All posts by alisterchapman

Virtual Production With Venice 2. Dubai Workshop

V-OPT2-OMAR-600x333 Virtual Production With Venice 2.  Dubai WorkshopI have a crazy few weeks coming up. This week I will be filming at the Glastonbury festival, then next week I will be in Dubai for a workshop on virtual production with Sony’s Venice 2 camera. This will be a great opportunity for those that have never been to a virtual studio to have a look at how it all works and what’s involved – nad to see how Venice 2 is an excellent camera for VR thanks to it’s very fast sensor readout speed, frame size flexibility and wide range of frame rates. To join one of the sessions please RSVP to Omar.Abuaisha@sony.com 

CineD Venice 2 Dynamic Range Tests

The recent publication of CineD’s Venice 2 lab tests has created quite a stir and many have asked what my view on this is. You can see the entire test here:  https://www.cined.com/sony-venice-2-lab-test-rolling-shutter-dynamic-range-and-latitude/

I have not done any formal dynamic range testing with Venice 2 myself, but I have shot with it several times. I have also shot with most of Sony’s recent cameras including the original Venice, many different Red cameras and Arri ALexa’s. 

Whenever I shot with Venice 2 the dynamic range has always impressed me. I have been able to pull lots of detail out of the deepest shadows without any issue, no nasty noise artefacts, no coloured blotches.  When I shot the “London Vistas” video in London at night using available light I found the cameras noise floor to be very low, allowing me to get deep shadow textures without issue. The cameras highlight handling has also always impressed me and every time I’ve used Venice 2 I have been delighted with the dynamic range it delivers, it is up there with the Arri Alexa. From my real world shooting experience Venice 2 delivers more DR than my FX9 or FX6 and it delivers it in a very pleasing way. The way the far highlights and deep shadows behave is beautiful.

I would also point out that there are many great examples of deep shadow details and textures that are colour blotch free in Rob Hardy’s “Venizia” short film.

I would point out that CineD noted that the Venice 2 as the delivered the second highest dynamic range result they have seen in their lab when they recorded using the internal 4K ProRes recordings.  Venice 2 comes in just 0.3 stops behind the Alexa in this mode in the CineD tests. CineD have put this down to downsampling from 8K plus the use of additional internal noise reduction. While DCT codecs like ProRes do normally incorporate some degree of NR, I doubt that Sony are doing any significant NR in camera as this tends to degrade the image in other areas. So I find the discrepancy between the results they are seeing between the 16 it X-OCN and the 10 bit ProResHQ very intriguing and it makes me wonder if something else is going on. Downsampling from 8K will certainly help lower the noise a little, but I feel that there is something odd with the X-OCN results, one thing I note is a very raised pedestal on the waveform of the X-OCN, which is somewhat odd, the bit depth should help separate the noise from the useable signal. A camera either has a dynamic range or it doesn’t, only rarely does NR make a significant difference as the sensor analog to digital converters tend to be the one of the main limiting factors. My own real world experience is that Venice 2 when shooting X-OCN has more useable DR than almost every other camera I have used.

Bottom line is – don’t go by the test, try the camera for yourself as I am quite sure you will find, like me, that one thing Venice 2 does not lack is dynamic range. I will try to do my own formal tests as soon as possible.

Sony FX6 Intermittent Audio – Is Your Handle Secure?

DSC_0477-600x450 Sony FX6 Intermittent Audio - Is Your Handle Secure?There have been a few people popping up on various user groups and forums complaining of a sudden loss of audio or intermittent audio on their Sony FX6 cameras. A common cause of the loss of audio on the FX6 is a slightly loose top handle. The XLR inputs, MI Shoe and the cameras built in microphones are all part of the top handle, so if the handle is a little loose and the connection between the camera and handle isn’t perfect you can suddenly lose all your audio inputs.

As the connection between the handle and camera is a digital one you often won’t get any warning and if you are not wearing headphones you might not notice that you no longer have audio. Hint – wear headphones and monitor your audio when doing anything where the audio is even the slightest bit important 😉

So it is advisable to regularly check that the thumb screws that secure the handle are tight as if done up finger tight they do have a tendency to work lose over time. The thumbscrews have sockets for an allen key and I strongly suggest you use an allen key to tighten them up, done up this way they rarely come loose.

Sony Second Generation Dual Channel UWP-D Radio Mic Receiver.

DSC05650-copy-1024x875 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.
Sony URX-P41D UWP-D Dual Channel Radio Mic Receiver

 

I’ve been using Sony’s UWP-D series radio mics for more years than I can remember. In those years they have proved to be absolute workhorses and they have never let me down. The audio quality is very high, the transmission range very good thanks to the use of a diversity receiver and you have the added benefit of being able to attach the receiver to most of Sony’s more recent cameras via the MI Shoe.

When you use the MI Shoe the mic receiver is powered by the cameras battery and the audio passes into the camera via the shoe. If the camera has XLR connectors then these can be used to connect additional microphones allowing you to record from up to 4 audio sources without needing a mixer.  

 


If you want to get 2 channels of wireless audio into the camera you can either use 2 receivers and connect them via the XLR inputs or put a single channel receiver on the MI Shoe and then connect a second receiver via XLR. But an even neater way is to use one of Sony Dual Channel receivers.  I already have the previous dual channel receiver, the URX-P03D and I really wanted to see how this new version compares.

 

The URX-P41D a new dual channel receiver that replaces the previous model, the URX-P03D. It is slightly shorter but a little fatter than the previous receiver so overall similar in size and weight, but features some really nice new features. You will also be pleased to know that it is completely compatible with the previous generation of UWP-D transmitters including the UTX-B03 belt pack lavalier mics. It even includes an Infra Red port for wireless pairing. You can even bypass Sony’s digital compander, allowing it to be used with microphones from other brands. However to get the very best out of this receiver you want to use it with second generation UWP-D transmitters such as the UTX-B40 belt packs or UTX-P40 plugin transmitter.

DSC05607-copy-1024x636 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.
URX-P41D on an FX6 using the MI Shoe

 

The UTX-B40 belt pack transmitters are smaller than the previous generation and have a couple of new features that are quite handy. The first is the ability to set the audio gain to auto. Auto gain set the audio to a high gain level and then uses a limiter to ensure the the audio doesn’t clip or distort. This mode can be useful for presenters that talk quietly but may become much louder if they get excited. Another nice feature is the use of NFC for pairing rather than infrared. 

DSC05655-copy-1024x689 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.
You can see the pairing IR port for backwards compatibility on the side of the receiver

 

Pairing a transmitter to the receiver is very easy. You simply press and hold the NFC Sync button, the receiver will then scan for a clear channel. Once it has found a suitable clear frequency a message pops up on the nice clear OLED display to pair the RX and TX. This is done simply by holding the transmitter and receiver together so the NFC logo on each are facing each other. The receiver will then vibrate to confirm the pairing process has finished.

DSC05614-copy-1024x633 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.

The dual channel receiver has 2 on and off switches, one for each channel. So if only using one channel the other can be switched off to save power. There are separate 3.5mm sockets with locking rings  for each channel and the receiver is supplied with two locking 3.5mm to XLR cables. In addition there is a Y cable that connects both 3.5mm outputs to a single stereo 3.5mm plug. this is handy for cameras or other devices that only have a 3.5mm jack plug input. As well as the outputs there is a 3.5mm headphone socket.

DSC05611-copy-1024x684 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.

In addition to the outputs, rather curiously there is also a 3.5mm microphone input socket, the previous P03D also has this extra input. This additional input allows you to connect a 3rd microphone to the receiver. This third microphone is then mixed with the other 2 channels. This might be handy for some applications where you absolutely must have 5 sources feeding the camera but don’t have a mixer, but because this extra input is mixed with the wireless channels I think it has only limited usefulness. 

300x250-ad-box1 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.


When you want to connect the receiver directly to a Sony camera via the MI Shoe you have to use an adapter called the SMAD-P5 (Sony accessories have such easy names to remember, apparently it stands for Sony Multishoe ADapter). The SMAD adapter for the new second generation receivers is neater and more compact than the one used by the first generation.  It connects to a socket hidden under a rubber cover on the underside of the receiver. If you are using the URX-P41D with an FX6 as well as the MI-Shoe powering the receiver and providing the audio connection you get the added benefit of the receive signal strength of both channels being displayed on the cameras LCD screen.


DSC05660-copy-1024x660 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.
The UWP-D radio mic system is a hybrid Analog/Digital system. The transmitters and receivers use a digital compander system to process the audio to ensure as little loss of quality as possible during the transmission process. The companded signal is then transmitted from the transmitter to the receiver using analog FM. The frequencies these radio mics use offer greater range and are much less affected by obstructions or reflections than the 2.5Ghz band commonly used by many lower cost all digital radio mics.  I typically get over 100m(300ft) range. The digital compander is particularly good at preserving the sibilance in human speech. Often “S” sounds and other sharpe notes can become muted with lower quality radio mics, but the digital compander in the UWP-D series does a very good job of maintaining a wide frequency response. 

One particular advantage the new UWP-D  receivers bring over the previous generation is the ability to output the audio either conventionally as analog audio or digitally. To take advantage of the digital output you have to use the MI Shoe and your camera must support the digital output. There isn’t a huge boost in audio quality when you use the digital out, but you do get a little less background hiss and the audio is less likely to suffer from other electrical noise from the camera. It’s certainly a nice feature to have, but if your camera only has an analog input the audio quality is still very good. 

DSC05602-copy-1024x606 Sony Second Generation  Dual Channel UWP-D Radio Mic Receiver.
You can see the W1 and W2 signal strength indications from the attached URX-P41D towards the top left of the FX6 LCD. In this example on one channel was in use.

 

These second generation UWP-D radio mics are fully compatible with the previous generation, so you can upgrade just your receivers or add new transmitters if you wish. I think these are great and I would recommend anyone looking for a good quality professional radio mic system to at the very least have a close look at the Sony UWP-D series.

Cinegear Expo LA 2022

cingear-bt-1024x432 Cinegear Expo LA 2022

Cinegear expo will soon be upon us, it’s June 9th to June 11th at the LA Convention Center.  I will be attending the show and helping out Bright Tangerine on booth 480. So do drop by to see their latest products, but also come by for a chat or to ask any questions you have about using Sony cameras in the field or anything else you might need some help with. Sony will also of course have a booth and they will have their own experts on hand, but it is always good to catch up with friends and readers of the blog.

FX6 Fan Noise and Fan Modes.

fx6-fan-noise-600x384 FX6 Fan Noise and Fan Modes.Cooling fans (or perhaps more accurately temperature regulating fans) are an unfortunate necessity on modern high resolution cameras. As we try to read more and more pixels, process them and then encode them at ever greater resolutions more and more heat is generated. Throw in higher frame rates and the need to do that processing even faster and heat becomes an issue, especially in smaller camera bodies. So forced air cooling becomes necessary if you wish to shoot uninterrupted for extended periods..

Many camcorder users complain about fan noise. Not just with the FX6 but with many modern cameras. But fans are something we need, so we need to learn to live with the noise they make. And the fan isn’t just cooling the electronics, it is carefully regulating the temperature of the camera trying to keep it within a narrow temperature range.

The fan regulates the temperature of the sensor by taking warm air from the processing electronics and passing it over fins attached to the back of the sensor. I am led to believe that at start up the fan runs for around 30 seconds to quickly warm up the sensor. From there the camera tries to hold the sensor and electronics at a constant warm temperature, not too cold, not too hot, so that the sensor noise levels and black levels remain constant. The sensor is calibrated for this slightly warm temperature.

As well as running in the default auto mode there are  “minimum” and “off in record” modes for the fan in the technical section of the FX6’s main menu. Minimum forces the fan to run all the time at a low level so it doesn’t cycle on and off, possibly at higher levels. Off in record turns the fan off when recording – however the fan will still come on if there is a risk of damage due to overheating. Off in record can result in minor changes to noise as black levels during longer takes as the camera’s internal temperature rises, but you’ll likely only see this if you look carefully for it.

Using Auto Exposure With Cine EI.


First – What is “Exposure”

Something I find useful to consider is that “Exposure” is the amount of light that you put onto the sensor or film stock in your camera. It isn’t brightness, it is how much light. If you think about it, if you use a light meter to find you exposure settings, the light meter has no idea how bright the pictures will be, all it does is give you the shutter and aperture values needed to put the correct amount of light onto the sensor or film stock.

How Cine EI Works.

Next we need to think about how Cine EI works. You have to remember that when shooting using Cine EI the only thing that changes when you change the EI value is the brightness of the LUT and it is also worth considering that different LUTs may be completely different brightness. There is no change to the sensitivity of the sensor and no direct change to the brightness of what is recorded. To change the brightness of what is recorded YOU must change the aperture, shutter speed or ND etc. Normally you would monitor your images via a LUT and then you must adjust the exposure so the image on the viewfinder looks correct at the new Exposure Index, or use the waveform to measure the LUT and use this to set the exposure for the new EI. And by changing the exposure you are adding an exposure offset putting more (or less) light on to the sensor than would be normal at the base EI.

AE In Cine EI.

If you wish to use auto exposure in the Cine EI mode then you need to understand that the camera’s auto exposure system measures what is being recorded. It does not measure the LUT levels. The auto exposure system is unaware of your desire to expose the sensor more or less brightly than normal and will always base the exposure on the base ISO, not the Exposure Index. As a result if you are using AE and you go from 800 EI to 400 EI the image seen via the internal LUT will get darker by one stop, the AE will NOT compensate for the lower EI.  If you were to manually brighten the exposure by one stop the cameras exposure meter will think you are now over exposed – because you are!


Adding Offsets.

The only way around this is to add an offset to the AE system to account for the offset added by the different Exposure Index. For example if you want to shoot at 400EI (The LUT becoming 1 stop DARKER) then you would need to add a +1.0 stop offset to the cameras AE settings to offset the exposure 1 stop brighter. Each time you halve the EI you should add an extra +1 stop of offset. Each time you double the EI you should include an extra -1 stop offset.

There are a couple of ways to do this but the quickest is to use the Quick Menu function that is by default assigned to button 5 on the hand grip or button 8 on the handle. Press the direct menu button and then use the thumbstick to go the AE+0 indication just above the shutter speed indicator and add your offset.

Or you can long press the menu button to go into the cameras main menu then go to the – Shooting – Auto Exposure page and add your offset to the Level setting.

I don’t recommend the use of Auto Exposure in Cine EI. For a start AE uses the average brightness of the scene to set the exposure level, often this isn’t appropriate for Log. When shooting with log generally you want to ensure that it is your mid range is exposed at the right level and you don’t want bright highlights to result in an under exposed mid range. Additionally if the exposure changes mid shot this can make grading very difficult. If you do use auto exposure in Cine EI, then as well as adding any necessary offsets I also recommend slowing down the responsiveness of the AE using the “Speed” setting in the Auto Exposure menu. Using a value such as -60 will slow down the rate at which the AE will change the exposure which helps avoid rapid auto exposure changes for momentary light changes within the scene.

It is really important to remember that Exposure is NOT brightness. Exposure is how much light you put on the sensor. A light meter doesn’t know how bright you want your pictures to be. All it knows is the correct amount of light to put on to the sensor for the “correct” exposure. If using an external light meter provided you put the right values into your light meter it will give you the correct exposure settings, even though it has no idea how bright your pictures will be and the camera’s internal exposure meter acts in a similar way, so offsets are needed to match each EI you use.

300x250-ad-box1 Using Auto Exposure With Cine EI.

Camera Test Charts To Print At Home

Screenshot-2022-05-16-at-11.11.38-1024x622 Camera Test Charts To Print At HomeWhen testing and evaluating a camera, whether that’s a digital photo camera, video camera or digital cinema camera it is always useful to have a test chart or 2 (or more). While printing a chart at home isn’t always the best way to go, comercial charts can be very expensive to buy. So below is a link to an ISO 12233 chart, a Zone Plate chart and a Siemens Star chart that you can download  for free and print at home. You will need a good printer and good quality photo paper for the best results. 

For the ISO 12233 chart I divide this into quarters, print each 1/4 and then join them back together to make a larger chart.

The zone plate and siemens charts should be printed as large as possible, but in use they would not fill the frame, perhaps only a small part of the frame depending on the resolution of the camera you are evaluating.

I have not included any color charts or grey scale charts as it will be extremely difficult to know whether the colors or shades of grey your printer produces are actually correct, making the chart invalid.

Click on the green link or the images below:

Click here for ISO 12233 Test Chart as at the top of this page.

Zone-Small-150x150 Camera Test Charts To Print At Home
Zone plate derived from Imatest Software. Click on the image to go to full size file.
Siemens-100-chart-150x150 Camera Test Charts To Print At Home
Siemens 100 radial star chart – click on the image to go to the full size file.

LUT Download Issues when using Chrome – Fixed

Some of you may have been having issues downloading my LUT’s and some other content. This was occuring due to Chrome blocking the download of any files it deems unsafe. I have installed some upgraded tools on my server and you should find that downloads will work again now. Do let me know if you ever encounter issues with the site. The sooner you let me know the sooner I can look into them. Thanks.

Sony FX9 Error Codes.

Fortunately issues with Sony’s cameras are rare, but should you encounter a serious issue with your FX9 it will more often than not display an error code on the LCD screen. This will typically start with an E12,  E91 or  E95 prefix followed by 3 more numbers or letters.

E12 errors are normally related to the ND filter or the mechanism that moves the ND filter in and out of place (there is a screw accessible from the underside of the camera body that can be used in an emergency to wind the ND filter – DO NOT USE THIS – except in a get me out of jail at all costs situation).

E91 errors are generally related to the cameras main DPR394 board and in particular the main video and audio Input/output  and coded chip. Or communications between the main board and other sub units within the camera.

E95 errors are generally related to the cameras CPU/DSP and PCIe bus (again on the main DPR394 board).

Sometimes a non Sony lens or Lens adapter can cause the camera to throw up an error code, so one thing to try if you see an error code is to remove the lens or lens adapter to see if the error goes away. 3rd party batteries can also sometimes lead to an error code. 

Unfortunately other than lens/lens adapter or battery issues an error code will typically mean the camera needs ro be looked at by Sony or an authorised service center, but there are a few error codes that you might be able to deal with yourself:

E91:1D0 : This error is a communication error between the main board and the GPS unit in the cameras handle. Check that the handle is correctly attached and not lose. If you remove the handle you will get this error unless you turn off the GPS in the menu.

E91:360, E91:367, E91:36C are caused by faults in the XDCA-FX9, so if you have an XDCA-FX9 on the camera, removing the XDCA will normally clear these error – but your XDCA will need to be repaired.