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Juan Melara

P6K to ARRI Alexa - Resolve PowerGrade

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Why can't you use Highlight Recovery with Alexa footage? I shoot ML Raw with a 5D3 and use Highlight Recovery in the Raw Tab. I assume it's because I'm interpreting the CDNGs as BM Film or Rec709? But if that's the case, couldn't you just transfer the Alexa footage to CDNGs, interpret as BM Film and then do a CST to LogC, with Luminance Mapping, and also use Highlight Recovery to utilize the full range + of LogC?

Btw, I'll often use the WB presets to tweak any issues, or just to get uniformity between clips and it defaults to 10 Tint... should I be turning that to 0? As Shot, my tint is usually a little less than 10.

Anyway, cool product. How does your PowerGrade handle shots that the Alexa would excel at, but the P4K/P6K would struggle with?

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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
9 hours ago, heart0less said:

That's a great news.

I think the original X-T3 is highly underrated camera, but seeing how X-T4 is welcomed, it may no longer be the case in the upcoming months. Luckily, both of them, apart from sharing the same sensor, seem to have the same color science.

They don't offer RAW, unfortunately, but 10-bit @400Mbps is still plenty of data for color manipulation. 

I'm in for the X-T3/X-T4 to Alexa Powergrade. Would love to have it.

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10 hours ago, mercer said:

Why can't you use Highlight Recovery with Alexa footage? I shoot ML Raw with a 5D3 and use Highlight Recovery in the Raw Tab. I assume it's because I'm interpreting the CDNGs as BM Film or Rec709? But if that's the case, couldn't you just transfer the Alexa footage to CDNGs, interpret as BM Film and then do a CST to LogC, with Luminance Mapping, and also use Highlight Recovery to utilize the full range + of LogC?

Btw, I'll often use the WB presets to tweak any issues, or just to get uniformity between clips and it defaults to 10 Tint... should I be turning that to 0? As Shot, my tint is usually a little less than 10.

Anyway, cool product. How does your PowerGrade handle shots that the Alexa would excel at, but the P4K/P6K would struggle with?

I would say it's because the Alexa is already doing highlight recovery as part of it's dual gain architecture. ARRIRAW or Prores recording, It's on by default.

You can set to tint to whatever makes your image look good. 0 is just the suggested value as that creates the most neutral response across the entire luminance range for most scenarios.

Apart from general colour, the two main areas the Alexa excels at is dynamic range and handling mixed temperature or off temp light sources. The PowerGrade can't change dynamic range so it doesn't help there. But the way you expose on set and the ISO you rate the camera, can close the gap. For mixed temp sources, as long as you are prepared to adjust the white balance and tint, you can get pretty close.

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Pocket series is not approved by Netflix... how dare you to compare it with Alexa? LOL ; ) Pure vapour, the merest hoax! LMAO : P

E : -)

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great work with the conversion @Juan Melara I am going to purchase it both powergrade and lut.

based on your extensive tests matching the cameras, did you notice a noticeable difference between 4k and 6k in terms of DR and especially in exposure recovery? I ask because in this test there is a massive recovery gap in favor of the 6k:

4k recovery test    //    6k recovery test

thx in advance.

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1 hour ago, pantxu said:

great work with the conversion @Juan Melara I am going to purchase it both powergrade and lut.

based on your extensive tests matching the cameras, did you notice a noticeable difference between 4k and 6k in terms of DR and especially in exposure recovery? I ask because in this test there is a massive recovery gap in favor of the 6k:

4k recovery test    //    6k recovery test

thx in advance.

 

Beyond charts, I didn't put them side by side. But in real world testing the difference in highlight range is hard to notice in most situations.

At ISO800 theres 6.5 stops above middle gray for the P4K, 6.9 on the P6K, 7.8 on the Alexa. On charts the differences are easy to see. In the real world with correct exposure anything above about 6-7 stops is into extreme highlight territory, which doesn't actually occur often in outdoor scenes. In all the P4K/Alexa sample images in this post it's only the lights in the dusk shot that are beyond 7 stops. So for most shots the extra ~0.4 stop is hard to notice. Where it would be noticeable is if you place anything important up in that range and try and bring it back, like those tests you linked to.

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1 hour ago, Juan Melara said:
 

Beyond charts, I didn't put them side by side. But in real world testing the difference in highlight range is hard to notice in most situations.

At ISO800 theres 6.5 stops above middle gray for the P4K, 6.9 on the P6K, 7.8 on the Alexa. On charts the differences are easy to see. In the real world with correct exposure anything above about 6-7 stops is into extreme highlight territory, which doesn't actually occur often in outdoor scenes. In all the P4K/Alexa sample images in this post it's only the lights in the dusk shot that are beyond 7 stops. So for most shots the extra ~0.4 stop is hard to notice. Where it would be noticeable is if you place anything important up in that range and try and bring it back, like those tests you linked to.

If you ever get around to doing the Ursa mini I'd be interested how many stops above middle grey it has. 

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19 minutes ago, thebrothersthre3 said:

If you ever get around to doing the Ursa mini I'd be interested how many stops above middle grey it has. 

https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=101735

+5.9 according to Black Magic.

Which is still pretty darned good. With raw recovery this could surpass the F5/F55 (+6 but noisy shadows so worse in practice), EVA1 (+6), and C300 Mk II (+6.3) and surpass most Reds, too.

The pocket 6k is a pretty amazing camera btw. But it feels noisier at 800 ISO to me than the Alexa or the Ursa. 

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5 minutes ago, HockeyFan12 said:

https://forum.blackmagicdesign.com/viewtopic.php?f=2&t=101735

+5.9 according to Black Magic.

Which is still pretty darned good. With raw recovery this could surpass the F5/F55 (+6 but noisy shadows so worse in practice), EVA1 (+6), and C300 Mk II (+6.3) and surpass most Reds, too.

The pocket 6k is a pretty amazing camera btw. But it feels noisier at 800 ISO to me than the Alexa or the Ursa. 

That would mean the Pocket 4k out performs it in highlight retention? 

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5 minutes ago, thebrothersthre3 said:

That would mean the Pocket 4k out performs it in highlight retention? 

At 800 ISO I'd guess so. But the Ursa seems a lot cleaner to me. I'm guessing the P4K and P6K are more like 400 ISO cameras that still look okay at 800 ISO and the Ursa is more like an 800 ISO camera. I bet the URSA Mini still has the most overall dynamic range and you could always expose at 1600 ISO. 

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59 minutes ago, HockeyFan12 said:

At 800 ISO I'd guess so. But the Ursa seems a lot cleaner to me. I'm guessing the P4K and P6K are more like 400 ISO cameras that still look okay at 800 ISO and the Ursa is more like an 800 ISO camera. I bet the URSA Mini still has the most overall dynamic range and you could always expose at 1600 ISO. 

Interesting, the tests I've seen against the pocket 4k indicate more dynamic range, I thought 800 was native on the Ursa. 

I should test my URSA against the 4k and 6k my friends have. 

I was pretty pleased with it today shooting against a window, completely backlit. I tried underexposing to retain more highlight detail as well as exposing for the face. Turned out it looked the best when I just exposed for the face to begin with, highlight recovery was able to take care of the blown out parts. 

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31 minutes ago, thebrothersthre3 said:

Interesting, the tests I've seen against the pocket 4k indicate more dynamic range, I thought 800 was native on the Ursa. 

I should test my URSA against the 4k and 6k my friends have. 

I was pretty pleased with it today shooting against a window, completely backlit. I tried underexposing to retain more highlight detail as well as exposing for the face. Turned out it looked the best when I just exposed for the face to begin with, highlight recovery was able to take care of the blown out parts. 

I might have misspoken. I think the Ursa is 800 native, the impression I get from the Pocket 6K is it's more like a 400 ISO camera that you can push a stop. So when you push it a stop you get an extra stop of highlight detail compared with the Ursa, but the Ursa seems cleaner in the shadows to me if you rate both at 800 ISO. I don't think any of those numbers factor in raw recovery, which other raw formats (Arri raw, canon raw light, etc.) usually don't support.

I have relatively little experience with either camera. Both seem to have very good dynamic range to me.

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Amazing job as always, Juan. I learned a great deal about color grading from you.

 

I'd love to see an X-T3 version! Instant purchase for me.

 

Cheers

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On 3/3/2020 at 10:34 PM, Juan Melara said:

You can set to tint to whatever makes your image look good. 0 is just the suggested value as that creates the most neutral response across the entire luminance range for most scenarios.

Interesting, I wonder why Tint defaults at 10 with the WB presets in the Raw Panel. It makes sense that it should be set to 0 for neutrality though. 

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3 hours ago, mercer said:

Interesting, I wonder why Tint defaults at 10 with the WB presets in the Raw Panel. It makes sense that it should be set to 0 for neutrality though. 

This is based on common colour science used by Adobe and many others. If you look at Adobe presets in camera RAW, or the Resolve WB presets you will notice the same thing. Daylight is typically green compared to a black body radiator (tungsten) and the daylight locus is used for temperatures above 4000K.

Here's the daylight locus compared to the Planckian (tungsten/black body radiator). Notice it's "greener" and therefore would need a tint adjustment towards magenta to compensate
Daylight-locus-in-CIE-1960-UCS.png

More info here:
https://en.wikipedia.org/wiki/Standard_illuminant
https://en.wikipedia.org/wiki/Planckian_locus

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