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.
Category Archives: FX3
Understanding Sony’s Viewfinder Display Gamma assist.
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.
Beware Fake Sony BP-U Batteries!
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.
Thanks to Zachary Këpël for the use of his image.
What Benefits Do I Gain By Using CineEI?
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.
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.
For more information on CineEI see:
Using CineEI with the FX6
For more information on CineEI see:
Using CineEI with the FX6
How Do You Expose S-Cinetone with the FX6/FX3/A7SIII
Lots of people have been asking about how to expose S-Cinetone, whether with the FX9, FX6, A7SIII or the FX3.
The short answers is: So that it looks nice!
S-Cinetone has a variable toe and knee. So exposing it brighter results in not only a brighter image but also an image with flatter skin tones and less shadow contrast, overall looking more video like.
Exposing a little bit darker results in a more contrasty film like image. Faces and skin tones have more texture. There is no one optimum exposure level. A white card could be anywhere between 78% and 88% depending on the look you want. Typical skin tones will vary from between anywhere between 55% and 75%.
Personally I like the way S-Cinetone looks when it’s exposed with Skin tones at around 63% and white at around 81%.
See the video I on S-Cinetone on the FX9 for more details as it all applies equally to the FX9 and FX6 as well as the A7SIII and FX3. The only small difference is that the base ISO’s are a little different between each camera.
Alister’s FX3 Reminders
I’m putting these notes here for my own reference. I will add to them as I find new things to remember. They may help others too. As I already have a Sony FX9 and an FX6 I thought it would be a good idea to have some notes about some of the difference I need to remember when using an FX3 (and A7SIII) alongside the FX6 or FX9.
BASE ISO:
| Gamma/Base ISO | S-Cinetone Low Base | S-Cinetone Hi Base | S-Log3 Low Base | S-Log3 High Base |
| FX3/A7SIII | 100 | 2,000 | 640 | 12,800 |
| FX6 | 320 | 5,000 | 800 | 12,800 |
| FX9 | 320 | 1,600 | 800 | 4000 |
ISO RATING:
The FX3/A7SIII ISO ratings are just over 1 stop brighter than the same ratings on the FX6/FX9 except when using S-Log3 which matches correctly. So if using 320ISO for S-Cinetone on the FX6/FX9 use 100ISO on the FX3/A7SIII for the same brightness of recording.
HDMI:
To use both the HDMI out and the camera’s LCD screen at the same time you have to turn off the HDMI Info in the External Output settings.
STABILISATION:
To use post production stabilisation you must turn off Steadyshot in the menu.
XAVC-S-I Codec has the same bit rates and appears to be the same quality as XAVC-I.
APPLICATION:
FX3 Uses “Imaging Edge” app and FX6/FX9 use “Content Browser Mobile” app.
EXTERNAL POWER:
The FX3 can be powered externally via the USB-C port. With a compatible USB-PD power source the camera can be run continuously.
Which Sony ISO RatingS Are Correct?
In the course of my tests with the FX3 and comparing it with the FX6 and FX9 I discovered a strange anomaly with the FX3 and A7SIII ISO ratings when compared to the FX6 and FX9.
The FX3’s default picture profile is PP11 and S-Cinetone. If you have an FX6 or FX9 these cameras also default to S-Cinetone in SDR mode. In the FX6 and FX9 the base ISO for S-Cinetone is 320 ISO. Therefore you would assume that if you also set the A7SIII or the FX3 to 320 ISO and expose all the cameras the same, same aperture, shutter etc that the exposures would match.
BUT THE EXPOSURES DON’T MATCH!!
The FX3 and the A7SIIII are just over 1 stop brighter than the FX6 and FX9 when all the exposure settings are matched. I tested all the cameras with the same lens to ensure this wasn’t a lens issue, but it isn’t the lens.
I then went on to test other gamma/picture profile settings and I found a just over 1 stop difference between the FX3 and my FX6/FX9 in any similar combination EXCEPT S-LOG3!
When using Picture Profile 2 on the FX3 which is uses Sony’s “Still” gamma and then using the “Still” Profile on the FX6 there is a difference of around 1 stop. If I set the FX3 to PP3 (ITU-709) and the FX6 to ITU-709 then the difference is again around 1 stop, in every case the FX3 is brighter except when you select S-Log3 where the FX3 and the FX6/FX9 match almost perfectly!
I find this very strange. They should not be different. My light meter suggests to me that the FX6/FX9 are correct.
Comparing to my light meter I believe the FX6/FX9 ratings to be correct and the FX3 to be between 1 and 1.3 stops brighter than it should be when using gammas that are not S-Log3. What I really don’t understand is why the FX3/A7SIII match the FX6/FX9 when using S-Log3 but do not match when using the other profiles, normally I would expect to see a consistent offset. This further makes leads me to be sure this is not a problem with my light meter, but something else.
I would love to hear from anyone else that’s able to take a look at the ISO ratings of the A7SIII and compare it with an FX6 or FX9.
The bottom line is – DON’T EXPECT TO PUT THE SAME EXPOSURE SETTINGS INTO BOTH AN FX3 AND AN FX6/FX9 AND GET THE SAME RESULTS, because you won’t, unless you are using S-Log3, then they match.
Also in the clip metadata I found that 0dB for S-Cinetone is 100 ISO, and whether this is a coincidence or not, if I set the FX3 to 100 ISO and the FX6 to 320 ISO and then match shutter speed and aperture then the exposures are very close.
This one has left me confused!!!!
What do I think of the new FX3?
What do I think about the new Sony FX3. It’s certainly an interesting camera because it seems to be a bit confused about what it is.
It’s isn’t a mirrorless stills camera like the A7SIII, but it’s very, very like the A7SIII.
It isn’t a cut down FX6 or FX9, it’s very different to them.
So what is it and who is it for? Personally I see the FX3 as a great B camera option to pair with an FX6 or FX9. The FX3’s flat top and additional 1/4″ mounting points on the top and sides will making rigging it in more unusual situations much easier. It’s a camera I would use to rig in cars like a giant Go-Pro, perfect for any Top Gear or motoring shoots. It’s a camera I would use on a gimbal, it’s a camera you could sling from a drone.
In most cases it would not replace any camera I currently have, but instead compliment it. It could be a good option for FX9 owners in particular as it would give them 4K 120fps as well as a second camera when needed.
The FX3 is not much more than an A7SIII in a different housing, with the EVF removed, new mounting points added and an removable handle with XLR connectors. There are some changes to some of the button positions and these make it easier to use when shooting video providing direct access to ISO, IRIS and White Balance. The flat top makes it easier to mount in different ways and the built in 1/4″ mounting threads make it easier to mount accessories such as monitors.
Really the FX3 is an alternative version of the A7SIII biased more towards video than photos. It doesn’t replace the A7S, just gives potential owners the ability to choose between the two different form factors depending on individual preferences.
For more information why not watch this recording of my Facebook live stream on the FX3.