Topics

Sony FS7 MK I+II Noise

pressuresound@...
 

Hello All,

I am trying to track down a phenomena. There are two video files of similar situation, one was shot with a FS7 MK1
the other with the MK2. They appear to be very different in noise level and overall sharpness and I am trying to track down
the reasons for this. In short, the newer camera with the bigger resolution looks worse.
I know about the ISO and that it should be overexposed, but is there anything like interpolation at 4K or about the Gamut?
Maybe somebody has a hint or experiences if that's all that's to it.
Here are the specs:

File A (sharp, little noise)
  • FS7-MK1
  • Resolution 3840x2178
  • SGamut 3 Cine
  • Slog3
  • 25fps
  • ISO 1600

File B (muddy, very noisy in shadows and grays)
  • FS7-MK2
  • Resolution 4096x2178
  • SGamut 3
  • Slog3
  • 50fps
  • ISO 2000

Grateful for any leads,

Greetings,
Tobi Jall
DoP
Berlin
tobijall.com

James Barber
 

Gamut and the small ISO difference of a 1/3rd stop shouldn't radically increase noise. What probably did it was that is was shot at 50P, vs the 25P of the one with less noise. So that's one stop less light, coupled with the 1/3rd, for 1.3stop total, and that, absolutely can result in a very different amount of noise. If you couple that with a lens that has the same F-stop but a slower T-stop for example, you reduce total light even more.

I've edited/graded thousands of FS7 shots over the years, and never once has a resolution change from UHD to DCI4k caused an increase in noise. The Gamut is just the colour space, and shouldn't affect it either. Shooting stuff in various flavours of S-log, and underexposing it, always leads to massive noise with the camera though. Also leads to issues with midtone saturation and tones (as you're bringing up shadow saturation to midtone saturation and even the 10bit signal doesn't have enough info to look great doing that).

If it wasn't any of those issues though, I'd be very interested in other opinions.

Regards
James Barber
Director/Editor/Colourist/DoP yadayadyada
London

Alex Metcalfe DoP
 

Shooting stuff in various flavours of S-log, and underexposing it, always leads to massive noise with the camera though

Yes, I completely agree. The FS7 can give very good pictures for its price-point but it picks up noise in the shadow areas extremely easily. There is no difference in sensor or electronics between the MKI and MKII so that can be ruled out. Sony call it a 2000 iso camera but in my experience when you are in a dark or high contrast environment you need to overexpose as much as you can to keep the shadow areas high before starting to lose highlight detail, so by the time you take that into account I'd call it more like 800 iso - that is just anecdotal, not tested.

I have also had an issue when I used the camera initially and found that the plug in Neate Video did a fantastic job of cleaning up the noise without bringing in too much softness. Not ideal but it got me out of a hole that time!

Alex Metcalfe
DoP EU




On 15/10/2018 09:13, pressuresound@... wrote:

Hello All,

I am trying to track down a phenomena. There are two video files of similar situation, one was shot with a FS7 MK1
the other with the MK2. They appear to be very different in noise level and overall sharpness and I am trying to track down
the reasons for this. In short, the newer camera with the bigger resolution looks worse.
I know about the ISO and that it should be overexposed, but is there anything like interpolation at 4K or about the Gamut?
Maybe somebody has a hint or experiences if that's all that's to it.
Here are the specs:

File A (sharp, little noise)
  • FS7-MK1
  • Resolution 3840x2178
  • SGamut 3 Cine
  • Slog3
  • 25fps
  • ISO 1600

File B (muddy, very noisy in shadows and grays)
  • FS7-MK2
  • Resolution 4096x2178
  • SGamut 3
  • Slog3
  • 50fps
  • ISO 2000

Grateful for any leads,

Greetings,
Tobi Jall
DoP
Berlin
tobijall.com


-- 
Alex Metcalfe DoP
+44 (0) 7785 557611
www.alexmetcalfedop.co.uk

 

As I understand it, the sensor on the FS7 is the same as the F5, and they can certainly produce great pics, especially if you over expose a bit.

Michael Sanders: Director of Photography.  London based but works globally.

reel/credits/kit: www.mjsanders.co.uk    m: +44 (0) 7976 269818

On 15 Oct 2018, at 10:53, Alex Metcalfe DoP <alex@...> wrote:

The FS7 can give very good pictures for its price-point but it picks up noise in the shadow areas extremely easily. There is no difference in sensor or electronics between the MKI and MKII so that can be ruled out.

Colin Elves
 

I hesitate to make this suggestion as I don’t have much to back it up beyond my own eyes, but the FS7 seems to exhibit a lot of artefacting starting in the lower midtones, which gets worse in the shadows, which makes me think that there’s some noise reduction applied in camera as standard (possibly beyond that required by the codec). 

You can see it in the -6 AGDok comparison test: lots of weird blockiness in the FS7 compared to the Raw Cameras (and the EVA1 LogGoP as it happens)


So my guess would be that either you’ve got an exposure difference between the two and the MK2 is digging more into the NR area and/or Sony ‘updated’ the NR in the MK2 and to your eyes the change is not all positive. 

Anyway, I’m gonna duck my head below the parapet now, before it gets knocked off.

Colin Elves
Director of Photography
Berlin, but off to Manchester today!



On 15 Oct 2018, at 10:13, pressuresound@... wrote:

Hello All,

I am trying to track down a phenomena. There are two video files of similar situation, one was shot with a FS7 MK1
the other with the MK2. They appear to be very different in noise level and overall sharpness and I am trying to track down
the reasons for this. In short, the newer camera with the bigger resolution looks worse.

Jan Klier
 

From all the documentation I’ve seen the two models (Mk1 & Mk2) have the same sensor and image processing. Most of the changes were on the ergonomic and mechanical side of things.

The list of differences by the OP also leaves a lot of detail out. Did both units have the same internal NR setting? Did they record the same codec and did they both record internal?

I’ve shot many jobs on my Mk1 and while it can produce beautiful images, it’s not what comes straight out of the camera, where there are many other cameras that make it a lot easier and are less fuzzy about things. I frequently have two-camera shoots where the FS7 MK1 is paired with a Varicam LT. The FS7 is a lot more cranky in terms of image quality.

So I would say, the two units were exposed and configured differently (as evidenced in ISO, color space, and fps settings mentioned, and probably a few others). It’s not an inherent difference between the two models. It’s just that settings make a much bigger difference than on some other cameras.

Jan Klier
DP NYC

On Oct 15, 2018, at 8:18 AM, Colin Elves <colin@...> wrote:

So my guess would be that either you’ve got an exposure difference between the two and the MK2 is digging more into the NR area and/or Sony ‘updated’ the NR in the MK2 and to your eyes the change is not all positive.

Robert A. Ober
 

On 10/15/2018 3:13 AM, pressuresound@... wrote:

Hello All,

I am trying to track down a phenomena. There are two video files of similar situation, one was shot with a FS7 MK1
the other with the MK2. They appear to be very different in noise level and overall sharpness and I am trying to track down
the reasons for this. In short, the newer camera with the bigger resolution looks worse.
I know about the ISO and that it should be overexposed, but is there anything like interpolation at 4K or about the Gamut?
Maybe somebody has a hint or experiences if that's all that's to it.
Here are the specs:

____________________________________

Are you viewing the log image or with a LUT?

Have you looked at the files in Invisor or Mediainfo to verify they are what you believe them to be?

Have you tried to view them in Sony Catalyst and Resolve?

Robert A. Ober
IT Consultant, Vidcaster, and Freelance Preditor(Producer/Editor)
Houston, TX

pressuresound@...
 

Hello,
thanks for all the replies. I have to specify a few things:

I looked at the ungraded log files in VLC, the codecs were the same, the internal filter settings are unknown but where def not "clear".
Both files were recorded internally.
In the meantime, I convinced the producer to let me shoot a proper test in the next weeks.

Thanks so far!
Greetings,
Tobi Jall
DoP
Berlin
tobijall.com

 

Have you tried Catalyst Browse? That shows a lot of metadata, possibly including filter settings.

Michael Sanders: Director of Photography.  London based but works globally.

reel/credits/kit: www.mjsanders.co.uk    m: +44 (0) 7976 269818

On 16 Oct 2018, at 11:00, pressuresound@... wrote:

I looked at the ungraded log files in VLC, the codecs were the same, the internal filter settings are unknown but where def not "clear".
Both files were recorded internally.
In the meantime, I convinced the producer to let me shoot a proper test in the next weeks.

Jan Klier
 

Catalyst Browse makes it easy to see as suggested. Even if you only have the MXF file, most info is in that file.

The MediaInfo.app for Mac is excellent at getting at this info quickly. In fact, this reminds of a recent job where I was told the footage was definitely SLog3 but looked wrong and very noisy in the shadows once it was pulled up where exposure looked right. After digging through the data I found out it was actually recorded in SLog2. Once changing Resolve to the SLog2 IDT things started falling into place more easily.

Unfortunately the one helpful setting is displayed neither here nor in catalyst, which is internal NR.

Here’s the MediaInfo.app output (abbreviated) for a recently recorded FS7 file:

Frame rate                               : 29.970 fps
CaptureGammaEquation_FirstFrame          : 0E06040101010605
AutoExposureMode_FirstFrame              : Manual
NeutralDensityFilterWheelSetting_FirstFr : Clear
ImageSensorReadoutMode_FirstFrame        : Progressive frame
ShutterSpeed_Angle_FirstFrame            : 180.0°
ShutterSpeed_Time_FirstFrame             : 1/60 s
CameraMasterGainAdjustment_FirstFrame    : 0.00 dB
ISOSensitivity_FirstFrame                : 2000
AutoWhiteBalanceMode_FirstFrame          : Preset
WhiteBalance_FirstFrame                  : 5500 K
CameraMasterBlackLevel_FirstFrame        : 3.0%
ExposureIndexofPhotoMeter_FirstFrame     : 1000
GammaForCDL_FirstFrame                   : Undefined
ASC_CDL_V12_FirstFrame                   : sR=1.0 sG=1.0 sB=1.0 oR=0.0 oG=0.0 oB=0.0 pR=1.0 pG=1.0 pB=1.0 sat=1.0


GammaEquation for SLog3 is 0E06040101010605
GammaEquation for SLog2 is 0E06040101010508

Jan Klier
DP NYC

On Oct 16, 2018, at 6:44 AM, Michael Sanders via Cml.News <glowstars=me.com@...> wrote:

Have you tried Catalyst Browse? That shows a lot of metadata, possibly including filter settings.

On 16 Oct 2018, at 11:00, pressuresound@... wrote:

I looked at the ungraded log files in VLC, the codecs were the same, the internal filter settings are unknown but where def not "clear".
Both files were recorded internally.