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GH5 to Alexa Conversion


Sage
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59 minutes ago, JeremyDulac said:

Cant wait! Is it close to ready??

The hard part is done; its comfortably a slam dunk, so to speak.

Here's a taste - this is HLG (converted to VLog) and VLog (HLG is on bottom, with equally increased saturation to demo color, and overlayed vectorscopes):

5ab510544618b_HLGvVLog.thumb.JPG.de395343fa93ba53aefc027b11461dc7.JPG

The waveforms are likewise identical, and the conversion is silk, throughout the entire color space.

5ab51269147b8_HLGvVLog-Waveforms.thumb.JPG.fac10ea3ce343519a328d3de57c46147.JPG

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EOSHD Pro Color 5 for Sony cameras EOSHD Z LOG for Nikon CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs

I've been working on it since December; a custom coded color engine that accepts ~25,000 samples per camera, and smoothly interpolates between all of them.

For a sense of perspective, GHa v1 was clocked at ~1000 samples per camera, and the average Lut has ~36k points - allotted to the entire *potential RGB range

I'd like to do something for the 4k temp range; what light model do you use?

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1 hour ago, Sage said:

I've been working on it since December; a custom coded color engine that accepts ~25,000 samples per camera, and smoothly interpolates between all of them.

For a sense of perspective, GHa v1 was clocked at ~1000 samples per camera, and the average Lut has ~36k points - allotted to the entire *potential RGB range

I'd like to do something for the 4k temp range; what light model do you use?

Results look great!

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@ Sage.  I have remote phosphor based lights by BB&S and Cineo. They both license the same patented phosphor formulation, so quality of the light is the same at the same panel color temperature. I have 5600k, 4300k and 3200k panels.

I am planning using them together to give me a color temperature between 4300k-4400k: 4300k (single 4300k panel),  4400k (combination of 5600k and 3200k) and 4350k (combination of 4300k/5600k/3200k).  I should have said I have tri-color lights, but that would have taken some explaining... ;  )

I would be happy to shoot some test charts. I have a ColorChecker Passport and I can purchase the additional color charts as you require.

Thanks!

Mark

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Hi Sage,

Will you be offering the GH5s conversion as a free update? I have the GH5 but may sell it to get the GH5s as it would suit my needs more. But I want to get into shooting something as it looks great and also test it out.
Will the color coded engine be an app that you input the Kelvin into to get the lut? 

Sounds intriguing!

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Yes - send an email to emotivecolor (at) gmail indicating you'd like to use it with the GH5S.

That's one of the things I'm considering. The tricky part is that there could be endless 4300ks, because every light will be seen differently by the sensors (which becomes more important when the new standard point is reference grade). An active software would have different lights to choose from, and accept chart inputs to anchor the conversion

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I followed your instructions in the pdf using Resolve 14  )) 

making sure the luma are within the range of 128 - 768 we get the desired Alexa look. 

If I use Log- C I should be able to make any colour corrections needed but should I stray away from those luma levels or would that defeat the purpose of using the Lut?

 

window gold.jpg

US shoppers.jpg

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Just bought this and decided to try it out after a day out in the sun, accompanied by my son and a cheap variable ND filter.

I shot slow-motion in V-Log, 4K24p in HLG, and when I switched modes to shoot some stills, I forgot to switch back to HLG and later realized I had been shooting half of my video clips in the Like 709 profile.

When it was time to learn the workflow of these LUTs, I tried using the Joo.works GH5 colour correction kit (which turns a few of the other profiles like CineD into V-Log) to prepare the wrong clips, and to my surprise it actually looked pretty good - especially considering the conversion was from Like 709, which wasn't right at all.

Disclaimer: My colour vision is not the best, but this might be useful if you have some old CineD footage you have laying around that you need to spice up! Although I hopefull won't make the same mistake again ;)

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11 hours ago, dxotic said:

I followed your instructions in the pdf using Resolve 14  )) 

making sure the luma are within the range of 128 - 768 we get the desired Alexa look. 

If I use Log- C I should be able to make any colour corrections needed but should I stray away from those luma levels or would that defeat the purpose of using the Lut?

The luma range guidance is really for those using VLog encoded to Prores; otherwise the native VLog should be read correctly. For grading the final shot, the noise floor should most often be placed lower than 128. 'Main' will place luma levels optimally for a wide dynamic range shot. I intend to add a luma grading addition to the Pdf. Its good that you're using Resolve; that is the recommended NLE for GHa at the moment (update for PPro soon). Those are pretty intriguing shots by the way

@iplaythebongos Ah, that kind of thing will happen : ) There is a degree of universality to Main/Soft

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Just want to say the LUTs are great. It's interesting how different GHa is from the GHaLogC-ARRIAlexaLogCRec709 pairing.

Thoughts on a more neutral LUT with basically just the highlight rolloff (no longer having oversaturated and color shifted highlight transition is wonderful), or should I just use the Leeming LUT?

One note for anyone else using Resolve on a non-cinema wide-gamut hardware-LUT display (not specific to this conversion at all, just in general for color grading): Accurate color absolutely requires the usage of a flat system ICC profile, a monitor-loaded LUT, and a 3D LUT in Resolve (3D Color Viewer LUT) as Resolve does not appear to be ICC aware in any way, shape, or form. This isn't particularly noticeable with SOOC footage, but Log footage run through a LUT (let alone complete color grading) is pretty painful otherwise.

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On 3/26/2018 at 8:16 PM, Sage said:

The luma range guidance is really for those using VLog encoded to Prores; otherwise the native VLog should be read correctly. For grading the final shot, the noise floor should most often be placed lower than 128. 'Main' will place luma levels optimally for a wide dynamic range shot. I intend to add a luma grading addition to the Pdf.

 

 Those are pretty intriguing shots by the way

Great! looking forward to the luma grading pdf. you can send me an advance copy if you like ;)

 

Just walking around and shooting what i see in varying light sources to see how the LUT behaves 

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