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Sage

GH5 to Alexa Conversion

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@Wild Ranger I think it looks great! And you shoot under the most challenging light conditions (would love to see that in VLog with a halogen bulb if you've got one on hand, just for kicks)

Can you post the VLog stills? I think the black level is good. For interiors/nights, blacks are best between 1-3 IRE (but never at 0 or below!)

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EOSHD Pro Color for Sony cameras EOSHD Pro LOG for Sony CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs
6 hours ago, Sage said:

I think it looks great! And you shoot under the most challenging light conditions (would love to see that in VLog with a halogen bulb if you've got one on hand, just for kicks)

Can you post the VLog stills? I think the black level is good. For interiors/nights, blacks are best between 1-3 IRE (but never at 0 or below!)

Hi sage, I shot all in CineD, i don't use vlog for a convenience matter. But i can share you raw stills of these clips.

If you what i can try shot something in tungsten lights for test and share it here.

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6 hours ago, Wild Ranger said:

Hi sage, I shot all in CineD, i don't use vlog for a convenience matter. But i can share you raw stills of these clips.

If you what i can try shot something in tungsten lights for test and share it here.

Sure! And that will help when I revisit Cine-D (I like to collect in-the-field images from everyone to act as a north star, they become part of the reference set)

And if you have true filament tungsten (i.e. halogen, rather than led/flo), that test would be great (in true VLog)

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Emotive Color "Verde"  V2.2 Release

EC Component:

  • Saturation Target Revision
  • L'Abbée 709 Hue Lock-In
  • Soft and Pop Luma Revision

Core LogC:

  • Multipass Refinement Technique (Maximal Accuracy; for example, accurate Tungsten far red)
  • New Smoothing Pass
  • Fixed Red Highlight Artifact (Bright Red Traffic Lights Hyper-Saturation)

Additional Notes:

  1. OLPF settings have been revised to take into account the larger sensor area of modern 3.2k/LF Alexas and real world GH5 footage testing
  2. Added guidance for optimal DaVinci Resolve luma grading tools; In the Color Wheels section, use the more organic Shadows/Highlights (under Tab 2) instead of LIft/Gain, which allow crushing of detail to 0 and 100 IRE, respectively. Contrast/Pivot (Tab 1) and the Gamma slider are safe tools (see attached Color Wheels image)
  3. Like in Premiere, the Resolve Luma curve also distorts hue. To address this (when using it for more than black level placement as in Pdf, i.e. 'curvy'), you can qualify the Luma curve node with a Layer Mixer *set to 'Hue' composite mode*, and an empty node ('hue passthrough') routed to the bottom slot of the Layer Mixer (Thanks to David L'Abbée for this discovery)
  4. Firecrest Full Spectrum NDs recommended for reference performance (better for GHa than IRNDs, such as Hoya Pro)
  5. PDF updated to reflect changes (Pages 3, 8, 9, and 10)
  6. Raw Footage Side-by-Sides updated to reflect Verde, with 16 bit Tif Stills Only versions added (much smaller download)
  7. All-I (2K or 4K) VLog recommended; Sunlight & Halogen recommended as reference light sources (for respective conversions)

 

Raw v2.2 Video:

(No color grading, black level placement, or post WB correction [Sunny WB preset in cam for day shots]; only the Main conversion directly on VLog)

*For Color Accuracy - Please watch in Microsoft Edge, Explorer, Safari, Chrome with the sRGB Dev fix, or Chrome (Mac Edition) - *Avoid Firefox! (Or download 'Original' file on Vimeo for total fidelity)

 

Verde.thumb.jpg.d4b5c5a5986a373234f674184165fe71.jpg

Best Resolve Luma Tools

333003773_BestResolveLumaTools.jpg.4355277d8635ed90fdd2f301e3ef4c1d.jpg

1497989343_HuePassthru.JPG.912d94f9d7666ffb00998809f0f2f483.JPG

 

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Can’t you do this conversion with davinci resolves color management in floating point precision ? A lut wouldn’t be nearly as accurate as it needs to be to convert to Alexa’s color science. LUTs are hardcoded by nature. Looks nice though

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2 minutes ago, kidzrevil said:

Can’t you do this conversion with davinci resolves color management in floating point precision ? A lut wouldn’t be nearly as accurate as it needs to be to convert to Alexa’s color science. LUTs are hardcoded by nature. Looks nice though

I don't think you realize how powerful luts actually can be. Davinci transforms don't account for sensor interpretations..just the data sheets that each manufacturer provides on their flavor of log profile. 

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@JeremyDulac I do. I make my own LUTs. LUTs do not compare to floating point operations, not by a long shot. Its the prime reason why ACES is 32 bit floating point instead of 64 x 64 x 64 high resolution LUT. 32 bits has WAY more transformations than even a 256 x 256 x 256 LUT. 

And this is why LUTs can color clip channels but the 32bit floating point transformations of Davinci wont. 

Also VLOG is a gamma & color space specification. You don’t need a LUT specific to each camera to convert VLOG if the program you are using has a manufacturer based transform that built for said color space & gamma specification

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Just now, kidzrevil said:

@JeremyDulac I do. I make my own LUTs. LUTs do not compare to floating point, not by a long shot. Its the prime reason why ACES is 32 bit floating point instead of 64 x 64 x 64 high resolution LUT. 32 bits has WAY more transformations than even a 256 x 256 x 256 LUT. 

 

I understand they are more powerful, but again they arent accounting for a lot of things baked into these luts within the ACES workflow. They don't account for correcting the flawed color science coming off the Gh5 sensor for example. That is a whole other thing aside from converting color spaces. And while luts arent as powerful, they can handle a lot more complex transformations than I ever realized. Not trying to say luts are better at all.

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???? Huh ? 

VLOG is a color space / gamma specification. You do not need a LUT built specifically for the GH5’s “color science” if the input transform was built for said color space & gamma. If that were true a LUT built for gh5 vlog wouldnt work on gh4 or gh5s. @JeremyDulac 

the only way a LUT has half the chance of doing a color space transformation to a HUGE color space like Alexa’s is with tetrahedral LUT interpolation and even that is a reach. 

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2 minutes ago, kidzrevil said:

???? Huh ? 

VLOG is a color space / gamma specification. You do not need a LUT built specifically for the GH5’s “color science” if the input transform was built for said color space & gamma. If that were true a LUT built for gh5 vlog wouldnt work on gh4 or gh5s. @JeremyDulac 

the only way a LUT has half the chance of doing a color space transformation to a HUGE color space like Alexa’s is with tetrahedral LUT interpolation and even that is a reach. 

Yes I would argue a lut built specific to the sensor of the Gh5 would perform differently on the GH5 than the GH4 for VLOG. Companies tweak their color science camera to camera to improve it. There are further conversions going on other than just color space transforms. This is why id guess that a company like say FilmConvert makes a new profile for every Sony camera even though they all have Slog2/SGamut...the color science is always slightly different sensor to sensor...

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Its not the color science thats different its the cameras sensor or color filter array that can “see” more colors than a lower quality sensor. A sensor from one camera could see more red than the other BUT since they are all using the same color space & gamma the results are always predictable and manageable. 

i.e. rec709 is 6 stops of DR whether its coming from a sony or a canon @JeremyDulac

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53 minutes ago, kidzrevil said:

Can’t you do this conversion with davinci resolves color management in floating point precision ? A lut wouldn’t be nearly as accurate as it needs to be to convert to Alexa’s color science. LUTs are hardcoded by nature. Looks nice though

Hey there! Just getting back from lunch. Resolve's color space conversion (and the other Lut color space calculators) do a conversion between the known parameters of the color spaces (in this case VLog to LogC). What this conversion does is incorporate all that comprises a color science output, by measuring the end result of each with ~25K color samples under a given light source, and interpolates between them with a color engine I wrote

Until the start of 2017, I felt exactly the same way. This thought experiment kept coming back to me over the years; if I shoot a scene under a given light source with a given camera, and then come back days later and shoot that same scene with that same camera, will the image differ? The revelation was that, it would be the same! It sounds silly, but this fundamental static color response revelation is what opened the door of possibility in my mind

*Here are some raw footage Side-by-Sides to play around with

Alexa LogC

Untitled_2.1.1.thumb.png.bb93ddef413f1091fb25f94d7dac4efe.png

GHa LogC (v2.2)

Untitled_1.1.1.thumb.png.d4b2248c10af6841f822e3a4a5f67e66.png

Original VLog

Untitled_1.1.2.thumb.png.7f52ce172b501ded169526f18c434deb.png

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6 hours ago, Sage said:

Sure! And that will help when I revisit Cine-D (I like to collect in-the-field images from everyone to act as a north star, they become part of the reference set)

And if you have true filament tungsten (i.e. halogen, rather than led/flo), that test would be great (in true VLog)

Here are the stills in Cine-D.

These are shot with Daylight balanced leds (around 5500K with a little shift of +3 to magenta). I have some tungsten bulbs around, I will share some stills with them as soon as I can make a test. 

1364728415_P1044369(01046).thumb.png.e385e0b2a527f6751904a70eb566e5b1.png877986279_P1044371(01249).thumb.png.aab8f5685905ce77709e78813eabe18e.png

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@Sage like I said earlier these look nice and no one can take that from you but this looks more like a hue, saturation, luminance adjustment to match the cameras. There is a lot more to a color space than an HSL and gamma/contrast adjustment. LOG C has a wider color gamut than VLOG L which would probably cause a lot of issues using certain LUTs designed for LOG C. This is more like a look LUT than a technical one but I guess I can’t make that assessment until I put them in my NLE

again these look nice but I don’t think its a true colorspace conversion. 

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3 minutes ago, Wild Ranger said:

Oh, i have a question!

Is this "Verde" new release supposed to replace the actual daylight or is only a different look?

All the files replace the previous ones

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