Llaasseerr

When I see the prices of how "high" a F35 still sells for on eBay, when they do rarely pop up, vs an OG ALEXA Classic (which keeps on sliding down in price, cheaper and cheaper), then I'd say the choice is very obvious: get the Alexa!

I have enough crap lying around that I can rig out a C200B. Def thinking about picking one up. It seems the sensor noise performance in the shadows is the Achilles heel in this DGO era, but considering it’s so much cheaper than a C70, one can maybe put up with a Neat Video pass. I’ve seen a bit of a nasty horizontal banding in the red channel for night footage, not too bad but it’s there. Maybe that person forgot to do the black balance which is apparently pretty essential with this camera.
I have the Sigma fp and would say the s35 crop image is cleaner. But the fp is far from user friendly compared to the c200. Both have their place.

Agreed! I went through a phase of wanting one, but I got talked down by an owner who said they loved it but moved on to an Alexa Classic.

I own the Classic. It definitely has the best image in the game in terms of color accuracy and dynamic range. It is also just an industry standard image wise, super hard to mess up in post.

I think the F35 has a more unique image though, almost film like. The Alexa does too but its a cleaner more neutral image. The F35 is also a bit less power hungry and a bit smaller, though possibly more awkward. 

Having simple 12 bit internal recording up to 60p and 120p 10 bit with no cropping is nice on the Alexa Classic though. No external recording required. 

I do think that there are times RAW Convertor (sp?) can be inaccurate, so it may be worth trying a demo and comparing to a Prores 4444 log export for accuracy. As far as grading experience and flexibility, there's no real difference between Prores Raw and DNG. 
Overall, if you export to Prores 4444 log, you will have the same experience as grading linear raw. You can get the same temperature, exposure and white balance controls with Resolve as the raw controls as long as you're correctly applying them.
 

I'm of the opinion that ProRes Raw quality is very good. Obviously it would be great if Sigma could apply lossless or lossy compression to the internal DNG recordings the same way BMD were able to pre-RED drama. It would also be great if Sigma could take a cue from Atomos about how they managed to implement log + LUT monitoring.

I must say I love this little camera. Especially since the LUTs are now workable. Have attached you a couple of pictures, am currently recreating a scene together with my wife and child. Guess some of you will recognize the movie? 🙂 
Lit by candles only. Lens used DZO Vespid 50mm at T2.1 and fp set to ISO 3200. 

Once it is ready I will post a link here as well so that you can judge the image quality. But do not expect great acting, we are both not even bad actors, more like no actors at all. 😄 
 

Unless there's an error in their matrix transform, the "intermediate gamut" metadata tag being added into the raw stream by the Ninja V already displays the raw image in Vgamut. So under the hood it's already transforming from Sigma RAW gamut to Vgamut. So then all you need to do is apply the single Vlog/Vgamut to Rec709 LUT on the Ninja V.
The two step transform is only an issue in FCPX. It's possible that the gamut transform LUT in FCPX is incorrect because it was supplied by Panasonic for their cameras. Having said that, I realize now that the S5 has the same sensor as the fp, so it's not too bad a choice for Atomos to co-opt Panavision's color science as a workaround for the lack of an equivalent from Sigma.
If you suspect there may be an error on Atomos' part, what might be worth trying is using Play Pro to transform PRR to Vlog/Vgamut, then apply the standard Rec709 LUT. Then use the Ninja V as output from your computer via HDMI and seeing if it visually matches the way the Ninja displays the PRR clips.
 
 

I found something interesting yesterday. When you set the fp to output raw when you have a connected monitor over HDMI that is not the Ninja V, it displays the b+w mosaic sensor image. You can clearly see all the highlights and where they're clipping because it's underexposed. Obviously if you have a Ninja V connected, it can display the image as Vlog which is more clear, but I thought this was interesting.
 

I found something interesting yesterday. When you set the fp to output raw when you have a connected monitor over HDMI that is not the Ninja V, it displays the b+w mosaic sensor image. You can clearly see all the highlights and where they're clipping because it's underexposed. Obviously if you have a Ninja V connected, it can display the image as Vlog which is more clear, but I thought this was interesting.
 

It is basically just metadata except for when it switches from base ISO of 100 to 3200. There is also a difference in DR between different ISOs because some of them are clipping the highlights at the same value even as they raise middle grey. I also noticed there seems to be some good subtle in-camera work taming the noise floor with, for example, ISO 800 vs if you shot ISO 100 and boosted by +3 stops.
From my tests with DNG, it's clear to see the advantage of ISO 3200 over ISO 800 when it comes to an improved noise floor, at the expense of about 2/3 stop less highlights. I would need to double check the behavior with the Ninja V though. It is nowhere near as dramatic as the higher base ISO in something like a Sony a7sIII/FX3/FX6 though.
Here's an example using 12-bit DNG. On the left is shadow detail at ISO 3200 and on the right is ISO 800, both exposed for middle grey -2 stops (to protect more highlights) with the Sigma kit lens which is very contrasty. I'm pushing the exposure up in the extreme so you can see how the ISO 3200 is holding the color in the shadows, not clipping at black and also not contaminating with green.

What interests me about 3200 besides shooting in under lit scenes, is using it with wide contrast scenes if I underexpose it by 1-2 stops. So I can take advantage of the better noise floor while protecting highlights. Otherwise 800 (base ISO 100) is a good choice.
 
It's about setting a usable key/fill ratio. In an uncontrolled setup where you're not lighting from scratch it would be about ideally adding enough fill to keep shadows from being at zero and enough diffusion to tame extremely harsh bright light.
I don't see why that would be the case.
 
 
 

There's no rule that a LUT has to necessarily show sensor clipping at 100 IRE, especially at a low ISO. If you look at the linear clipping value at low ISO especially on the Ninja V which does not use highlight reconstruction, it's a very low value and gives the impression that the fp is bad with highlight detail.
So if you transform that low value to Vlog then apply a Vlog to Rec709 curve, I can't imagine it would get anywhere near 100 IRE, but it would also not be indicative of what is the native ISO.
Depending on how aggressive the highlight rolloff is on a log to 709 LUT, it can be hard for anything to get to 100 IRE so viewing in log might be a better way to measure max IRE from the sensor.
 

It is basically just metadata except for when it switches from base ISO of 100 to 3200. There is also a difference in DR between different ISOs because some of them are clipping the highlights at the same value even as they raise middle grey. I also noticed there seems to be some good subtle in-camera work taming the noise floor with, for example, ISO 800 vs if you shot ISO 100 and boosted by +3 stops.
From my tests with DNG, it's clear to see the advantage of ISO 3200 over ISO 800 when it comes to an improved noise floor, at the expense of about 2/3 stop less highlights. I would need to double check the behavior with the Ninja V though. It is nowhere near as dramatic as the higher base ISO in something like a Sony a7sIII/FX3/FX6 though.
Here's an example using 12-bit DNG. On the left is shadow detail at ISO 3200 and on the right is ISO 800, both exposed for middle grey -2 stops (to protect more highlights) with the Sigma kit lens which is very contrasty. I'm pushing the exposure up in the extreme so you can see how the ISO 3200 is holding the color in the shadows, not clipping at black and also not contaminating with green.

What interests me about 3200 besides shooting in under lit scenes, is using it with wide contrast scenes if I underexpose it by 1-2 stops. So I can take advantage of the better noise floor while protecting highlights. Otherwise 800 (base ISO 100) is a good choice.
 
It's about setting a usable key/fill ratio. In an uncontrolled setup where you're not lighting from scratch it would be about ideally adding enough fill to keep shadows from being at zero and enough diffusion to tame extremely harsh bright light.
I don't see why that would be the case.
 
 
 

@Llaasseerr I am now learning to use the camera in the V-log way (with and without a LUT).
What I simply do not understand is that if the camera records RAW data, ISO value is basically just metadata. That being said since the fp has dual iso it must have two native EIs. The DR of the camera is always the same no matter the ISO setting both native EIs. 
Have seen couple of videos explaining that in a dark environment you should use a low EI value and in bright a higher EI. They try to explain that with selecting different ISO values, you are just shifting the middle grey point.
On one hand it makes sense to let as much light into the camera in a dark environment as possible, and in a bright environment do the opposite. But yet I am not 100% sure I understand what they mean.
For the fp I have noticed that with false colors turned on (and the V-log LUT) only as from ISO 320 you are touching 100 IRE. So I assume that is in reality the native ISO value of the sensor. Or is that already wrong?
Maybe you are willing to explain so maybe I can understand this?

@OleB just an update on my early experience shooting with the Ninja V, monitoring as Vlog and with a correct LUT expecting Vlog and transforming to Rec709 works as expected, which is great and can replicate my timeline color at the start of a new Resolve project. In fact when I rewatched the Atomos setup video on Youtube, it even mentions on the screen that the "native" encoding is Vlog (in addition to the firmware release notes PDF you pointed out before), so it was staring me in the face before but I missed it.
So that's the good news. The bad news is like you said, it's also been awkward in my early testing to get exposure with a light meter. Despite all my ranting about how I don't really like false colors and IRE and whatnot, it is totally legitimate to expose middle grey at around 42 IRE on the waveform when displaying as Vlog as a sanity check for the light meter reading. But so far I haven't got middle grey to hit 42 IRE when exposing as per the light meter. This is easy to do with other cameras I've used. I did try with the underlying ISO that you suggested (either 100 or 640) and will do a few more tests to get to the bottom of whatever weirdness is going on there. Possibly I just made a stupid mistake. 
What would be really great is if Sigma did a firmware update that allowed you to monitor with the Ninja V in Vlog, but record DNG raw internally or to the SSD. Currently it's either/or. Because obviously through the Ninja V we get all the highlights visible. Basically it adds the log monitoring capability that Sigma did not add. ProRes Raw is a good option though, but for example as opposed to DNG I don't think you get any highlight recovery.

@OleB I atted you for my last post but it wasn't highlighted, so you may not have seen it. I was having issues exposing, but I realized I made an error with my ND filter. All good now. I was able to expose 3200 by setting the light meter for 640. Thanks for your detective work.
Seems to work fairly well with getting middle grey at close to 42 IRE on the Vlog display on the Ninja, then I can flick on a viewing LUT. I could also do it directly through the LUT. I just need to confirm in Resolve where middle grey falls on the waveform.

I'm actually picking it up today! I'll probably be super lazy about getting around to learning it and shooting with it, but hopefully I'll post a few tests here eventually. Thanks for all the help from people here willing to post test footage.

This clipping point is in line with the characteristics of the PRR test clips you uploaded before, and broadly speaking, also the behaviour of the DNGs, so I don't see anything strange here. We established that up to ISO 800 was an amplification of the base ISO 100 signal so the clipping point is raised accordingly. As the signal increases it should also be raising the noise floor obviously, but we noticed that the noise floor stays pretty low which is a nice win. 
For whatever reason, this taps out above ISO 800, so there are diminishing returns as far as overall dynamic range. When a camera is baking in the ISO change, the clipping point would ideally continue to increase. Maybe Sigma prioritized a clean noise floor instead of highlights for the higher ISO ranges (>800).
So using ISO 800 is a decent option. Regarding ISO 3200, the higher base ISO, it has a lower clipping point but my observation is that it has a proportionally lower noise floor. So my recommendation for absolute max DR was to shoot 3200 at least -1 stop underexposed since you could raise the noise floor and it would be the same as ISO 800/1600, but with additional highlight headroom. If you think about it, this is in line with the expected behavior with higher base ISOs: lower noise floor and slightly lower highlight clipping point. I understand this is a bit of a headache to track for a marginal gain, so shooting ISO 800 is a good rule of thumb to get max DR to keep things simple.
 
 
Well again, the IRE value is LUT or view gamma-dependent, but your numbers make sense. The base ISO 100 has a lower clipping point than ISO 800 which is baking in an amplification of the signal, but somehow also keeping a similar noise floor.
For example with this ISO 800 test clip, when importing as V-log into ACES and viewed through the standard ACES output display transform the clipping point is in the high 90's so it stands to reason that ISO 100 would clip lower.

 
 
 

OK there you go. So yes it's confirmed that Atomos decided "Native" = Vlog. After you said it, I googled it and found the AtomOS release notes update PDF that you're quoting from. This certainly reduces a lot of uncertainty. It's a shame the Atomos rep was not able to clarify this when I emailed them a while ago.
The Vlog curve spec defines 8 stops above middle grey, so the max linear value is 46.0855. (0.18*2*2*2*2*2*2*2*2). The fp sensor clips way before the max value that Vlog was designed to hold so it should not be an issue. Based on the test clip you recently uploaded with the sun clipping out of the window, it's clipping at about 0.833 in Vlog so that would be like 83 IRE. In scene reflectance terms once converted from Vlog to linear in Nuke, that's 9.36. So it's clipping more than 2 stops below the Vlog max value.
This screengrab illustrates where that is in relation to the entire scene reflectance range defined by the Vlog curve. Specifically this shows a Vlog to linear transform, so it's the inverse of a Vlog curve.
At the bottom, the input numbers represent the equivalent of an "IRE value" (0.83) and the output numbers represent the scene linear value (about 9.4, matches Nuke). So as you can see, there's a ton of headroom remaining that will never get used.

 
 
That means on the same Vlog to linear transform the input is about 0.59 and the output is 0.9. Here's a screengrab showing you how much extra headroom you get for capturing highlights above that. You basically get all of the curve to the right of the green arrow I drew.

 
So while it's not ideal that Sigma don't have their own log curve, Vlog is okay as a monitoring option on the Ninja V.
It doesn't matter what ISO you use, you will never use up all of Vlog. This is assuming there's no funny business going on where the Atomos is somehow clipping the highlights as they come in from the camera, but I doubt that.
Just to clarify, it doesn't matter which monitoring option you choose on the Ninja V, the underlying file is exactly the same. The difference between monitoring in PQ or V-log is that Vlog requires you add your own LUT, while PQ out of box creates a "display" image that takes advantage of the extra nits of the Ninja V but it's just a consumer HDR display standard for TVs.
So if you want to view the same image while shooting as in your timeline, you would match the display settings in both the Ninja V and FCPX, which is all you do in any software/hardware combo anyway. All that's been figured out is that the "Native" input is a known log format (Vlog), so that means it's easy to figure out how to load the look from your editing/grading software into the Ninja V. 
 
 
 
 

This clipping point is in line with the characteristics of the PRR test clips you uploaded before, and broadly speaking, also the behaviour of the DNGs, so I don't see anything strange here. We established that up to ISO 800 was an amplification of the base ISO 100 signal so the clipping point is raised accordingly. As the signal increases it should also be raising the noise floor obviously, but we noticed that the noise floor stays pretty low which is a nice win. 
For whatever reason, this taps out above ISO 800, so there are diminishing returns as far as overall dynamic range. When a camera is baking in the ISO change, the clipping point would ideally continue to increase. Maybe Sigma prioritized a clean noise floor instead of highlights for the higher ISO ranges (>800).
So using ISO 800 is a decent option. Regarding ISO 3200, the higher base ISO, it has a lower clipping point but my observation is that it has a proportionally lower noise floor. So my recommendation for absolute max DR was to shoot 3200 at least -1 stop underexposed since you could raise the noise floor and it would be the same as ISO 800/1600, but with additional highlight headroom. If you think about it, this is in line with the expected behavior with higher base ISOs: lower noise floor and slightly lower highlight clipping point. I understand this is a bit of a headache to track for a marginal gain, so shooting ISO 800 is a good rule of thumb to get max DR to keep things simple.
 
 
Well again, the IRE value is LUT or view gamma-dependent, but your numbers make sense. The base ISO 100 has a lower clipping point than ISO 800 which is baking in an amplification of the signal, but somehow also keeping a similar noise floor.
For example with this ISO 800 test clip, when importing as V-log into ACES and viewed through the standard ACES output display transform the clipping point is in the high 90's so it stands to reason that ISO 100 would clip lower.

 
 
 

OK there you go. So yes it's confirmed that Atomos decided "Native" = Vlog. After you said it, I googled it and found the AtomOS release notes update PDF that you're quoting from. This certainly reduces a lot of uncertainty. It's a shame the Atomos rep was not able to clarify this when I emailed them a while ago.
The Vlog curve spec defines 8 stops above middle grey, so the max linear value is 46.0855. (0.18*2*2*2*2*2*2*2*2). The fp sensor clips way before the max value that Vlog was designed to hold so it should not be an issue. Based on the test clip you recently uploaded with the sun clipping out of the window, it's clipping at about 0.833 in Vlog so that would be like 83 IRE. In scene reflectance terms once converted from Vlog to linear in Nuke, that's 9.36. So it's clipping more than 2 stops below the Vlog max value.
This screengrab illustrates where that is in relation to the entire scene reflectance range defined by the Vlog curve. Specifically this shows a Vlog to linear transform, so it's the inverse of a Vlog curve.
At the bottom, the input numbers represent the equivalent of an "IRE value" (0.83) and the output numbers represent the scene linear value (about 9.4, matches Nuke). So as you can see, there's a ton of headroom remaining that will never get used.

 
 
That means on the same Vlog to linear transform the input is about 0.59 and the output is 0.9. Here's a screengrab showing you how much extra headroom you get for capturing highlights above that. You basically get all of the curve to the right of the green arrow I drew.

 
So while it's not ideal that Sigma don't have their own log curve, Vlog is okay as a monitoring option on the Ninja V.
It doesn't matter what ISO you use, you will never use up all of Vlog. This is assuming there's no funny business going on where the Atomos is somehow clipping the highlights as they come in from the camera, but I doubt that.
Just to clarify, it doesn't matter which monitoring option you choose on the Ninja V, the underlying file is exactly the same. The difference between monitoring in PQ or V-log is that Vlog requires you add your own LUT, while PQ out of box creates a "display" image that takes advantage of the extra nits of the Ninja V but it's just a consumer HDR display standard for TVs.
So if you want to view the same image while shooting as in your timeline, you would match the display settings in both the Ninja V and FCPX, which is all you do in any software/hardware combo anyway. All that's been figured out is that the "Native" input is a known log format (Vlog), so that means it's easy to figure out how to load the look from your editing/grading software into the Ninja V. 
 
 
 
 

Have investigated this further.
Look what I have found in regards to the fp behavior in RAW on the Atomos.
Monitoring of RAW input in:
- Native – Linear to VLog for use with 3D LUTs – can use any existing VLog LOOK LUTs
- Rec709 – to view RAW input in SDR up to 6.7 stops of dynamic range
- HLG – to view RAW in HLG with up 10.5 stops of dynamic range
- PQ – to view RAW in PQ/HDR10 with up to 10.5 stops of dynamic range, for scenes with extended spectral highlights.
Am about 99% sure that the camera is showing Vlog when switched to native.
As far as I understand from the Vlog white paper 90% reflection is located at about 60 IRE, on ISO 100 the fp clips at about 62 IRE. The higher you go with the ISO (up to ISO 800). The more headroom on top is available.
That seems to match the design of Vlog. Panasonic itself writes that Vlog was build to capture the DR of the Varicam, cameras like the GH5 can use the same Vlog but will clip below 100 IRE because of the less DR available.
That means you can use the cameras in one shoot and mix them with the same Vlog look. Have also read that Blackmagic took another approach and always create a log for each camera to use the best DR available.
So yes, it seems that you can get a quite good match with the Vlog and the official Panasonic Vlog Rec709 as LUT on the monitor.
However I am not too sure if this is at least for me a good way of working since I do not know if the next step would be now to figure out the native ISO of the camera for maximum DR in Vlog? S1 or S5 seem to have dual ISO as well with possibly the same sensor, but min ISO would be 640...Cannot imagine that with the fp you can set it to ISO 100 and get good results with Vlog? Or am I getting something wrong now?
For now I prefer the manual colorspace matching in FCPX directly from the untouched linear RAW, which gives me great results. And with the PQ view in the monitor I can get a really good idea on how the picture will look like.

Thanks for the clip, by way of comparison I rendered it within a basic color managed setup. In this case I decided to ingest the PRR file in Play Pro to V-log/Vgamut based on the included metadata tags. This is assuming that maybe the Ninja V image is just V-log (unconfirmed), so that would create monitoring consistency with the Ninja V.
Since I took this into an ACES-managed imaging pipeline, it would not have really mattered if I exported as Alexa LogC, since I would just use the appropriate input transform for the log/gamut encoding into the common ACES space.
First I have the ACES default rendering for sRGB (good for web viewing). This is just a film print-like transform that is parametrically generated as opposed to being fixed like a LUT, so it's able to account for the output device. Basically, it's similar to an Arri to Rec709 LUT except it's adjustable on the fly for the output device.
If the Ninja V is really showing a V-log image, then you could apply a "V-log to ACES to Rec709" LUT to get the same appearance while shooting.

 
Next I pulled down the exposure by -2 stops so you can see how the output transform handles the rolloff when there are more distinct transitions visible. The underlying exposure transform is on the linear floating point file, and the final look is just a view transform:

 
Now I disabled the output transform so you can see the linear file. This is probably the sort of thing people see in FCPX with no transform applied when they first import their PRR footage, with all the info clipped:

 
This is the same image with -2 stops exposure change so you can see that the highlight detail is in fact there, but it was not in viewing range and with no rolloff to look the way we want:

https://community.acescentral.com/t/luts-that-emulate-the-aces-workflow/1334
These were conveniently made available to download, so you would select the V-log LUT. They offer both full (data) range and legal (video) range versions depending on your device. I have a feeling the Ninja V is legal range, so if you use a full range LUT it will look too crunchy and contrasty.
There are "normal" contrast versions which is the default look, which is what I would use if wanting to match the default image when importing into an ACES project in Resolve. There is also a more low contrast version, but I would ignore that since to me, the aim it to get a matching image to Resolve.
You could also throw this LUT on PRR footage transformed to V-log in FCPX and although it would not be a true ACES project, you could see if the footage matches on the Ninja and on your Mac. Also, you have the option of trying the legal vs extended versions of the LUT in case there's a mismatch in how FCPX and the Ninja work. What I mean is, I don't know if internally FCPX works "full" range or "legal" range, or if there's the option to change that like there is on a per-clip basis in Resolve.
It might actually be worth just exporting your timeline to Resolve to grade there 😉
 

Thanks for the clip, by way of comparison I rendered it within a basic color managed setup. In this case I decided to ingest the PRR file in Play Pro to V-log/Vgamut based on the included metadata tags. This is assuming that maybe the Ninja V image is just V-log (unconfirmed), so that would create monitoring consistency with the Ninja V.
Since I took this into an ACES-managed imaging pipeline, it would not have really mattered if I exported as Alexa LogC, since I would just use the appropriate input transform for the log/gamut encoding into the common ACES space.
First I have the ACES default rendering for sRGB (good for web viewing). This is just a film print-like transform that is parametrically generated as opposed to being fixed like a LUT, so it's able to account for the output device. Basically, it's similar to an Arri to Rec709 LUT except it's adjustable on the fly for the output device.
If the Ninja V is really showing a V-log image, then you could apply a "V-log to ACES to Rec709" LUT to get the same appearance while shooting.

 
Next I pulled down the exposure by -2 stops so you can see how the output transform handles the rolloff when there are more distinct transitions visible. The underlying exposure transform is on the linear floating point file, and the final look is just a view transform:

 
Now I disabled the output transform so you can see the linear file. This is probably the sort of thing people see in FCPX with no transform applied when they first import their PRR footage, with all the info clipped:

 
This is the same image with -2 stops exposure change so you can see that the highlight detail is in fact there, but it was not in viewing range and with no rolloff to look the way we want: