is grade the programme to suit an HDR display. Right now you can already find a number of movies to stream in HDR and many, many more programmes will be available from Netflix and Amazon Prime in HDR this year.
The next thing to consider is that if you have been shooting material with a camera dynamic range greater than 10 or 11 stops then you may already have content that is going to look great in HDR. S-Log material is perfect for HDR, material shot by the F55 using S-Gamut or S-Gamut3 is excellent for HDR as not only does it have a high dynamic range but it’s sensor also has a wide color gamut that will capture those highly saturated vibrant colors that only an HDR display can show. The F5 and FS7 will also shoot great material ready for HDR, although without some of the extended color range that the F55 is capable of. Even material shot with a Cinegamma or Hypergamma can be graded for HDR and in most cases will look better in HDR than it does on a conventional display.
So for us shooters, many of us already have equipment that can produce HDR content, in fact HDR will be the first time many of us will actually truly be able to see what we are shooting! To grade and produce HDR content you are going to need to invest in an HDR display. I’d love to get one of the new HDR capable Sony BVM-X300 monitors, but at £25k it’s too steep for me, so I will have to wait for a good quality HDR TV. The biggest issue with HDR will be that you will need to produce a different grade for HDR distribution compared to conventional Rec-709 distribution. But it must be remembered that many high end productions will already have different grades depending on the distribution method. After all a DVD or Bluray Rec-709 release of a film will need a different grade to the DCI-P3 cinema release.
Like 4K, HDR is already here. It’s not mainstream just yet, but it really isn’t far away. This isn’t a technology for the future, it’s a technology for today. Give it another 18 months and HDR TV’s will be common place in most TV stores, just as 4K TV’s are readily available now. Movie studios are sitting on huge archives of films that with a re-grade will look amazing in HDR. With the new 4K Bluray standard able to carry HDR content we really are looking at a tangible revolution in the quality of home viewing. Not just higher resolution but also higher contrast and dynamic range. If you are starting a big project now or want your material to have a long shelf life, you really should be shooting in 4K and using log or raw right now.
Better at home than in the cinema?
It’s interesting to consider that HDR is something that’s going to work much better in the home or at least via a display panel rather than via projection, so the home viewing experience may well exceed the cinema viewing experience (assuming that you have decent sized screen and good sound system). The next generation broadcasting standard Rec-2020 allows for HDR. These are exciting times times and in the coming weeks I’m hoping to spend some time over at Sony’s Digital Motion Picture Center at Pinewood to learn more about grading and producing content for HDR, the details of which I’ll share with you here.
Bureaucracy in the way in Europe 🙁
In Europe we may have a problem. For HDR to work TV’s need to be brighter. Brighter TV’s consume more energy. At the moment it’s hard to sell an HDR TV in Europe as most exceed the power consumption limits laid down by the EU for televisions which are based on typical LCD technology 🙁 So you may need to personally import an HDR TV from elsewhere.
Camera setup, reviews, tutorials and information for pro camcorder users from Alister Chapman.