SIGMA FP with ProRes RAW and BRAW !

[OleB]

11 hours ago, TomTheDP said:

The exposure looks a lot the same in REC709 but when switched to a log profile it looks a lot darker on the FP. 

Yeah that seems to be, because in camera, and with an external monitor as well, there is no way of correctly exposing the camera in any other ISO setting than 100. The display forces you to underexpose until the preview looks okay, but in reality, this is what the log shows as well, it is then underexposed.

I compared the metering options of the camera and its preview to my Ninja V route with the ARRI LUT by toggling the Ninja on/off. With the Ninja exposure was totally fine, on the fp with the same settings obviously, it was already reading as severely overexposed, both in the display and with the false colors turned on. So that being said, only the Ninja V way can be exposed like expected if you want to shoot something else than ISO 100.

 

[kye]

13 hours ago, TomTheDP said:

The white balance was set the same on both cameras but yes they are a lot different in how they interpret it. 

I've seen this a lot on camera comparisons.  Two images look like they have a different WB, but when you compare them the neutral greys are both neutral but there will be different tints with the highlights/shadows or on hues that are beyond a certain level of saturation.

It makes looking and comparing images very confusing - they look different but sensible adjustments don't seem to be effective in making them match.  The good thing with the FP is (I assume) you can CST back to a neutral point and then apply whatever colour science you want, side-stepping any oddities from a particular colour science or other.

[TomTheDP]

7 hours ago, kye said:

I've seen this a lot on camera comparisons.  Two images look like they have a different WB, but when you compare them the neutral greys are both neutral but there will be different tints with the highlights/shadows or on hues that are beyond a certain level of saturation.

It makes looking and comparing images very confusing - they look different but sensible adjustments don't seem to be effective in making them match.  The good thing with the FP is (I assume) you can CST back to a neutral point and then apply whatever colour science you want, side-stepping any oddities from a particular colour science or other.

Using color space transform and the ARRI lut gets them to match contrast wise. The color still looks vastly different. I feel they look quite close after adjusting WB/tint around, but my color blind eyes aren't a great judge. 

9 hours ago, OleB said:

Yeah that seems to be, because in camera, and with an external monitor as well, there is no way of correctly exposing the camera in any other ISO setting than 100. The display forces you to underexpose until the preview looks okay, but in reality, this is what the log shows as well, it is then underexposed.

I compared the metering options of the camera and its preview to my Ninja V route with the ARRI LUT by toggling the Ninja on/off. With the Ninja exposure was totally fine, on the fp with the same settings obviously, it was already reading as severely overexposed, both in the display and with the false colors turned on. So that being said, only the Ninja V way can be exposed like expected if you want to shoot something else than ISO 100.

 

I use 100 iso to see my highlights and then push from there between 400-800 to see what I have in the shadows. I used this method on the last feature I did and was happy with the results. 

640 iso does looks underexposed after changing the color space. However after boosting the exposure to match both cameras it actually seems similar to the Alexa in terms of noise performance. So in that sense it actually works out. I could have lit it bright and got a cleaner image but I wanted to see both cameras in a dim situation. The Sigma FP could have been cleaner if I bumped it up to 3200 iso but I wanted to see them at the same ISO. 
 

[Llaasseerr]

Hi all, I got sidetracked with a work project but coming back to the fp, I was looking at the combo with the Ninja V again and I could not immediately see how to output V-log over HDMI from the Ninja V to another monitor. Meaning, basically pass through the V-log encoded image seen on the Ninja V to a director's monitor or an EVF.

I've selected V-log ("Native") for the monitoring and that all looks fine on the device itself. 

For me, HDR output over HDMI can't be disabled. So the color space needs to be PQ, HLG etc and the gamut also needs to be selected, which should be V-gamut but that's also not available. Its really odd if you can't just pass through the image. I'm going to also contact Atomos support and see what the deal is.

[OleB]

On 1/4/2023 at 3:15 PM, Llaasseerr said:

Hi all, I got sidetracked with a work project but coming back to the fp, I was looking at the combo with the Ninja V again and I could not immediately see how to output V-log over HDMI from the Ninja V to another monitor. Meaning, basically pass through the V-log encoded image seen on the Ninja V to a director's monitor or an EVF.

I've selected V-log ("Native") for the monitoring and that all looks fine on the device itself. 

For me, HDR output over HDMI can't be disabled. So the color space needs to be PQ, HLG etc and the gamut also needs to be selected, which should be V-gamut but that's also not available. Its really odd if you can't just pass through the image. I'm going to also contact Atomos support and see what the deal is.

Hi Sir,

coming back on this, the issue seems to be that the fp is not using V-gamut. It is using Sigma RAW gamut. Seems Atomos only applied the V-log gamma curve, but the gamut is kept native. 

Have had a lot of things going on lately to create a LUT to get this correct, since the exact parameters of the fp gamut are nowhere documented by Sigma. 

I have exported one clip from FCPX, RAW-to-Log conversion set to Panasonic V-Log, to ProRes 4444 to work further in DaVinci Resolve since FCPX is not able to create LUTs.

Setting up the following nodes =>

Node 1: ACES Transform Input: Panasonic / Output: ARRI LogC:

Node 2: Color Space Transform (that step is not industry standard, but it seems to uncompress the for me unknown gamut of the fp nicely to what the ARRI Rec709 Classic LUT expects and puts saturation where it should be - amazingly that ARRI WG3 gamut matches the sensor capabilities of the fp extremely well)

Node 3: ARRI Rec709 Classic LUT. Directly downloaded from ARRI website.

Result is working perfectly as you can see in this screenshot.

 

I have uploaded the sample clip plus LUTs here: https://www.dropbox.com/home/Sigma%20fp%20LUT

The monitoring LUT is the compilation of the above mentioned steps and can be used on the Atomos Ninja V and on the clips. (You will only have some minor banding using custom LUTs on the Ninja V, which is a firmware issue, which is known and was published in the release notes of the firmware bringing support for the fp)

The sample clip will also show a very bright scene with direct sunlight, showing the amazing highlight rolloff which can be achieved by the combination of the ARRI LUT and if the camera is correctly used as intended in that circumstance at ISO 800. ISO 3200 was used in all very low light scenes. White balance in camera was set to 5600k to have a consistent output. Skin colors just look amazing, so as all the other example clips I have tested >70 different ones.

@TomTheDP Some of the above also applies to cDNG. The gamut of the fp is basically unknown and for some reason I do not know the colors are somewhat compressed there as well. Maybe it is a gamut transfer mistakenly applied twice in camera. But knowing that you could work your way onward from that.

[Llaasseerr]

On 2/2/2023 at 2:36 PM, OleB said:

Hi Sir,

coming back on this, the issue seems to be that the fp is not using V-gamut. It is using Sigma RAW gamut. Seems Atomos only applied the V-log gamma curve, but the gamut is kept native. 

Have had a lot of things going on lately to create a LUT to get this correct, since the exact parameters of the fp gamut are nowhere documented by Sigma. 

I have exported one clip from FCPX, RAW-to-Log conversion set to Panasonic V-Log, to ProRes 4444 to work further in DaVinci Resolve since FCPX is not able to create LUTs.

Setting up the following nodes =>

Node 1: ACES Transform Input: Panasonic / Output: ARRI LogC:

Node 2: Color Space Transform (that step is not industry standard, but it seems to uncompress the for me unknown gamut of the fp nicely to what the ARRI Rec709 Classic LUT expects and puts saturation where it should be - amazingly that ARRI WG3 gamut matches the sensor capabilities of the fp extremely well)

Node 3: ARRI Rec709 Classic LUT. Directly downloaded from ARRI website.

Result is working perfectly as you can see in this screenshot.

 

I have uploaded the sample clip plus LUTs here: https://www.dropbox.com/home/Sigma%20fp%20LUT

The monitoring LUT is the compilation of the above mentioned steps and can be used on the Atomos Ninja V and on the clips. (You will only have some minor banding using custom LUTs on the Ninja V, which is a firmware issue, which is known and was published in the release notes of the firmware bringing support for the fp)

The sample clip will also show a very bright scene with direct sunlight, showing the amazing highlight rolloff which can be achieved by the combination of the ARRI LUT and if the camera is correctly used as intended in that circumstance at ISO 800. ISO 3200 was used in all very low light scenes. White balance in camera was set to 5600k to have a consistent output. Skin colors just look amazing, so as all the other example clips I have tested >70 different ones.

@TomTheDP Some of the above also applies to cDNG. The gamut of the fp is basically unknown and for some reason I do not know the colors are somewhat compressed there as well. Maybe it is a gamut transfer mistakenly applied twice in camera. But knowing that you could work your way onward from that.

The issue I'm particularly taking about is separate to this. If I wanted to for example connect a director's monitor from the HDMI out of the Ninja V, there does not seem to be a way to disable the HDR Out to the external display. If you're monitoring in Vlog on the Ninja (with or without an additional LUT) and want to see the same image on the connected screen, then currently there doesn't appear to be a way because HDR Output over HDMI can't be disabled. This transforms the image to HLG or PQ when I want to stay in Vlog.

If this works okay for you, I would be interested to know.

[OleB]

21 hours ago, Llaasseerr said:

The issue I'm particularly taking about is separate to this. If I wanted to for example connect a director's monitor from the HDMI out of the Ninja V, there does not seem to be a way to disable the HDR Out to the external display. If you're monitoring in Vlog on the Ninja (with or without an additional LUT) and want to see the same image on the connected screen, then currently there doesn't appear to be a way because HDR Output over HDMI can't be disabled. This transforms the image to HLG or PQ when I want to stay in Vlog.

If this works okay for you, I would be interested to know.

Can confirm that is the same for me. Have to update the Ninja V to the latest firmware however, maybe that changes something. At least in the specs Atomos says, that the monitor should be able to loop out YCC. 
 

[alanpoiuyt]

Seeing that this thread is active again for fp lovers, here's a DJI LiDAR autofocus test using the Aivascope 1.5 with Helios 44 taking lens. This is the LiDAR unit from the RS3 pro gimbal - off gimbal, handheld. 

 

[OleB]

On 1/4/2023 at 3:15 PM, Llaasseerr said:

Hi all, I got sidetracked with a work project but coming back to the fp, I was looking at the combo with the Ninja V again and I could not immediately see how to output V-log over HDMI from the Ninja V to another monitor. Meaning, basically pass through the V-log encoded image seen on the Ninja V to a director's monitor or an EVF.

I've selected V-log ("Native") for the monitoring and that all looks fine on the device itself. 

For me, HDR output over HDMI can't be disabled. So the color space needs to be PQ, HLG etc and the gamut also needs to be selected, which should be V-gamut but that's also not available. Its really odd if you can't just pass through the image. I'm going to also contact Atomos support and see what the deal is.

Just to follow up, newest firmware did not change anything. HDR is stuck at enabled... Thinking about how to setup a focus pulling setup than. Would it be possible to use a teradek bolt and loop the HDMI before the Ninja V? Have not found anything in the internet about looping out ProRes RAW... Maybe it is simply not possible and doing it after the Ninja V, even with correct HDR off setting, that would introduce even more delay.

[OleB]

@TomTheDP
 

Take a look at this essay below, used the same settings with your ARRI footage and they are extremely close now. Thanks again for giving access to that footage. 🙂

 

Hi all,

I have some very exciting news for you. After a couple more testing sessions I have figured out how to match my ProRes RAW workflow coming from V-log ending in the ARRI Rec709 LUT as well for cDNG!!

Assume this workflow can also be compiled into a monitoring LUT to be uploaded on 3D compatible monitor. The highlights will still be shown as clipped with more than +3 stops over middle grey. But that could be remedied by securing highlights setting the camera to ISO 100 and afterwards switch back to ISO 800. They will be left intact as the camera is invariant in that range and you can see what is happening in the shadows.

Necessary steps are the following:

1. RAW settings & CST to ARRI LogC

2. CST (non industry standard) bringen the colors into range where they belong

3. ARRI Rec709 Classic LUT

4. Comparison shot of my PRR workflow footage: same same 🙂 

[alanpoiuyt]

fp Fans - here's one from the mountaintop.

 

 

[OleB]

Hi all,

have attached a chart that sums up my essay about the fps ISO behaviour.

Concentrated only on the native ISO circuits instead of the ones with further analogue gain, which I would not recommend using.

Rating of the native ISO value for the 1st circuit are per my definition in accordance to the 2nd circuit stops distribution.

The chart is valid for RAW (CINE) recordings of the Sigma fp.

If you decide to go through the ARRI Rec709 LUT, than you should consider using the fp in the bluely highlighted ISO range to get the rolloff.