Category Archives: Technology

SDI Failures and what YOU can do to stop it happening to you.

Sadly this is not an uncommon problem. Suddenly and seemingly for no apparent reason the SDI output on your camera stops working. And this isn’t a new problem either, SDI ports have been failing ever since they were first introduced. This issue affect all types of SDI ports. But it is more likely with higher speed SDI ports such as 6G or 12G as they operate at higher frequencies and as a result the components used are more easily damaged as it is harder to protect them without degrading the high frequency performance.

Probably the most common cause of an SDI port failure is the use of the now near ubiquitous D-Tap cable to power accessories connected to the camera. The D-Tap connector is sadly shockingly crudely designed. Not only is it possible to plug in many of the cheaper ones the wrong way around but with a standard D-Tap plug there is no mechanism to ensure that the negative or “ground” connection of the D-Tap cable makes or breaks before the live connection. There is a however a special but much more expensive D-Tap connector available that includes electronic protection against this very issue – see: https://lentequip.com/products/safetap

Imagine for a moment you are using a monitor that’s connected to your cameras SDI port. You are powering the monitor via the D-Tap on the cameras battery as you always do and everything is working just fine. Then the battery has to be changed. To change the battery you have to unplug the D-Tap cable and as you pull the D-Tap out, the ground connection disconnects fractionally before the live connection. During that moment there is still positive power going to the monitor but because the ground on the D-Tap is now disconnected the only ground route back to the battery becomes via the SDI cable through the camera. For a fraction of a second the SDI cable becomes the power cable and that power surge blows the SDI driver chip.

After you have completed the battery swap, you turn everything back on and at first all appears good, but now you can’t get the SDI output to work. There’s no smoke, no burning smells, no obvious damage as it all happened in a tiny fraction of a second. The only symptom is a dead SDI.

And it’s not only D-Tap cables that can cause problems. A lot of the cheap DC barrel connectors have a center positive terminal that can connect before the outer barrel makes a good connection. There are many connectors where the positive can make before the negative.

It can also happen when powering the camera and monitor (or other SDI connected devices like a video transmitter) via separate mains adapters. The power outputs of most of the small, modern, generally plastic bodied switch mode type power adapters and chargers are not connected to ground. They have a positive and negative terminal that “floats” above ground at some unknown voltage. Each power supplies negative rail may be at a completely different voltage compared to ground.  So again an SDI cable connected between two devices, powered by different power supplies will act as the ground between them and power may briefly flow down the SDI cable as the SDI cables ground brings both power supply negative rails to the same common voltage. Failures this way are less common, but do still occur. 

For these reasons you should always connect all your power supplies, power cables and especially D-Tap or other DC power cables first. Then while everything remains switched off connect the SDI cables. Only when everything is connected should you turn anything on. If unplugging or re-plugging a monitor (or anything else for that matter) turn everything off first. Do not connect or disconnect anything while any of the equipment is on.  Although to be honest the greatest risk is at the time you connect or disconnect any power cables such as when swapping a battery where you are using the D-Tap to power any accessories. So if changing batteries, switch EVERYTHING off first, then disconnect your SDI cables before disconnecting the D-Tap or other power cables next.

(NOTE: It’s been brought to my attention that Red recommend that after connecting the power, but before connecting any SDI cables you should turn on any monitors etc. If the monitor comes on OK, this is evidence that the power is correctly connected. There is certainly some merit to this. However this only indicates that there is some power to the monitor, it does not ensure that the ground connection is 100% OK or that the ground voltages at the camera and monitor are the same. By all means power the monitor up to check it has power, then I still recommend that you turn it off again before connecting the SDI).
 
The reason Arri talk about shielded power cables is because most shielded power cables use connectors such as Lemo or Hirose where the body of the connector is grounded to the cable shield. This helps ensure that when plugging the power cable in it is the ground connection that is made first and the power connection after. Then when unplugging the power breaks first and ground after. When using properly constructed shielded power cables with Lemo or Hirose connectors it is much less likely that these issues will occur (but not impossible).

Is this an SD fault? No, not really. The fault lies in the choice of power cables that allow the power to make before the ground or the ground to break before the power breaks.  Or the fault is with power supplies that have poor or no ground connection. Additionally you can put it down to user error. I know I’m guilty of rushing to change a battery and pulling a D-Tap connector without first disconnecting the SDI on many occasions, but so far I’ve mostly gotten away with it (I have blown an SDI on one of my Convergent Design Odysseys).

If you are working with an assistant or as part of a larger crew do make sure that everyone on set knows not to plug or unplug power cables or SDI cables without checking that it’s OK to do so. How many of us have set up a camera, powered it up, got a picture in the viewfinder and then plugged an SDI cable between the camera and a monitor that doesn’t have a power connection yet or already on and plugged in to some other power supply? Don’t do it! Plug and unplug in the right order – ALL power cables and power supplies first, check power is going to the camera, check power is going to the monitor, then turn it all off first, finally plug in the SDI.

Accsoon CineEye 2S

accsoon_cineeye2s_cineeye_2_5g_wireless_1611053137_1617027 Accsoon CineEye 2SWireless video transmitters are nothing new and there are lots of different units on the market. But the Accsoon CineEye 2S stands out from the crowd for a number of reasons.

First is the price, at only £220/$300 USD it’s very affordable for a SDI/HDMI wireless transmitter. But one thing to understand is that it is just a transmitter, there is no reciever. Instead you use a phone or tablet to receive the signal and act as your monitor. You can connect up to 4 devices at the same time and the latency is very low.  Given that you can buy a reasonably decent Android tablet or used iPad for £100/$140 these days, it still makes an affordable and neat solution without the need to worry about cables, batteries or cages at the receive end. And most people have an iPhone or Android phone anyway. The Accsoon app includes waveform and histogram display, LUT’s, peaking and all the usual functions you would find on most pro monitors. So it saves tying up an expensive monitor just for a directors preview. You can also record on the tablet/phone giving the ability for the director or anyone else linked to it to independently play back takes as he/she wishes while you use the camera for other things.

1611053189_IMG_1474630 Accsoon CineEye 2S

Next is the fact that it doesn’t have any fans. So there is no additional noise to worry about when using it. It’s completely silent. Some other units can get quite noisy.

And the best bit: If you are using an iPhone or iPad with a mobile data connection the app can stream your feed to YouTube, Facebook or any similar RMTP service. With Covid still preventing travel for many this is a great solution for an extremely portable streaming solution for remote production previews etc. The quality of the stream is great (subject to your data connection) and you don’t need any additional dongles or adapters, it just works! 

Watch the video, which was streamed live to YouTube with the CineEye 2S  for more information. At 09.12 I comment that it uses 5G – What I mean is that it has 5Ghz WiFi as well as 2.5Ghz Wifi for the connection between the CineEye and the phone or tablet. 5Ghz WiFi is preferred where possible for better quality connections and better range. https://accsoonusa.com/cineeye/

 

Checking SD Cards Before First Use.

sd-card-copy Checking SD Cards Before First Use.With the new FX6 making use of SD cards to record higher bit rate codecs the number of gigabytes of SD card media that many user will will be getting through is going to be pretty high. The more gigabytes of memory that you use, the more the chance of coming across a duff memory cell somewhere on your media.

Normally solid state media will avoid using any defective memory areas. As a card ages and is used more, more cells will become defective and the card will identify these and it should avoid them next time. This is all normal, until eventually the memory cell failure rate gets too high and the card becomes unusable – typically after hundreds or even thousands of cycles.

However – the card needs to discover where any less than perfect  memory cells are and there is a chance that some of the these duff cells could remain undiscovered in a card that’s never been completely filled before. I very much doubt that every SD card sold is tested to its full capacity, the vast volume of cards made and time involved makes this unlikely.

For this reason I recommend that you consider testing any new SD cards using software such as H2Testw for windows machines or SDSpeed for Mac’s. However be warned to fully test a large card can take a very, very long time.

As an alternative you could simply place the card in the camera and record on it until its full. Use the highest frame rate and largest codec the card will support to fill the card as quickly as possible. I would break the recording up into a few chunks. Once the recording has finished check for corruption by playing the clips back using Catalyst Browse or your chosen edit software.

This may seem like a lot of extra work, but I think it’s worth it for piece of mind before you use your new media on an important job.

Atomos Adds Raw Over SDI For The Ninja V via the AtomX.

I know this is something A LOT of people have been asking for. For a long time it has always seemed odd that only the Shogun 7 was capable of recording raw from the FX9 and then the FX6 while the the little Ninja V could record almost exactly the same raw form the A7SIII.

Well the engineers at Atomos have finally figured out how to pass raw via the AtomX SDI adapter to the Ninja V. The big benefit of course being the compact size of the Ninja V.

There are a couple of ways of getting the kit you need to do this.

If you already have a Ninja V (they are GREAT little monitor recorders, I’ve taken mine all over the world, from the arctic to Arabian deserts) you simply need to buy an AtomX SDI adapter and once you have that buy a raw licence from the Atomos website for $99.00.

If you don’t have the Ninja V then you can buy a bundle called the “Pro Kit” that includes everything you need including a Ninja V with the raw licence pre-installed, The AtomX SDI adapter, a D-Tap power adapter cable, a mains power supply and a sun hood. The cost of this kit will be around $950 USD or £850 GBP + tax, which is a great price.

On top of that you will need to buy suitable fast SSD’s.

Like the Shogun 7 the Ninja V can’t record the 16 bit raw from the FX6 or FX9 directly, so Atomos take the 16 bit linear raw and convert it using a visually lossless process to 12 bit log raw. 12 bit log raw is a really nice raw format and the ProResRaw codec helps keep the files sizes nice and manageable.

This is a really great solution for recording raw from the FX6 and FX9. Plus if you already have an A7SIII you can use the Ninja V to record via HDMI from that too.

Here’s the press release from Atomos:

c6c43288-9b4b-4ac7-8889-16c01dbb6300 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.
f8cd773f-872b-4e63-a7f3-a53142662664 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.
The Atomos Ninja V Pro Kit is here to equip you with increased
professional I/O, functionality and accessories.

The Ninja V Pro Kit has been designed to bridge the gap between compact cinema and mirrorless cameras that can output RAW via HDMI or SDI. Pro Kit also pushes these cameras’ limits, recording up to 12-bit RAW externally on the Ninja’s onboard SSD. Additionally, Pro Kit provides the ability to cross covert signals providing a versatile solution for monitoring, play out and review.
 
7ae96b67-7f27-4f54-b637-5bed0cb685d5 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.
What comes in the Pro Kit?
  • Ninja V Monitor-Recorder with pre-activated RAW over SDI
  • AtomX SDI Module
  • Locking DC to D-Tap cable to power from camera battery
  • AtomX 5″ Sunhood
  • DC/Mains power with international adaptor kit
Ninja V Pro Kit offers a monitor and recording package to cover a wide range of workflows.
097d35da-ecfb-4acd-a43f-45a0098e9907 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.

Why choose Ninja V Pro Kit?
  • More powerful and versatile I/O for Ninja V – Expand your Ninja V’s capability with the Pro Kit with the ability to provide recordings in edit-ready codecs or as proxy files from RED or ARRI cameras.
  • Accurate and reliable daylight viewable HDR or SDR – To ensure image integrity, the AtomX 5″ Sunhood is included and increases perceived brightness under challenging conditions or can be used to dial out ambient light to increase the view in HDR
  • HDMI-to-SDI cross conversion – HDMI or SDI connections can be cross converted, 4K to HD down converts RAW to video signals to connect to other systems without the need for additional converters.
  • Record ProRes RAW via SDI to selected cameras*:
a9004691-3a6a-43eb-a2e3-bcced1e9fb74 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.
  • Three ways to power your Ninja:
    – DC power supply – perfect for in the studio.
    – DTap cable – perfect for on-set, meaning your rig can run from a single power source.
    – Optional NPF battery or any four-cell NPF you might have in your kit bag. 
c3522982-3d97-464b-976f-50cdf918f2b9 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.

The ProRes RAW Advantage
ProRes RAW is now firmly established as the new standard for RAW video capture, with an ever-growing number of supported HDMI and SDI cameras. ProRes RAW combines the visual and workflow benefits of RAW video with the incredible real-time performance of ProRes. The format gives filmmakers enormous latitude when adjusting the look of their images and extending brightness and shadow detail, making it ideal for HDR workflows. Both ProRes RAW and the higher bandwidth, less compressed ProRes RAW HQ are supported. Manageable file sizes speed up and simplify file transfer, media management, and archiving. ProRes RAW is fully supported in Final Cut Pro, Adobe Premiere Pro, Avid Media Composer 2020.10 update, along with a collection of other apps including ASSIMILATE SCRATCH, Colorfront, FilmLight Baselight, and Grass Valley Edius.
 
38031027-d6e9-4d58-b3aa-8672ead94c51 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.

Existing Ninja V and AtomX SDI module owners
While the Pro Kit offers a complete bundle, existing Ninja V owners can enhance their equipment to the same level by purchasing the AtomX SDI module for $199, and the New RAW over SDI and HDMI RAW to SDI video feature can also be added to the Ninja V via separate activation key from the Atomos website for $99. 

Existing AtomX SDI module owners will receive the SDI < > HDMI cross conversion for 422 video inputs in the 10.61 firmware update for Ninja V update. You will also be able to benefit from RAW over SDI recording with the purchase of the SDI RAW activation key. This feature will be available from the Atomos website in February 2021.
 
ecd0a301-71e2-42ac-877a-74b52bea63a0 Atomos Adds Raw Over SDI For The Ninja V via the AtomX.
 
Special Offer for Pro Kit buyers
The first batch of Ninja V Pro Kits will include a FREE Atomos CONNECT in the box.
Connect allows you to start streaming at up to 1080p60 directly from your Ninja V!
Learn more about Connect here.
 

Availability
The Ninja V Pro Kit is available to purchase from your local reseller.
Find your local reseller here.

$949 USD
EX LOCAL TAXES

*Selected cameras only – RAW outputs from Sony’s FS range (FS700, FS5, FS7) are NOT supported on Ninja V with AtomX SDI Module and RAW Upgrade. Support for these cameras is ONLY available on Shogun 7.

Accsoon Cineeye 2S Wireless Video Link with Streaming Function

So there are now quite a lot of these devices appearing on the market. I have a Hollyland Mars 400 kit and it works really well. But this one caught my eye because it includes the ability to stream to platforms such as YouTube using RTMP.
In these days of remote production being able to stream the cameras output to a remote client or producer could prove very useful.

I haven’t seen one in person and I don’t know the company, so no idea if it’s actually any good. But certainly on paper it’s really interesting. 

Here’s the info from the press release. 

 

4ea1d055e1c53d66df52fadef6c585cb Accsoon Cineeye 2S Wireless Video Link with Streaming Function

large-5670a05a205877021e33f12e53136126 Accsoon Cineeye 2S Wireless Video Link with Streaming Function
large-bc2872a444bb846886da7a79105e751b Accsoon Cineeye 2S Wireless Video Link with Streaming Function
large-674a2318d09a629ce7735414fd29f239 Accsoon Cineeye 2S Wireless Video Link with Streaming Function
large-b79eeb88e786297bf5c9c62100b8634a Accsoon Cineeye 2S Wireless Video Link with Streaming Function
large-66691526b2488b48538670f1cdf55130 Accsoon Cineeye 2S Wireless Video Link with Streaming Function
large-135545da2f66ca2d3efed39c58997487 Accsoon Cineeye 2S Wireless Video Link with Streaming Function
large-88ec9a63243d7f6cf966b225b890d987 Accsoon Cineeye 2S Wireless Video Link with Streaming Function

Xperia Pro – Is this the phone all video professionals should Own?

Screenshot-2021-01-27-at-17.13.22-537x500 Xperia Pro - Is this the phone all video professionals should Own?
The Xperia Pro has an HDMI input and can be used as a 4K HDR monitor.

 

A dramatic headline perhaps, but once I start to look at what the Xperia Pro can do, I can’t help but say – I want one! The Xperia Pro is so much more than just a phone for making calls or watching YouTube videos.

The Xperia Pro shares many features of Sony’s flagship Xperia 1 II and adds an HDMI input.

HDMI IN. Yes, that’s right – it has a 4K/HD HDMI input. So you can plug your camera into it and use it as an HDMI monitor, plus its HDR so you have a small pocket sized HDMI monitor. When I travel (travel – hopefully that will happen again) to remote locations I often don’t take a monitor because of the extra bulk. But being able to use a phone as a monitor from time to time would be such a help. It supports HDR and Rec2020 and has pinch to zoom if you need to enlarge the image to check focus etc.

Streaming from the HDMI input.

Install a streaming app on the phone and you can use it to stream the HDMI feed from any connected camera direct to your favorite platforms. No need to use clumsy tethering, just plug in the HDMI and start your favorite app.

5G millimeter wave. Because the phone features 5G millimeter wave connectivity, where available you will have access to extremely fast data transfer speeds for streaming or ftp transfers. The phone also includes a Network Visualiser App that allows you to find the best network connectivity so you can be sure of the best possible connection wherever you are.

3x High Quality Cameras. The Xperia Pro has three 12mp cameras with Zeiss lenses that are the equivalent of 16mm f2.2, a particularly impressive 24mm f1.7 as well as a 70mm f2.4. The cameras have been co developed by engineers from the Alpha team and feature full manual control as well as raw stills. For video it can shoot at 4K HDR at 24, 30, 60 and 120fps with an optional wide screen 21:9 (2.370:1) aspect ratio mode that matches the 21:9 aspect ratio of the phone itself.

Screenshot-2021-01-27-at-17.14.51-600x369 Xperia Pro - Is this the phone all video professionals should Own?

But all of this goodness comes at a price. Currently its priced at $2499 USD which is a huge amount of money for a phone. The very similar  Xperia 1 II without the HDMI input can be found for less than half of that. But for someone that streams a lot, perhaps for TV news applications there is a lot to like. You could use the phone as your camera or use the phone to stream from a better camera, easily and simply. With 5G you can use it to upload finished packages quickly and easily. The cost of any high end phone plus an HDR 4K monitor would be close to that of the Xperia Pro, so while it is a lot of money it isn’t perhaps as outrageous as it first seems.

You can find more information here: https://www.sony.com/electronics/professional-smartphones/xperia-pro#product_details_default

 

Sony Launches Airpeak Drone – Designed to carry Alpha sized cameras.

slide_aid_01-600x338 Sony Launches Airpeak Drone - Designed to carry Alpha sized cameras.
Sony Airpeak Drone

 

Sony has launched an entirely new division called Airpeak. Airpeak have produced a large drone that can carry an Alpha sized camera. They claim that this is the smallest drone capable of carrying an Alpha sized camera. It’s unknown at this time whether the Airpeak division will purely focus on larger drones capable of carrying non integrated cameras or whether they will also produce smaller drones with integral cameras. It would certainly make sense to leverage Sony’s sensor expertise by creating dedicated cameras for drones and then drones to carry those cameras. 

The drone market is going to be a tough one to make inroads into. There are already a couple of very well regarded drone manufacturers making some great drones such as the DJI inspire or Mavic Pro. But most of these are small and cannot carry larger external cameras. However the cameras that these drones are equipped with can deliver very high quality images – and they continue to get better and better. The use of larger drones for video applications is more specialist, however globally it is a large market. Whether Sony can compete in the more specialist area of larger drones that carry heavier payloads is yet to be seen. I hope the succeed.

One thing I intend to do in the next few years as the Sun enters the more active phase of it’s 11 year solar cycle is to shoot the Aurora from a drone and a camera like the A7S III and a larger, stable drone would be perfect. But there is no indication of pricing yet and a drone of this size won’t be cheap. So unless I decide to do a lot more drone work than I do already, perhaps it will be better to hire someone with the right kit. But that’s not as much fun as doing it yourself!

For more information on Airpeak do take a look at their website. There is already some impressive footage of it being used to shoot a Vision-S car on a test track.

Sony Airpeak Website.

 

Raw Isn’t Magic. With the right tools Log does it too.

Raw can be a brilliant tool, I use it a lot. High quality raw is my preferred way of shooting. But it isn’t magic, it’s just a different type of recording codec.
 
All too often – and I’m as guilty as anyone – people talk about raw as “raw sensor data” a term that implies that raw really is something very different to a normal recording. In reality it’s really not that different. When shooting raw all that happens is that the video frames from the sensor are recorded before they are converted to a colour image. A raw frame is still a picture, it’s just that it’s a bitmap image made up of brightness values, each pixel represented by a single brightness code value rather than a colour image where each location in the image is represented by 3 values one for each of Red, Green and Blue or Luma, Cb and Cr.

As that raw frame is still nothing more than a normal bitmap all the cameras settings such as white balance, ISO etc are in fact baked in to the recording. Each pixel only has one single value and that value will have been determined by the way the camera is setup. Nothing you do in post production can change what was actually recorded. Most CMOS sensors are daylight balanced, so unless the camera adjusts the white balance prior to recording – which is what Sony normally do – your raw recording will be daylight balanced.

Modern cameras when shooting log or raw also record metadata that describes how the camera was set when the image was captured. 

So the recorded raw file already has a particular white balance and ISO. I know lots of people will be disappointed to hear this or simply refuse to believe this but that’s the truth about a raw bitmap image with a single code value for each pixel and that value is determined by the camera settings.

This can be adjusted later in post production, but the adjustment range is not unlimited and it is not the same as making an adjustment in the camera. Plus there can be consequences to the image quality if you make large adjustments. 

Log can be also adjusted extensively in post too. For decades feature films shot on film were scanned using 10 bit Cineon log (which is the log gamma curve S-Log3 is based on) and 10 bit log used for post production until 12 bit and then 16 bit linear intermediates came along like OpenEXR. So this should tell you that actually log can be graded very well and very extensively.

But then many people will tell you that you can’t grade log as well as raw. Often they will give photographers as an example where there is a huge difference between what you can do with a raw photo and a normal image. But we also have to remember this is typically comparing what you can do with a highly compressed 8 bit jpeg file and an often uncompressed 12 or 14 bit raw file. It’s not a fair comparison, of course you would expect the 14 bit file to be better.

The other argument often given is that it’s very hard to change the white balance of log in post, it doesn’t look right or it falls apart. Often these issues are nothing to do with the log recording but more to do with the tools being used.

When you work with raw in your editing or grading software you will almost always be using a dedicated raw tool or raw plugin designed for the flavour of raw you are using. As a result everything you do to the file is optimised for the exact flavour of raw you are dealing with. It shouldn’t come as a surprise to find that to get the best from log you should be using tools specifically designed for the type of log you are using. In the example below you can see how Sony’s Catalyst Browse can perfectly correctly change the white balance and exposure of S-log material with simple sliders just as effectively as most raw formats.
 
Screenshot-2020-11-27-at-17.14.07 Raw Isn't Magic. With the right tools Log does it too.
On the left is the original S-Log3 clip with the wrong white balance (3200K) and on the left is the corrected image. The only corrections made are via the Temperature slider and exposure slider.
 
Applying the normal linear or power law (709 is power law) corrections found in most edit software to Log won’t have the desired effect and basic edit software rarely has proper log controls. You need to use a proper grading package like Resolve and it’s dedicated log controls. Better still some form of colour managed workflow like ACES where your specific type of log is precisely converted on the fly to a special digital intermediate and the corrections are made to the intermediate file. There is no transcoding, you just tell ACES what the footage was was shot on and magic happens under the hood. Once you have done that you can change the white balance or ISO of log material in exactly the same way as raw. There is very, very little difference.
 
Screenshot-2020-11-27-at-17.29.27 Raw Isn't Magic. With the right tools Log does it too.
The same S-Log3 clip as in the above example, this time in DaVinci Resolve using ACES. The only corrections being made are via the Temp slider for the white balance change and the Log-Offset wheel which in ACES provides a precise exposure adjustment.
 
When people say you can’t push log, more often than not it isn’t a matter of can’t, it’s a case of can – but you need to use the right tools.
 
After-correction-450x253 Raw Isn't Magic. With the right tools Log does it too.
This is what log shot with completely the wrong white balance and slightly over exposed looks like after using nothing but the WB and ISO sliders in Catalyst Browse. I don’t believe raw would have looked any different.
 
Less compression or a greater bit depth are where the biggest differences between a log or raw recording come from, not so much from whether the data is log or raw.  Don’t forget raw is often recorded using log, which kind of makes the “you can’t grade log” argument a bit daft.
 
Camera manufactures and raw recorder manufacturers are perfectly happy to allow everyone to believe raw is magic and worse still, let people believe that ANY type of raw must be better than all other types of recordings. Read though any camera forum and you will see plenty of examples of “it’s raw so it must be better” or “I need raw because log isn’t as good” without any comprehension of what raw is and how in reality it’s the way the raw is compressed and the bit depth that really matters.

If we take ProRes Raw as an example: For a 4K 24/25fps file the bit rate is around 900Mb/s. For a conventional ProRes HQ file the bit rate is around 800Mb/s. So the file size difference between the two is not at all big.
 
But the ProRes Raw file only has to store around 1/3 as many data points as the component ProResHQ file. As a result, even though the ProRes Raw file often has a higher bit depth, which in itself usually means better a better quality recording, it is also much, much less compressed and as a result will have fewer artefacts. 

It’s the reduced compression and deeper bit depth possible with raw that can lead to higher quality recordings and as a result may bring some grading advantages compared to a normal ProRes or other compressed file. The best bit is there is no significant file size penalty. So you have the same amount of data, but you data should be of higher quality. So given that you won’t need more storage, which should you use? The higher bit depth less compressed file or the more compressed file?

But, not all raw files are the same. Some cameras feature highly compressed 10 bit raw, which frankly won’t be any better than most other 10 bit recordings as you are having to do all the complex math to create a colour image starting with just 10 bit. Most cameras do this internally at at least 12 bit. I believe raw needs to be at least 12 bit to be worth having.

If you could record uncompressed 12 bit RGB or 12 bit component log from these cameras that would likely be just as good and just as flexible as any raw recordings. But the files would be huge. It’s not that raw is magic, it’s just that raw is generally much less compressed and  depending on the camera may also have a greater bit depth. That’s where the benefits come from.

Raw Myths. You Can’t Change The white Balance Of the Camera Or ISO in Post.

It’s amazing how often people will tell you how easy it is to change the white balance or adjust the ISO of raw footage in post. But can you, is it really true and is it somehow different to changing the ISO or white balance of Log footage?

Let’s start with ISO. If ISO is sensitivity, or the equivalent of sensitivity how on earth can you change the sensitivity of the camera once you get into post production. The answer is you can’t.

But then we have to consider how ISO works on an electronic camera. You can’t change the sensor in a video camera so in reality you can’t change how sensitive an electronic camera is (I’m ignoring cameras with dual ISO for a moment). All you can do is adjust the gain or amplification applied to the signal from the sensor.  You can add gain in post production too. So, when you adjust the exposure or using the ISO slider for your raw footage in post all you are doing is adjusting how much gain you are adding. But you can do the same with log or any other gamma. 

One thing that makes a difference with raw is that the gain is applied in such a way that what you see looks like an actual sensitivity change no matter what gamma  you are transforming the raw to. This makes it a little easier to make changes to the final brightness in a pleasing way. But you can do exactly the same thing with log footage.  Anything you do in post must be altering the recorded file, it can never actually change what you captured.

Changing the white balance in post: White Balance is no different to ISO, you can’t change in post what the camera captured. All you can do is modify it through the addition or subtraction of gain.

Think about it. A sensor must have a certain response to light and the colours it sees depending on the material it’s made from and the colour filters used. There has to be a natural fixed white balance or a colour temperature that it works best at.

The Silicon that video sensors are made from is almost always more sensitive at the red end of the spectrum than the blue end. So as a result almost all sensors tend to produce the best results with light that has a lot of blue (to make up for the lack of blue sensitivity) and not too much red. So most cameras naturally perform best with daylight and as a result most sensors are considered daylight balanced.

If a camera produces a great image under daylight how can you possibly get a great image under tungsten light without adjusting something? Somehow you need to adjust the gain of the red and blue channels.

Do it in camera and what you record is optimised for your choice of colour temperature at the time of shooting. But you can always undo or change this in post by subtracting or adding to whatever was added in the camera.

If the camera does not move away from its native response then if you want anything other than the native response you will have to do it in post and you will be recording at the cameras native white balance. If you want a different colour temp then you need to add or subtract gain to the R & B channels in post to alter it.

Either way what you record has a nominal white balance and anything you do in post is skewing what you have recorded using gain. There is no such thing as a camera with no native white balance, all cameras will favour one particular colour temperature. So even if a manufacturer claims that the white balance isn’t baked in what they mean is they don’t offer the ability to make any adjustments to the recorded signal. If you want the very best image quality, the best method is to adjust at the time of recording. So, as a result a lot of camera manufacturers will skew the gain of the red and blue channels of the sensor in the camera when shooting raw as this optimises what you are recording. You can then skew it again in post should you want a different balance. 

With either method if you want to change the white balance from what was captured you are altering the gain of the red and blue channels. Raw doesn’t magically not have a white balance, so shooting with the wrong white balance and correcting it in post is not something you want to do. Often you can’t correct badly balanced raw any better than you can correct  incorrectly balanced log.

How far you can adjust or correct raw depends on how it’s been compressed (or not), the bit depth, whether it’s log or linear and how noisy it is. Just like a log recording really, it all depends on the quality of the recording. 

The big benefit raw can have is that the amount of data that needs to be recorded is considerably reduced compared conventional component or RGB video recordings.  As a result it’s often possible to record using a greater bit depth or with much less compression. It is the greater bit depth or reduced compression that really makes a difference. 16 bit data can have up to 65,536 luma gradations, compare that to the 4096 of 12 bit or 1024 of 10 bit and you can see how a 16 bit recording can have so much more information than a 10 bit one. And that makes a difference. But 10 bit log v 10 bit raw, well it depends on the compression, but well compressed 10 bit log will likely outperform 10 bit raw as the all important colour processing will have been done in the camera at a much higher bit depth than 10 bit.

Streaming and Live Feeds.

With some difficult times ahead and the need for most of us to minimise contact with others there has never been a greater need for streaming and online video services that now.

I’m setting up some streaming gear in my home office so that I can do some presentations and online workshops over the coming weeks.

I am not an expert on this and although I did recently buy a hardware RTMP streaming encoder, like many of us I didn’t have a good setup for live feeds and streaming.

So like so many people I tried to buy a Blackmagic Design Atem, which is a low cost all in one switcher and streaming device. But guess what? They are out of stock everywhere with no word on when more will become available. So I have had to look at other options.

The good news is that there are many options. There is always your mobile phone, but I want to be able to feed several sources including camera feeds, the feed from my laptop and the video output from a video card. 

OBS to the rescue!

The good news is that there is a great piece of open source software called OBS – Open Broadcast System and the Open Broadcast Studio streaming software.

OBSDemoApp2321 Streaming and Live Feeds.
Open Broadcast Studio Software.

 

OBS is s great piece of software that can convert almost any video source connected to a computer into a live stream that can be sent to most platforms including Facebook and YouTube etc. If the computer is powerful enough it can switch between different camera sources and audio sources. If you follow the tutorials on the OBS website it’s pretty quick and easy to get it up and running.

So how am I getting video into the laptop that’s running OBS? I already had a Blackmagic Mini Recorder which is an HDMI and SDI to thunderbolt input adapter and I shall be using this to feed the computer. There are many other options but the BM Mini Recorders are really cheap and most dealers stock them as well as Amazon. it’s HD only but for this I really don’t need 4K or UHD.

Blackmagic-mini-recorder Streaming and Live Feeds.
Blackmagic Mini Recorder HDMI and SDI to thunderbolt input adapter.

 

Taking things a step further I also have both an Atomos Sumo and an Atomos Shogun 7. Both of these monitor/recorders have the ability to act as a 4 channel vision switcher. The great thing about these compared to the Blackmagic Atem is that you can see all your sources on a single screen and you simply touch on the source that you wish to go live. A red box appears around that source and it’s output from the device. 

atomos_atomsumo19_on_set_in_studio_4kp60_1576110181000_1334246-e1584607746226 Streaming and Live Feeds.
The Atomos Sumo and the Shogun 7 can both act as 4 input vision switchers.

 

So now I have the ability to stream a feed via OBS from the SDI or HDMI input on the Blackmagic Mini Recorder, fed from one of 4 sources switched by the Atomos Sumo or Shogun 7. A nice little micro studio setup. My sources will be my FS5 and FX9. I can use my Shogun as a video player. For workflow demos I will use another laptop or my main edit machine feeding the video output from DaVinci Resolve via a Blackmagic Mini Monitor which is similar to the mini recorder but the mini monitor is an output device with SDI and HDMI outputs. The final source will be the HDMI output of the edit computer so you can see the desktop.

Don’t forget audio. You can probably get away with very low quality video to get many messages across. But if the audio is hard to hear or difficult to understand then people won’t want to watch your stream. I’m going to be feeding a lavalier (tie clip) mic directly into the computer and OBS.

I think really my main reason for writing this was really to show that many of us probably already have most of the tools needed to put together a small streaming package. Perhaps you can offer this as a service to clients that need to now think about online training or meetings. I was lucky enough to have already had all the items listed in this article, the only extras I have had to but are an extra thunderbolt cable as I only had one. But even if you don’t have a Sumo or Shogun 7 you can still use OBS to switch between the camera on your laptop and any other external inputs. The OBS software is free and very powerful and this really is the keystone to making this all work.

I will be starting a number of online seminars and sessions in the coming weeks. I do have some tutorial videos that I need to finish editing first, but once that’s done expect to see lots of interesting online content from me.  Do let me know what topics you would like to see covered and subject to a little bit of sponsorship I’ll see what I can do.

Stay well people. This will pass and then we can all get back on with life again.