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GH5 to Alexa Conversion


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The V4 email should be out to everyone; if you haven't received it please let me know. A month ago, my father was diagnosed with advanced colon cancer at the same time that the virus situation was taking off, and life was thrown into disarray. March is colon cancer awareness month, and we are aware now (get screened every 10 years, starting at 50)

The GH5S is, at last, supported. V4:

 

Emotive Color Component ('EC709')

- Remade in 'HDR', preserving intense values (exceeding 0.0-1.0), that are incorporated into final Rec709 envelope

- Using the new engine, Arri Rec709 primaries are recreated at lower saturation, while 'projecting' this primary behavior to HDR gamut extents (beyond Arri Rec709 gamut clipping)

- Raised highlight ceiling for Main (average between Soft and Linear)

- Significantly refined saturation envelope for Main and Linear (& Soft, to a lesser extent)

 

Core LogC

- Remade with new engine (Incorporates initial baseline HSL conform)

- Fixed chart scan error that added 1/18th incorrect neighboring sample value to each sample average (hidden mistake in my very earliest code)

   (Corrects for persistent slight inaccuracies despite multipass, such as magenta bias of shadow skin tone in Tungsten)

- Fully linearized highlight rolloff (true to LogC) with maximal detail retention (effective highlight DR increase)

- New smoothing algorithm (incorporated into engine) - 12 passes, combining two hue-aware algorithms for new smoothness standard while preserving hue lines

- Most extreme gamut is now directly measured and preserved (i.e. colored Leds in night environments)

 

Misc.

- Added Exposure Compensation [PRE]s - actual exposure color conversions for use ahead of the conversion (interpolated from sample data, incorporating rolloff)

- Added Auto Black Level POSTs - for use following the conversion; quickly conform black level in any NLE 

   (No accompanying relative hue/saturation distortion whatsoever, unlike standard luma tools)

- Remade all PREs with new engine, taking new NLE measurements to accommodate NLE profile rendition shifts since original release

- Direct monitoring variations included for HLG and Cine-D, and VLog external monitoring variation (includes levels fix)

- Rewrite of Pdf (for Gen.4)

- Direct FCPX support added (with distinct PREs and Pdf)

- Significantly more efficient file sizes

- 16 bit Gradient Chart included to test smoothness of theoretical & far gamut, and reveal pipeline banding issues

- Each file is now unique to its owner at coordinate level

 

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Sure; it depends on what you'd like. Fuji and BMD have very good, usable color. I personally will use P4K with GH5; I hope to have EC to do a production this summer. 8 bit is tricky; I'd prefer t

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Emotive Color Version 3 Core LogC Details - Rewrote engine to work at 65x65x65, main files are now at eight times resolution (supporting files processed at that resolution) - Fine tuned mu

Posted Images

13 hours ago, Sage said:

The V4 email should be out to everyone; if you haven't received it please let me know. A month ago, my father was diagnosed with advanced colon cancer at the same time that the virus situation was taking off, and life was thrown into disarray. March is colon cancer awareness month, and we are aware now (get screened every 10 years, starting at 50)

The GH5S is, at last, supported. V4:

 

 

Really sorry to hear about that @Sage Thanks for all the work you do on this, it's much appreciated, although events lately and your personal news put all this camera stuff into perspective. Take care mate.

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18 hours ago, Sage said:

The V4 email should be out to everyone; if you haven't received it please let me know. A month ago, my father was diagnosed with advanced colon cancer at the same time that the virus situation was taking off, and life was thrown into disarray. March is colon cancer awareness month, and we are aware now (get screened every 10 years, starting at 50)

The GH5S is, at last, supported. V4:

 

Emotive Color Component ('EC709')

 

Much blessings to papa Mack! Thats much more important. Dont care if there is delays with the updates. Fam is much more important

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On 4/15/2020 at 12:27 PM, Sage said:

They look good guys -

The BT 709 step shouldn't be needed in theory - one can conform FLog directly to VLog, and then apply the conversion, followed by ABL/luma to add contrast. The red, cyan, and yellow look really nice together

*By the way, how do you like V4 (and the new Pres/Posts) so far?

Really sorry to hear about your father. I'll be sending my positive energy from here. Take your time and focus on what's most important!

 

V4 is really good to use, and the new exposure pres and ABL posts are definitely the final touch to an amazing package you put together with Emotive Color. 

 

About the BT709 LUT, I can't seem to find FLog color space in the Color Space Transform, only the FLog gamma seems to be there, that's why I decided to try out the BT709 lut and leaving Rec709 as the input color space.

 

Take care!

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I hope your father can defeat the cancer @Sage. I have experienced a similar situation with my father (throat cancer) one year ago...they had to cut his vocal chords (translation from google) and now his voice is something like the Donald Duck...but he is fine and he was not a singer or something that needs his voice...so we are very happy and we hope that cancer never appears again (this is the most important thing).

Anyway...congrats four your good job on the gh5 alexa conversion, surely I will try it in the future (now, with all my currents and future jobs cancelled and with no idea of when I could work again, I should not spend money but only on what is necessary). 

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  • 5 weeks later...

I know it hasn't been designed for that but I'm currently editing a little BTS and accidentally slapped GHAlex on some GoPro footage and.. it actually looks quite good. Of course there's some artifacting and stuff but it looks a lot better than standard protune.

Big shot is GoPro, small shot is GH5 shooting CineD. Same adjustment layer on both clips.

Main.00_02_52_06.Still005.thumb.jpg.5681f2c99c0b009a352ee4b13473e45f.jpg

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  • 4 weeks later...
On 6/13/2020 at 9:13 PM, mirekti said:

Is there anyone using v4 LUT with S1H? I wondered if it could be used at all given the fact GH5 is using v-log lite.
If so, could someone share few hints what one would need to do to make it work with S1H, please? 

I haven't used the S1 myself; I believe that @austinchimp and @Parker use it with the S1 specifically. I 'd like to support the S1 directly eventually, though there are some hefty items I'm working on at the present moment. With V4 specifically, the standard is now to project 'edge' behavior of a color space infinitely into theoretical values beyond 0-1 (resulting in clean theoretical values beyond the target color space). This means that if a V4 conversion is used on unintended display formats, they will be handled as if they were an extension of that core transform at center, free of artifacts (unlike V3). The entirety of S1 gamut and DR are addressed by the conversion, albeit not directly measured.

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5 minutes ago, Sage said:

I haven't used the S1 myself; I believe that @austinchimp and @Parker use it with the S1 specifically. I 'd like to support the S1 directly eventually, though there are some hefty items I'm working on at the present moment. With V4 specifically, the standard is now to project 'edge' behavior of a color space infinitely into theoretical values beyond 0-1 (resulting in clean theoretical values beyond the target color space). This means that if a V4 conversion is used on unintended display formats, they will be handled as if they were an extension of that core transform at center, free of artifacts (unlike V3). The entirety of S1 gamut and DR are addressed by the conversion, albeit not directly measured.

Translated in English, if one wanted to use v4 GH5 for S1H, should one expose the same, and then if there's some color case at which node should it be corrected? :)
Thanks!!!

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2 hours ago, Sage said:

I 'd like to support the S1 directly eventually, though there are some hefty items I'm working on at the present moment. 

Hoping you can figure it out.
Both the S1 and S1H look exactly the same color-wise. Same sensor, same gamut/gamma, the S1 is just a tad sharper because of the missing OLPF.

Would love to see a proper conversion for full V-Gamut, although the official V35 conversion is quite good already. 

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@mirekti Yep you shouldn't have a problem using the LUT on the S1H, @Sage is right, I use it all the time on the S1, it requires a little bit of tweaking, but can be made to match the reference gh5 very closely. There isn't any visual difference between the S1 and the S1H, same dual-iso, color space, and same full v-log profile. 

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17 hours ago, Sage said:

I haven't used the S1 myself; I believe that @austinchimp and @Parker use it with the S1 specifically. I 'd like to support the S1 directly eventually, though there are some hefty items I'm working on at the present moment. With V4 specifically, the standard is now to project 'edge' behavior of a color space infinitely into theoretical values beyond 0-1 (resulting in clean theoretical values beyond the target color space). This means that if a V4 conversion is used on unintended display formats, they will be handled as if they were an extension of that core transform at center, free of artifacts (unlike V3). The entirety of S1 gamut and DR are addressed by the conversion, albeit not directly measured.

Yes GHa works very well on my S1 and S1H files using Premiere. I haven't seen a real difference between the two cameras in terms of colour. If I were using Resolve I'd probably go with a color transform node and get it into Arri space or something, but I prefer Premiere so I just drop the Lut over my footage. Generally I need to reduce the exposure on the footage to get the Lut looking good.

I tried loading the monitoring LUT into the camera, but it looked awful - probably because the S1 is a different camera to the GH5 obviously.

I also tried the native Panasonic LUTs on the footage, but GHa looks a million times better. I like the Linear version personally, then grade from there.

Of course I'd love a proper S1 version of GHa too! I think that would be phenomenal... Looking forward to a monitoring lut that works with the S1

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