This is another common question on many user groups. It comes up time and time again. But really there is no one clear cut answer. In a perfect world we would never need to add any noise reduction, but we don’t live and shoot in a perfect world. Often a camera might be a little noisy or you may be shooting with a lot less light than you would really like, so in camera NR might need to be considered.
You need to consider carefully whether you should use in camera NR or not. There will be some cases where you want in camera NR and other times when you don’t.
Post Production NR. An important consideration is that adding post production NR on top of in-camera NR is never the best route to go down. NR on top of NR will often produce ugly blocky artefacts. If you ever want to add NR in post production it is almost always better not to also add in camera NR. Post production NR has many advantages as you can more precisely control the type and amount you add depending on what the shot needs. When using proper grading software such as DaVinci Resolve you can use power windows or masks to only add NR to the parts of the image that need it.
Before someone else points it out I will add here that it is almost always impossible to turn off all in camera NR. There will almost certainly be some NR added at the sensor that you can not turn off. In addition most recording codecs will apply some noise reduction to avoid wasting data recording the noise, again this can’t be turned off. Generally higher bit rate, less compressed codecs apply less NR. What I am talking about here is the additional NR that can be set to differing levels within the cameras settings that is in addition to the NR that occurs at the sensor or in the codec.
Almost every NR process, as well as reducing the visibility of noise will introduce other image artefacts. Most NR process work by taking an average value for groups of pixels or an average value for the same pixel over a number of frames. This averaging tends to not only reduce the noise but also reduce fine details and textures. Faces and skin tones may appear smoothed and unnatural if excessively noise reduced. Smooth surfaces such as walls or the sky may get broken up into subtle bands or steps. Sometimes these artefacts won’t be seen in the cameras viewfinder or on a small screen and only become apparent on a bigger TV or monitor. Often the banding artefacts seen on walls etc are a result of excessive NR rather than a poor codec etc (although the two are often related as a weak codec may have to add a lot of NR to a noisy shot keep the bit rate down).
If you are shooting log then any minor artefacts in the log footage from in camera noise reduction may be magnified when you start grading and boosting the contrast. So, generally speaking when shooting log it is always best to avoid adding in camera NR. The easiest way to avoid noise when shooting with log is to expose a bit brighter so that in the grade you are never adding gain. Take gain away in post production to compensate for a brighter exposure and you take away much of the noise – without giving up those fine textures and details that make skin tones look great. If shooting log, really the only reason an image will be noisy is because it hasn’t been exposed bright enough. Even scenes that are meant to look dark need to be exposed well. Scenes with large dark areas need good contrast between at least some brighter parts so that the dark areas appear to be very dark compared to the bright highlights. Without any highlights it’s always tempting to bring up the shadows to give some point of reference. Add a highlight such as a light fixture or a lit face or object and there is no need to then bring up the shadows, they can remain dark, contrast is king when it comes to dark and night scenes.
If, however you are shooting for “direct to air” or content that won’t be graded and needs to look as good as possible directly from the camera then a small amount of in camera NR can be beneficial. But you should test the cameras different levels to see how much difference each level makes while also observing what happens to subtle textures and fine details. There is no free lunch here. The more NR you use the more fine details and textures you will lose and generally the difference in the amount of noise that is removed between the mid and high setting is quite small. Personally I tend to avoid using high and stick to low or medium levels. As always good exposure is the best way to avoid noise. Keep your gain and ISO levels low, add light if necessary or use a faster lens, this is much more effective than cranking up the NR.
UPDATE – Some issues with the original version of the LUT were found by some users, so I have created a revised version and the revised version is now linked below.
Arri Look LUT’s are clearly very popular with a lot of Sony users, so I have created an Arri-Look LUT for the FX3/FX6/FX9/Venice that can be used to mimic the look from an Arri camera. It is not designed to pretend to be a real Arri camera, but to instead provide an image with the look and feel of an Arri camera but tailored to the Sony sensors.
As usual the LUT is free to download, but if you do find it useful I do ask that you buy me a coffee or other drink as a thank you. All contributions are always most welcome. Additionally do let me know what you like about this LUT or don’t like, so I can look at what LUTs may be good to create in the future.
Hidden away in the Sony Alpha Academy are 6 tutorial videos that I made for the the Sony Cinemaline cameras, most notably the FX6 and FX3. These videos mainly cover the FX6 but information on the FX3 (and FX9) is also included in several of the videos..
The 6 videos cover the following subjects:
FX6 – Scan Modes and Codecs (including information of recording media) FX6/FX3 – What is S-Cinetone. FX6 – How to use the Cine-EI mode to shoot S-Log3. FX6/FX3 – Slow Motion and Timelapse. FX6/FX3 – Exposure tools (covering waveform and histogram as well as Zebras) FX6/FX3 – Post Production Stabilisation.
To watch these video you will need to setup a free account with Sony. Then go to the Alpha Academy page linked below and scroll down to the FilmMaking section and then open the My Sony Expert tab.
There is a bug in some versions of DaVinci Resolve 17 that can cause frames in some XAVC files to be rendered in the wrong order. This results in renders where the resulting video appears to stutter or the motion may jump backwards for a frame or two. This has now been fixed in version 17.3.2 so all user of XAVC and DaVinci Resolve are urged to upgrade to at least version 17.3.2.
Scroll down to where it says “Stunning Cinematic Colour” and there you will find a video called “Orlaith” that shows both LUT’s applied to the same footage.
Orlaith is a gaelic name and it is pronounced “orla”. It is the name of a mythical golden princess. The short film was shot on a teeny-tiny budget in a single evening with an FX3 and FX6 using S-Log3 and SGamut3.cine. Then the LUTs were applied directly to the footage with no further grading.
A question poped up today asking about how to expose S-Cinetone when shooting green screen. The answer is really quite simple – no differently to how you would expose S-Cinetone anywhere else. But, having said that it is important to understand that S-Cinetone is a bit different to normal Rec-709 and this needs to be considered when shooting for chroma key or green screen.
S-Cinetone’s highlight roll off and shoulder starts much lower than most “normal” rec-709 curves. From around 73% the gamma curve changes and starts to compress the levels and reduce contrast. In the shdows there is a variable toe that increases contrast at lower brightness levels. The nominal “normal” brightness levels are also lower, all part of the contemporary film like look S-Cinetone is designed to give. A 90% reflectivity reference white card would be exposed at approx 83% instead of the more normal 90% (if you were using a light meter you should end up with a 90% white card at 83IRE). A white piece of paper will be a bit brighter than this as printer and copier paper etc is designed to look as bright as possible, typically printer paper comes out around 3 to 5% brighter than a proper white card.
The lower start to the highlight roll-off means that if you place skintones around 70% the brighter parts of a face will be affected by the rolloff and this will make them flatter. Expose skin tones at 60% and the face will be more contrasty and in my opinion look better. Although darker this would still be well with the “normal” exposure range for S-Cinetone so you will not have excessive noise and it will still key well.
S-Cinetone would be considered correctly exposed when a 90% white card is exposed between 78% and 88%. This is quite a wide window and is due to the way S-Cinetone is designed to give differening contrast levels simply by exposing a touch brighter or darker. The variable toe and shoulder mean that exposing brighter will make the image flatter and exposing darker more contrasty. Exposing as you would with normal Rec-709 levels with a white card at 90% will place skintones rather higher than “normal” and they will appear very flat. So either expose so a white card falls in the 78-88% window or use a calibrated monitor to observe how the skin tone look and be careful not to overexpose them.
Your greenscreen should be between 40IRE and 60IRE for a good clean key, I normally aim for 50IRE with S-Cinetone, but provided you don’t go below 40IRE or above 60IRE you should be good.
The FX3’s larger brothers, the FX6 and FX9 have a function called “APR” that is used to periodically inspect every pixel on the sensor and normalise or map out any out of spec pixels. With modern 4K cameras having at least 8.8 million pixels the chances of a few going out of spec or being damaged by cosmic rays from time to time is quite high. So on the FX6 and FX9 you will get a reminder to perform the APR process around once a week.
From what I understand, the Alpha series cameras and FX3 also periodically perform a similar process automatically. Because these camera have a mechanical shutter to shut out any external light there is no need for any user intervention to perform this process so you will not be aware that it’s happening. On the FX6 and FX9 the user has to place a cap over the lens or sensor, hence why the camera asks you before it can happen.
But what if you find you have some bright or hot pixels with the FX3? Perhaps you have just travelled on a plane where the high altitude reduces the atmospheres damping effect of the high energy particles from space that can damage pixels. Well you can go into the camera’s menu system and force it to run its pixel mapping process which does the same thing as APR on the other cameras.
You need to go to:
MENU: (Setup) ? [Setup Option] ? select [Pixel Mapping] and then select OK. It doesn’t take long and I would recommend that you do this after flying on a plane or prior to any shoot where you will use large amounts of gain as this is when hot pixels are most likely to show up.
Most of sony’s cameras that support S-Log3 or Hybrid Log Gamma also have a function called Viewfinder Display Gamma Assist.
Viewfinder Display Gamma Assist allows you to monitor with the cameras built in LCD screen or viewfinder with the correct brightness and contrast range when using gamma curves that are not directly compatible with these Rec-709 screens.
Whenever you try to view a gamma curve that is not normal Rec-709 on a Rec-709 screen the brightness and contrast that you will see will be incorrect. The most common scenario is perhaps viewing S-Log3 without any form of LUT. In this case the images will look less bright and have less contrast than they should and this makes judging exposure difficult as well making it less easy to see focus errors.
With a camera like the FX6 or FX9 most people will use the cameras CineEI mode and add a LUT to the viewfinder image to convert the S-Log3 to something that looks more contrasty and on the FX6 and FX9 the default LUT is “s709”. However s709 is not the same thing as Rec-709 (Note that with the FX6, because LUTs are always available in the CineEI mode, viewfinder display gamma assist is not available in the CineEI mode of the FX6, you should instead use a LUT).
I think a lot of people think that the default s709 LUT is the same as Rec-709, it’s not, it is very different. They look very different and result in quite different brightness levels when exposed correctly. s709 when exposed correctly will put skin tones somewhere around 50-60% and white at 78%. If you expose s709 using normal Rec-709 brightness levels (70% skintones, 90% white) this is actually over exposed by just over 1 stop. As a result if you expose the s709 LUT, using Rec-709 levels, and then turn off the LUT and instead use Viewfinder Gamma Assist, the gamma assist will look wrong, it will be too bright and may look washed out and this is simply because the exposure IS wrong.
Almost always, if the viewfinder display gamma assist looks wrong, the exposure is wrong. When it looks right, the likelihood is the exposure is right.
A few things to understand:
The viewfinder is a Rec-709 range display device only capable of showing Rec-709 range and colour.
Feed true Rec-709 to a Rec-709 device and you will have a correct looking image with “normal” brightness, contrast and colour.
Feed S-Log3 to a Rec-709 device and you will have an incorrect dull, flat looking image due to the gamma miss-match between the capture gamma and display gamma.
Feed S-Log3 to a device with S-Log3 gamma and you will once again have the correct brightness and contrast as there is no longer a gamma miss-match (S-Log3 only appears to be flat due to the gamma missmatch between S-Log3 and Rec-709, use the right gamma and you will see that it is not actually flat).
Viewfinder Display Gamma Assist works by changing the gamma curve used in the Viewfinder to a gamma curve similar to S-Log3. When you view S-Log3 with a monitor with S-Log3 gamma you will have the correct contrast and brightness, so correct exposure will look correct.
But because the cameras LCD display screen can only show 6 to 7 stops you don’t get the full S-Log3 viewing range, just the central mid range part that is the direct equivalent of Rec-709. This very closely matches what you see if you use the Sony 709(800) LUT to convert the S-log3 to 709. The 709(800) LUT converts S-Log2 or S-Log3 to vanilla Rec-709 (70% skintones/90% white) with a knee that provides a slightly extended highlight range. It is broadly comparable to how most conventional Rec-709 cameras will look. So as a result viewfinder display gamma assist and Sony’s 709(800) LUT’s will look almost identical, while the s709 LUT will (and should by design) look different.
Viewfinder Display Gamma Assist is extremely useful for scenarios where you do not have a LUT option such as when shooting in CineEI in HD with the FX9. It can help you make good exposure assessments. It can make it easier to see when you are in focus. But it isn’t a LUT, so can’t be applied to the cameras outputs, only the built in viewfinder. Additionally if you use zebras, the waveform or histogram, gamma assist has no effect on these so you must remember that you are still measuring the levels of the actual recording gamma, not Rec-709 levels.
Viewfinder Gamma Assist is useful not only for shooting with S-Log but also when shooting using HLG (Hybrid Log Gamma). HLG is an HDR gamma curve and because the LCD viewfinder isn’t HDR you can’t correctly monitor HLG directly. Viewfinder Gamma Assist allows you to monitor with the correct brightness and contrast when shooting HLG making it easier to confidently get the correct exposure levels, as much like S-log3 the levels required for the correct exposure of HLG are quite different to Rec-709.
One last thing: NEVER use Viewfinder Gamma Assist with a LUT at the same time, this will result in a completely incorrect looking image and could result in very bad exposure as a result.
Can you tell which is genuine and which is fake? It would appear that a number of fake BP-U batteries are starting to show up on ebay and other less reputable places. The battery on the left won’t charge on a genuine Sony charger, this tells me it is not a real Sony battery.
If you look at the labels on the batteries the quality of the printing on the fake battery on the left is not as fine as on the genuine battery, in particular the ® as well as the box around the level indicator LED’s is not as crisply and finely printed.
The sellers are clever. These are not so cheap as to raise suspicion, they just seem very competitively priced. These batteries might be a little bit cheaper, but how safe are they and how long will they last? I have to say this would have fooled me and I have a lot of sympathy for others that have been tricked into buying these. But if the manufacturer can’t sell these by legitimate means under their own brand name I really do have to question their quality and safety.
This is a question that comes up a lot. Especially from those migrating to a camera with a CineEI mode from a camera without one. It perhaps isn’t obvious why you would want to use a shooting mode that has no way of adding gain to the recordings.
If using the CineEI mode shooting S-log3 at the base ISO, with no offsets or anything else then there is very little difference between what you record in Custom mode at the base ISO and CineEI at the base EI.
But we have to think about what the CineEI mode is all about. It’s all about image quality. You would normally chose to shoot S-Log3 when you want to get the highest possible quality image and CineEI is all about quality.
The CineEI mode allows you to view via your footage via a LUT so that you can get an appreciation of how the footage will look after grading. Also when monitoring and exposing via the LUT because the dynamic range of the LUT is narrower, your exposure will be more accurate and consistent because bad exposure looks more obviously bad. This makes grading easier. One of the keys to easy grading is consistent footage, footage where the exposure is shifting or the colours changing (don’t use ATW with Log!!) can be very hard to grade.
Then once you are comfortable exposing via a LUT you can start to think about using EI offsets to make the LUT brighter or darker. When the LUT is darker you open the aperture or reduce the ND to return the LUT to a normal looking image and vice versa with a brighter LUT. This then changes the brightness of the S-log3 recordings and you use this offsetting process to shift the highlight/shadow range as well as noise levels to suit the types of scenes you are shooting. Using a low EI (which makes the LUT darker) plus correct LUT exposure (the darker LUT will make you open the aperture to compensate) will result in a brighter recording which will improve the shadow details and textures that are recorded and thus can be seen in the shadow areas. At the same time however that brighter exposure will reduce the highlight range by a similar amount to the increase in the shadow range. And no matter what the offset, you always record at the cameras full dynamic range.
I think what people misunderstand about CineEI is that it’s there to allow you to get the best possible, highly controlled images from the camera. Getting the best out of any camera requires appropriate and sufficient light levels. CineEI is not designed or intended to be a replacement for adding gain or shooting at high recording ISOs where the images will be already compromised by noise and lowered dynamic range.
CineEI exists so that when you have enough light to really make the camera perform well you can make those decisions over noise v highlights v shadows to get the absolute best “negative” with consistent and accurate exposure to take into post production. It is also the only possible way you can shoot when using raw as raw recordings are straight from the sensor and never have extra gain added in camera.
Getting that noise/shadow/highlight balance exactly right, along with good exposure is far more important than the use of external recorders or fatter codecs. You will only ever really benefit fully from higher quality codecs if what you are recording is as good as it can be to start with. The limits as to what you can do in post production are tied to image noise no matter what codec or recording format you use. So get that bit right and everything else gets much easier and the end result much better. And that’s what CineEI gives you great control over.
When using CineEI or S-Log3 in general you need to stop thinking “video camera – slap in a load if gain if its dark” and think “film camera – if its too dark I need more light”. The whole point of using log is to get the best possible image quality, not shooting with insufficient light and a load of gain and noise. It requires a different approach and completely different way of thinking, much more in line with the way someone shooting on film would work.
What surprises me is the eagerness to adopt shutter angles and ISO ratings for electronic video cameras because they sound cool but less desire to adopt a film style approach to exposure based on getting the very best from the sensor. In reality a video sensor is the equivalent of a single sensitivity film stock. When a camera has dual ISO then it is like having a camera that takes two different film stocks. Adding gain or raising the ISO away from the base sensitivity in custom mode is a big compromise that can never be undone. It adds noise and decreases the dynamic range. Sometimes it is necessary, but don’t confuse that necessity with getting the very best that you can from the camera.