SIGMA FP with ProRes RAW and BRAW !

[radar24]

On 5/5/2022 at 2:36 AM, Ryan Earl said:

I'm not too familiar with ACES, I've just tried these project settings and all the highlights seem available, lift gamma gain tools are responding great, color seems good:

How would you suggest setting it up for ARRI log C?

Is this the recommended setting for ACES setting? my resolve 17.4.6 doesn't show "apply ACES reference gamut compress" checkbox though. I've been using P3 D60 Linear Raw tab to CST input to output Arri LogC since i recently bought fp. It seems like ACES workflow is whole another thing that I gotta learn about it.. 

I think i need to get more accurate monitoring. relying on internal LCD is not easy and fun for me.. are Ninja and VA the only options? I will keep using cDNG so I don't need BRAW or ProRes Raw recording abilities. using one of them would be so much better for accurate monitoring? I like the form factor of EVF but the price is at the same level with those monitors and using EVF also means I still rely on the internal LCD and i feel it wouldn't do any improvement on accuracy. having external monitor on fp was not an option I would think of when getting fp.. I thought I would be fine with the internal LCD from my experience with bmpcc og with loupe.    

[Owlgreen]

I got the FP working with the Ursa viewfinder. I used a BMD microconverter and a 4-pin XLR to barrel cable, and then a barrel to usb-c 12V Power Delivery cable, connected to a powerbank with a 12V PD output. The microconverter can't be connected to the same powerbank, I don't know why. Some loop I guess. So it needs it's own powerbank. I'm still waiting on an FP cage, but testbench-style it all works. It won't be light, but the picture in the EVF is stunning. I swear the lag is better than I remember it to be on the UMP4.6K Gen 1. As in, basically no lag. That bit surprised me. 

[Ryan Earl]

7 hours ago, kye said:

It's also worth stating that many heavy colour grades will completely obliterate any sense of colour accuracy so I would imagine the pursuit of it is really only relevant in situations where a natural or hyper-natural (eg, commercial look where everything has to be cleaner than real life) look is required

My point I think as it pertains to the thread, is that the ‘off’ profile is the only option when recording out hdmi to braw.  So that’s where I initially noticed the color difference, doing dng and braw but I didn’t have ‘off’ set initially in camera for dng.

It’s a great sensor / camera without a ‘known’ or tried and true workflow.

[Ryan Earl]

10 hours ago, hyalinejim said:

I haven't been following this topic very closely and don't have an FP so disregard this if it's not relevant or has been covered already. I can tell you from much experience of looking at colour charts that the colours in "OFF" are far more accurate and true to life than in "ON". The blue patch is a giveaway here as it often is when a colour gamut or matrix is being interpreted incorrectly: in the "ON" version that patch is too purple.

Yeah, the blue patch might be too purple in the "on" image.  The other way I was looking at it, going along with how to interpret the DNGs in Resolve REC709 or BMD Film Gamma etc. was to compare it to the original Ursa Mini 4.6K DNG with Color Science 3.  I was thinking that I would be using mostly BRAW with the Sigma FP in studio but now have found my way back to DNG.

I posted my example in another thread, but I'll repost here.  Keep in mind both images have the same WB and Tint settings in the RAW tab.  If I decode Ursa Mini 4.6K Color Science Gen 3 with Blackmagic color and gamma, in DaVinci YRGB REC709 Gamma 2.4 I get the following:

URSA Mini 4.6K ISO 800 WB 5194 TINT 13.79

Then Sigma FP I transformed to REC709 with the CST method from Linear to get this:

Sigma FP ISO 800 WB 5194 TINT 13.79

Interesting that the Tint and WB can be set to the same values.  Though in the earlier examples just comparing ON & OFF, Sigma FP was set to "DAYLIGHT" in camera then in Resolve's RAW tab there were too different values for the "AS SHOT" WB & TINT.  The "on" setting seemed to be around 6500K and the "OFF" around 5600K.

Then you'll get the "off" color if you put the "on" DNG into BMD color and gamma so it gets even more confusing.

I can upload these DNGs too and their 'off' DNG counterpart that was taken at the same time if anyone wants to play around.  

What I was having trouble with is getting the violet spray bottle and the red disk to be the color 'as seen' and 'as in' the URSA 4.6K since that is my 'known' workflow for product work.  As I tried to move the bottle from blue to violet I would throw off everything and have to make too many selective adjustments where in the 'on' file all the color relationships were more intact.  So if the blue patch in the color chart was too violet for example in the 'on' DNG than a simpler global adjustment will work without throwing off the spray bottle or the red disk.  

Again, I don't think the color is ruined in either 'on' or 'off' but does the "off" profile have less color available? Does it restrict the gamut when you turn the color "off"?

[Llaasseerr]

10 hours ago, hyalinejim said:

I haven't been following this topic very closely and don't have an FP so disregard this if it's not relevant or has been covered already. I can tell you from much experience of looking at colour charts that the colours in "OFF" are far more accurate and true to life than in "ON". The blue patch is a giveaway here as it often is when a colour gamut or matrix is being interpreted incorrectly: in the "ON" version that patch is too purple.

Thanks for the reality check there. I've attached the "OFF" image imported through ACES with the sRGB output transform applied for web viewing, and it is more neutral in its rendition of the Macbeth chart.

Note: the exposure isn't quite matching this time, but you get the point.

I haven't been able to extensively compare DNG to the internal mov recording when both are set to OFF since I also don't own the camera. But from some comparison images posted a while ago, I was able to get the internal mov and the DNG matching closely by just doing an inverse Rec709 transform on the internal mov. The colors did look slightly desaturated, but that might have been perceptual because the other profiles just have more pop.

 

[webrunner5]

Put a Coke Cola can in that scene. Everyone knows what Red looks like with it as a reference. You have to have the 3 primary colors represented.

[TomTheDP]

@Ryan Earl

If you isolate the color chart and check the vectorscope which is more accurate?

 

[Llaasseerr]

Here's a version of OFF through ACES with a Rec709 target that may not be right for web viewing, but it can be compared a little more easily to what @Ryan Earl is posting. I also did a minor adjustment to exposure based on setting the grey chip closer to 0.18 in the RGB channels.

[Llaasseerr]

This image shows how an idealised colorchecker chart looks rendered through ACES AP0 with a Rec709 display target.

 

[Ryan Earl]

8 hours ago, webrunner5 said:

Put a Coke Cola can in that scene. Everyone knows what Red looks like with it as a reference. You have to have the 3 primary colors represented.

But do they? LOL

I attached two more DNG files to check out if anyone is interested with lots of commercial objects including some coke cans.   

Color "On" with a Kodak Film LUT. 

[hyalinejim]

7 hours ago, Llaasseerr said:

This image shows how an idealised colorchecker chart looks rendered through ACES AP0 with a Rec709 display target.

 

That's pretty cool, how was that chart generated? I find it hard to figure out sometimes how a Colorchecker should be represented by a given camera. Here the rendering looks a bit low contrast and darker than it should be. Patch D4 is just above 18% grey in reality so should be represented by at least 126, 126, 126 RGB in Rec709. And the brightest patch is 90% reflectance so it should be considerably brighter than shown here.

This is what the spectral data provided by X-Rite looks like in a linear gamma, converted to sRGB:

But of course a camera recording of this would be in a different gamma. Nevertheless, I always feel that D4 should be at whatever the middle grey values of the colour space is. Here's a photo of a Colorchecker using Adobe Standard picture profile:

D4 patch is the same but highlights are lower (there's a highlight roll off rather than clipping at 100% reflectance which you would get in scene linear) and the shadows are darker.

All this is to say that be wary of digital representations of colour charts for video applications. The spectral data file provided by X Rite is useful for calibrating the linear colour response of RAW camera profiles, but there are gamma issues to consider when matching actual shots to representations of charts: the gamma of the camera may not (and perhaps should not) match the gamma of the generated chart.

In this case, if somebody can get the different flavours of DNG into a scene linear gamma with no highlight recovery then the middle image above is what the visual reference should be for testing which flavour has the more accurate colour

[webrunner5]

1 hour ago, Ryan Earl said:

But do they? LOL

I attached two more DNG files to check out if anyone is interested with lots of commercial objects including some coke cans.   

Color "On" with a Kodak Film LUT. 

That looks pretty close to reality I think, maybe a Little bit on the lighter side but I think that is the best so far. But keep in mind I think everyone sees color a bit different and some people are just plain color blind.

They say women see color different than men do. They distinguish pastels better for one thing. Sure aren't going to argue with them that is for sure.

[PannySVHS]

Darn, one should write a guide with the knowledged written in your posts @kye @Llaasseerr @hyalinejim. Simpler to dig through for people like me. 🙂

[Ryan Earl]

2 hours ago, PannySVHS said:

Darn, one should write a guide with the knowledged written in your posts @kye @Llaasseerr @hyalinejim. Simpler to dig through for people like me. 🙂

Yeah, very good info.  

 

13 hours ago, webrunner5 said:

That looks pretty close to reality I think, maybe a Little bit on the lighter side but I think that is the best so far. But keep in mind I think everyone sees color a bit different and some people are just plain color blind.

It's kind of a vintage look with the saturation pushed down with the Kodak LUT for all of the consumables in the scene.

 

I forgot to paste the link to the DNGs in the previous post: https://we.tl/t-KABtBkd3OT

This is how it looks with Adobe Color in Photoshop Camera Raw without any adjustments besides the default 'adobe color.'  It's using the opposite window as a light source and I have the camera set to 'daylight.'  

 

[webrunner5]

That one looks great. I think you have got it figured out.

[TomTheDP]

3 hours ago, webrunner5 said:

That one looks great. I think you have got it figured out.

yeah but adobe color is not really an option in NLE's unless you want to process in lightroom first.

[hyalinejim]

5 hours ago, Ryan Earl said:

Adobe Color in Photoshop Camera Raw

In my experience the Adobe profiles (Color, Standard and Neutral - they are basically 3 different contrast levels of the same profile) are quite accurate in terms of colour for all the cameras I've looked at.

If colour accuracy is the goal in Resolve then the Adobe rendering will give a good indication of what to look out for.

But of course many people (myself included) think that accurate colour is not necessarily the most pleasing colour.

[TomTheDP]

1 hour ago, hyalinejim said:

In my experience the Adobe profiles (Color, Standard and Neutral - they are basically 3 different contrast levels of the same profile) are quite accurate in terms of colour for all the cameras I've looked at.

If colour accuracy is the goal in Resolve then the Adobe rendering will give a good indication of what to look out for.

But of course many people (myself included) think that accurate colour is not necessarily the most pleasing colour.

Yeah I suppose if it renders accurate color in lightroom it should in general. 

The ARRI Alexa has very accurate color, but I think having accurate color under all lighting conditions and mixed lighting conditions is what really makes for more pleasing rendering. Very few cameras can do that.

[mercer]

I may be completely wrong here, but it seems like a lot of people are overthinking the workflow of this camera... from exposure to color... I don't know if it should be this problematic. Perhaps I am so used to workarounds with my 5D3 and ML Raw, so I don't understand the issues. But it shouldn't be this difficult. 

[TomTheDP]

48 minutes ago, mercer said:

I may be completely wrong here, but it seems like a lot of people are overthinking the workflow of this camera... from exposure to color... I don't know if it should be this problematic. Perhaps I am so used to workarounds with my 5D3 and ML Raw, so I don't understand the issues. But it shouldn't be this difficult. 

Just trying to find the ideal color workflow. I am sure for the majority of people this is pointless discussion.