Researchers at the Singapore-MIT Alliance for Research and Technology (SMART) have developed a new silicon Light Emitting Diode (LED) and holographic microscope which between them could help turn your smartphone into a powerful, high-resolution microscope. Together they are both the world’s smallest LED and the world’s smallest holographic microscope. This LED, they say, is comparable […]
Dr. Anna Lembke, a top expert in addiction medicine, talks about the Plenty Paradox and the struggles of balancing access and addiction in a world of plenty. She explains how addiction works in the brain and how technology affects it, and gives tips for having healthy relationships with digital devices. Dr. Lembke teaches psychiatry at Stanford University School of Medicine and is the head of the Stanford Addiction Medicine Dual Diagnosis Clinic. Some topics we discuss: Effects of technology on addiction, including increased pleasure-seeking and the importance of balance. Science of addiction, including pleasure-inducing chemicals and effects of drug use on the brain. Changes in addiction due to technology, such as digital drugs, and social media’s impact on mental health. Practical tips for healthy relationships with devices, such as setting limits and using technology intentionally. Impact of addiction on attention and well-being, including compulsive behaviors and self-care. Positive solutions for addressing addiction, such as education, taxation, and legal regulations. Enjoy! FOLLOW DR. LEMBKE : Dopamine Nation | website Listen to the Podcast Subscribe
Well, I was recently asked if I could come up with a rig to do the same using Sony cameras for an upcoming blockbuster feature with an A-list director being shot by a top DP. This kind of challenge is something I enjoy immensely, so how could I not accept the challenge! I had some insight into how Hoyte Van Hoytema did it but I had none of the fine details and often its the fine details that make all the difference. And this was no exception. I discovered many small things that need to be just right if this process is to work well. There are a lot of things that can trip you up badly.
So a frantic couple of weeks ensued as I tried to learn everything I could about infrared photography and video and how it could be used to improve traditional day for night shooting. I don’t claim any originality in the process, but there is a lot of information missing about how it was actually done in Nope. I have shot with infrared before, so it wasn’t all new, but I had never used it this way before.
As I did a lot of 3D work when 3D was really big around 15 years ago, including designing award winning 3D rigs, I knew how to combine two cameras on the same optical axis. Even better I still had a suitable 3D rig, so at least that part of the equation was going to be easy (or at least that’s what I thought).
Building a “Test Mule”.
The next challenge was to create a low cost “test mule” camera before even considering what adaptations might be needed for a full blown digital cinema camera. To start with this needed to be cheap, but it also needed to be full frame and capable of taking a wide range of cinema lenses and sensitive to both visible and infrared light. So, I took an old A7S that had been gathering dust for a while, dismantled it and removed the infrared filter from the sensor.
A7S being modified for infrared (full spectrum).Panavised and Infrared sensitive A7S with Panavision Primo lens.
As the DP wanted to test the process with Panavision lenses the camera was fitted with a PV70 mount and then collimated in it’s now heavily modified state (collimation has some interesting challenges when working with the very different wavelength of infrared light compared to visible). Now I could start to experiment, pairing the now infrared sensitive A7S with a second camera on the 3D rig. We soon found issues with this setup, but it allowed me to take the testing to the next stage before committing to modifying a more expensive camera for infrared.
This testing was needed to determine exactly what range of infrared light would produce the best results. The range of infrared you use is determined by filters added to the camera to cut the visible light and only pass certain parts of the infrared spectrum. There are many options, different filters work in slightly different ways. And not only do you need to test the infrared filters but you also need to consider how different neutral density filters might behave if you need to reduce the IR and visible light. Once I narrowed down the range of filters I wanted to test the next challenge was find very high quality filters that could either be fitted inside the camera body behind the lens or that were big enough (120mm +) for the Panavision lenses that were being considered for the film.
Once I had some filters to play with the next step was to start test shooting. I cheated here a bit, for some of the initial testing I used a pair of zoom lenses as was pairing the A7S with several different cameras for the visible spectrum. The scan areas of the different sensors of the A7S and the visible light cameras were typically very slightly different sizes. So, a zoom was used to provide the same field of view from both cameras so that both could be more easily optically aligned on the 3D rig. You can get away with this, but it makes more work for post production as the distortions in each lens will be different and need correcting. For the film we realised we would need identical scan sizes and matched lenses, but that could come later once we knew how much camera modification would be needed.
At this point I shot around 100 different filter and exposure tests that I then started to compare in post production. When you get it all just right the sky in the infrared image becomes very dark, almost black and highlights become very “peaky”. If you use the luminance from the infrared camera with its black sky and peaky highlights and then add in a bit of colour and textural detail from the visible camera it can create a pretty convincing day for night look. Because you have a near normal visible light exposure you can fine tune the mix of infrared and visible in post production to alter the brightness and colour of the final composite shot giving you a wide range of control.
So – now I know how to do it, the next step was to take it from the test bed to a pair of matching cinema quality cameras and lenses for a full scale test shoot. When you have two camera on a 3D rig the whole setup can get very heavy, very fast Therefore the obvious camera to adapt was a Sony Venice 2 with the 8K sensor as this can be made very compact by using the Rialto unit to split the sensor from the camera body – In fact one of the very first uses of Rialto was for 3D shooting on Avatar – The Way of Water.
With a bit of help from Panavision we adapted a Panavised Venice 2, making it full spectrum and then adding a carefully picked (based on my testing) special infrared filter into the cameras optical path. This camera was configured using a Rialto housing to keep it compact and light so that when placed on the 3D rig with the visible light Venice the weight remained manageable. The lenses used were Panavision PV70 Primo’s (if you want to use these lenses for infrared – speak to me first, there are some things you need to know).
3D rig with an Infrared capable Venice Rialto and normal Venice 2 with Panavision Primo lenses.
And then with the DP in attendance, with smoke and fog machines, lights and grip we tested. For the first few shot we had scattered clouds but soon the rain came and then it poured down for the rest of the day of tests. Probably the worst possible weather conditions for a day for night shoot. But that’s what we had and of course for the film itself there will be no guarantee of perfect weather.
Testing the complete day for night IR rig.
Testing how smoke behaves in infrared. Different types of smoke and haze and different types of lights behave very differently in infrared.
The large scale tests gave us an opportunity to test things like how different types of smoke and haze behave in infrared and also to take a look at interactions with different types of light sources. With the right lights you can do some very interesting things when you are capturing both visible light and infrared opening up a whole new world of possibilities for creating unique looks in camera.
From there the footage went to the production companies post production facilities to produce dailies for the DP to view before being presented to the studios post production people. Once they understood the process and were happy with it there was a screening for the director along with a number of other tests for lighting and lenses.
Along the way I have learnt an immense amount about this process and how it works. What filters to use and when, how to adapt different cameras, how different lenses behave in the infrared spectrum (not all lenses can be used). Collimating adapted cameras for infrared is interesting as many of the usual test rigs will produce misleading or confusing results. I’ve also identified several other ways that a dual camera setup can be used to enhance shooing night scenes, both day for night and as well as at night, especially for effects heavy projects.
At the time of writing it looks like most of the night scenes in this film will be shot at night, they have the budget and time to do this. But the director and DP have indicated that there are some scenes where they do wish to use the process (or a variation of it), but they are still figuring out some other details that will affect that decision.
Whether it gets used for this film or not I am now developing a purpose designed rig for day for night with infrared as I believe it will become a popular way to shoot night scenes. My cameras of choice for this will be a pair of Venice cameras. But other cameras can be used provided one can be adapted for IR and both can be synchronised together. If you need a rig for day for night and someone that knows exactly how to do it, do get in touch!
I’m afraid I can’t show you the test results, that content is private and belongs to the production. The 3D rig is being modified as you don’t need the ability to shoot with the cameras optically separated, removing the moving parts will make the rig more stable and easier to calibrate. Plus a new type of beam splitter mirror with better infrared transmission properties is on the way. As soon as I get an opportunity to shoot a new batch of test content. I will share it here.
1985 was an interesting year in the life of corporate video, we got a new camera a Sony DXC-M3P. The Sony DXC-M3P is a professional analog video camera that was released in the 1980s. It features a 3-tube imaging system, which provides high-quality color reproduction and low-light sensitivity. The camera is designed for studio and
I’m feeling obsolete lately. Why? Let me tell you. Technology moves fast. So fast. Writing for Photofocus has allowed me to see just how quickly the photography industry — and the photography gear that come with it — has changed in the last six years. New photography gear It feels like all photographers ever want […]
Sony’s Cinema Line cameras all have the ability to record metadata from inertia and gyroscope sensors about the way the camera moves while shooting. This metadata can then be used to stabilise your footage in post production. The stabilisation that this can provide is normally very good and tends to look a lot more natural than using post production stabilisation that looks at the footage and tries to hold it steady. However, until recently the only way to make use of this metadata was via Sony’s Catalyst Browse software.
Now however an Open Source project known as GyroFlow has made it possible to use the Sony metadata in FCPX and DaVinci Resolve via an OpenFX plugin and a FCP-X plug-in. In addition there is a standalone GyroFlow application that can stabilise the footage and then export a stabilised version of the clip.
GyroFlow is a collaborative Open Source project, so different developers are working on different aspects and plug-ins, so it is a bit more disjointed than a lot of commercial products. But, it is free and it will get better, so why not give it a try. The main website for the project is here: http://gyroflow.xyz/
The XAVC family of codecs was introduced by Sony back in 2014. Until recently all flavours of XAVC were based on H264 compression. More recently new XAVC-HS versions were introduced that use H265. The most commonly used versions of XAVC are the XAVC-I and XAVC-L codecs. These have both been around for a while now and are well tried and well tested.
XAVC-I
XAVC-I is a very good Intra frame codec where each frame is individually encoded. It’s being used for Netflix shows, it has been used for broadcast TV for many years and there are thousands and thousands of hours of great content that has been shot with XAVC-I without any issues. Most of the in flight shots in Top Gun Mavericks were shot using XAVC-I. It is unusual to find visible artefacts in XAVC-I unless you make a lot of effort to find them. But it is a high compression codec so it will never be entirely artefact free. The video below compares XAVC-I with ProResHQ and as you can see there is very little difference between the two, even after several encoding passes.
XAVC-L
XAVC-L is a long GOP version of XAVC-I. Long GoP (Group of Pictures) codecs fully encode a start frame and then for the next group of frames (typically 12 or more frames) only store any differences between this start frame and then the next full frame at the start of the next group. They record the changes between frames using things motion prediction and motion vectors that rather than recording new pixels, moves existing pixels from the first fully encoded frame through the subsequent frames if there is movement in the shot. Do note that on the F5/F55, the FS5, FS7, FX6 and FX9 that in UHD or 4K XAVC-L is 8 bit (while XAVC-I is 10 bit).
Performance and Efficiency.
Long GoP codecs can be very efficient when there is little motion in the footage. It is generally considered that H264 long GoP is around 2.5x more efficient than the I frame version. And this is why the bit rate of XAVC-I is around 2.5x higher than XAVC-L, so that for most types of shots both will perform similarly. If there is very little motion and the bulk of the scene being shot is largely static, then there will be situations where XAVC-L can perform better than XAVC-I.
Motion Artefacts.
BUT as soon as you add a lot of motion or a lot of extra noise (which looks like motion to a long GoP codec) Long GoP codecs struggle as they don’t typically have sufficiently high bit rates to deal with complex motion without some loss of image quality. Let’s face it, the primary reason behind the use of Long GoP encoding is to save space. And that’s done by decreasing the bit rate. So generally long GoP codecs have much lower bit rates so that they will actually provide those space savings. But that introduces challenges for the codec. Shots such as cars moving to the left while the camera pans right are difficult for a long GoP codec to process as almost everything is different from frame to frame including entirely new background information hidden behind the cars in one frame that becomes visible in the next. Wobbly handheld footage, crowds of moving people, fields of crops blowing in the wind, rippling water, flocks of birds are all very challenging and will often exhibit visible artefacts in a lower bit rate long GoP codec that you won’t ever get in the higher bit rate I frame version.
Concatenation.
A further issue is concatenation. The artefacts that occur in long GoP codecs often move in the opposite direction to the object that’s actually moving in the shot. So, when you have to re-encode the footage at the end of an edit or for distribution the complexity of the motion in the footage increases and each successive encode will be progressively worse than the one before. This is a very big concern for broadcasters or anyone where there may be multiple compression passes using long GoP codecs such as H264 or H265.
Quality depends on the motion.
So, when things are just right and the scene suits XAVC-L it will perform well and it might show marginally fewer artefacts than XAVC-I, but those artefacts that do exists in XAVC-I are going to be pretty much invisible in the majority of normal situations. But when there is complex motion XAVC-L can produce visible artefacts. And it is this uncertainty that is a big issue for many as you cannot easily predict when XAVC-L might struggle. Meanwhile XAVC-I will always be consistently good. Use XAVC-I and you never need to worry about motion or motion artefacts, your footage will be consistently good no matter what you shoot.
Broadcasters and organisations such as Netflix spend a lot of time and money testing codecs to make sure they meet the standards they need. XAVC-I is almost universally accepted as a main acquisition codec while XAVC-L is much less widely accepted. You can use XAVC-L if you wish, it can be beneficial if you do need to save card or disk space. But be aware of its limitations and avoid it if you are shooting handheld, shooting anything with lots of motion, especially water, blowing leaves, crowds etc. Also be aware that on the F5/F55, the FS5, FS7, FX6 and FX9 that in UHD or 4K XAVC-L is 8 bit while XAVC-I is 10 bit. That alone would be a good reason NOT to choose XAVC-L.
Canon has announced that they’ve developed a 19-megapixel global shutter full-frame CMOS sensor. There are four different models of the same LI5030S sensor in colour, black and white, colour/near-infrared and full spectrum, all capable of shooting full resolution at up to 58 frames per second. Canon says that the new sensor will be ready to […]
Smartphones have gotten to the level of quality they are at not just because the sensor hardware is improving, but also because software and processing has gotten a whole lot better. So why aren’t camera makers taking advantage of this technology?
