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Sage

Pocket 4K to Alexa Conversion

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7 hours ago, Sage said:

However, I've found the sweet spot for streaming video sites is 2560x1440 (or 2560 pixels wide).

export.thumb.PNG.5309cd1262b7b73d02c7be167f3b4152.PNG

2.5K looks bad on 4K screens though, lots of smear and macro blocking especially on YouTube - and you can still select streaming quality manually. ;)

38 minutes ago, docmoore said:

Dump Safari in the Mac ... Firefox has better quality and color sense for video ... does not shift the gamma when you view things on the U or V.

Or chrome which can be color managed in chrome via about:flags url: Force color profile

Select sRGB (standard screens) or DCI-P3 (Mac and OLED) to enable color transform.


Still a bit pink as Alex already mentioned.

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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
1 hour ago, deezid said:

2.5K looks bad on 4K screens though, lots of smear and macro blocking especially on YouTube - and you can still select streaming quality manually. ;)

Or chrome which can be color managed in chrome via about:flags url: Force color profile

Select sRGB (standard screens) or DCI-P3 (Mac and OLED) to enable color transform.


Still a bit pink as Alex already mentioned.

Righto, I like to force 2.5K for motion and load speed. But I know you're a 4K guy :)

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1 hour ago, GeorgeN said:

will this work with the UMP G2?

 

Sage already answered that.

 

On 12/10/2019 at 4:21 AM, Sage said:
On 12/10/2019 at 3:10 AM, crevice said:

Alex - would I be able to use the pocket 4K version on the URSA mini pro, if I used a color space transform to get to the pocket 4K first. Or does that not make any sense? I’m very eager to see how good URSA mini footage would look with this. 

That could be done; granted it wouldn't be tailored to the sensor. I'd like to support it directly, and I think there may be some rental options that would make that feasible.

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On 12/28/2019 at 2:13 AM, jackch2n said:

After.thumb.jpg.0406778cec80b8b50605c090e28d6cf6.jpg

Pre Exp -0.66 + P4Ka Daylight Main + ABL 3

Very nice. Soon to put this one on the website -

159330629_P4KaTungstenMain(Final).thumb.png.b917e304d2ea632e0aaef5edd7f4d2fb.png

On 12/28/2019 at 4:48 AM, persol said:

I really want this all for my XT3. I hope to see that one day. ?

That's the plan. Today I finished a major engine rewrite, to greatly accelerate supporting new cameras. Its the most ambitious work yet, that self calibrates and auto iterates. It was enormously difficult, and I discovered legacy code mistakes dating back to the very beginning.

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1 hour ago, Sage said:

Very nice. Soon to put this one on the website -

159330629_P4KaTungstenMain(Final).thumb.png.b917e304d2ea632e0aaef5edd7f4d2fb.png

That's the plan. Today I finished a major engine rewrite, to greatly accelerate supporting new cameras. Its the most ambitious work yet, that self calibrates and auto iterates. It was enormously difficult, and I discovered legacy code mistakes dating back to the very beginning.

Sounds fantastic.

Cannot wait to see your work for the S1(H) also. :)

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2 hours ago, Sage said:

Very nice. Soon to put this one on the website -

159330629_P4KaTungstenMain(Final).thumb.png.b917e304d2ea632e0aaef5edd7f4d2fb.png

That's the plan. Today I finished a major engine rewrite, to greatly accelerate supporting new cameras. Its the most ambitious work yet, that self calibrates and auto iterates. It was enormously difficult, and I discovered legacy code mistakes dating back to the very beginning.

Thanks Alex! That's great to hear.

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10 hours ago, seku said:

Give us old GH5 users some v4 love as well ?

Working on it as we speak :)

18 hours ago, deezid said:

Sounds fantastic.

Cannot wait to see your work for the S1(H) also. :)

Its really neat; now I think several new cameras are achievable (in 2020). Days have been compressed to minutes

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1 hour ago, Sage said:

Working on it as we speak :)

Its really neat; now I think several new cameras are achievable (in 2020). Days have been compressed to minutes

Would this test and the accompanying RAW files help with your project?

https://cinematography.net/CineRant/2018/07/30/personal-comments-on-the-2018-cml-camera-evaluations/

https://www.myairbridge.com/en/#!/folder/XDn2Yx7xLBAaLh0Zbq415jcXW5hOa9SM

It seems that only Alexa can render pure red colour accurately, while others all skew towards orange, is this something that's specifically addressed in your colour engine?

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56 minutes ago, androidlad said:

Would this test and the accompanying RAW files help with your project?

https://cinematography.net/CineRant/2018/07/30/personal-comments-on-the-2018-cml-camera-evaluations/

https://www.myairbridge.com/en/#!/folder/XDn2Yx7xLBAaLh0Zbq415jcXW5hOa9SM

It seems that only Alexa can render pure red colour accurately, while others all skew towards orange, is this something that's specifically addressed in your colour engine?

I think he posted some code screenshot in the past where he fixed hue twists. I'm 99% sure he fixes this issue but I'll let the man talk :)

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Happy New Year!

Alexa has a distinctive red (when LogC is paired up with the intended display primaries). It is a deep magenta red, and twists moreso approaching extreme saturation. This can look stunning. Other cameras may opt for the default of twisting towards orange with increasing saturation because Cmos red clips to yellow, and the gamut clipping is more coherent. For example, the Alexa has an especially messy extreme red clipping at tungsten WB. With Gen 4, this extreme red behavior is simulated. Here is P4Ka v Alexa in extreme gamut, with EC709 (P4K at bottom):

249520706_ExtremeGamut-P4KavAlexa_2.1.1.thumb.png.77beecf108239a68f3ae97fd9fb6ee7a.png

Apart from desired hue twists, like Arri display gamut, hue twists when conforming color spaces via interpolation (in log etc) have generally been one of the main challenges in developing EC (to keep the true clean hue lines as they should twist). At many stages, I've coded the engine to preserve clean hue lines. Hue is perceptually salient in color, and has a privileged place in the engine today (whereas once upon a time, it was just 'one of three' in the engine)

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Another tricky thing is the hand-off from the measured space under a given light source (sunlight or halogen) to extreme gamut simulation. This is because extreme saturation is only achievable with color light sources (i.e. red leds etc.). This amounts to two different 'perceived' color spaces from the same sensor.

The challenge is to preserve hue lines of the measured light source as they move into extreme gamut, while simulating the behavior of extreme gamut. Hence, extreme gamut cannot be an exact match - note the difference in cyan and yellow especially (though can be similar enough as to be perceptually equivalent)

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