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Blackmagic Pocket Cinema Camera 4K


Yurolov
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I dit another test with a simple domestic RGB led (hence the flickering) to show how the BMPCC4K reacts in the red channel, both in raw and prores. With other colors, when overexposed, there is a gentle roll-off, but in the red, it clips with a very harsh way, and a strange color shifting. There is also much more noise in the reds. 

 

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ISO 1250 is the WORST iso to choose to test the red clipping issue.    It is pulled 3200 iso, so even properly exposed it only has 2.3 stops of latitude above middle grey.  So of course the highlights will clip and look shitty.  ISO 1250 will be the number one noob trap on this camera.

Im more worried about the wide angle lens blurryness.  Yes, lenses have field curvature that is more aparent wide open and yes the Pocket 4k has a wider field of view that shows more of it, but that alone doesn't account for what the examples in that thread show.  It must be the sensor stack thickness also.  If stopping down to 2.8 doesnt resolve that issue then that is going to be a way bigger deal breaker than red clipping.

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Well, if you don't want to show the red clipping, by preventing it with your exposure, you can. It is not the purpose of this test. The purpose is to show how the camera reacts specifically in the red channel, by comparison with other colors (and the problem is still there at 3200 iso). And I find it problematic in some situations : a night street scene, with its many red car lights will cause many problems, with disturbing hyper saturated  red blotches all over your image (whereas the greens, the blue and the yellow react normally). You can bypass it if you shoot in raw, but it will affect the entire image if you shoot in prores. 

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25 minutes ago, Slothorp said:

Well, if you don't want to show the red clipping, by preventing it with your exposure, you can. It is not the purpose of this test. The purpose is to show how the camera reacts specifically in the red channel, by comparison with other colors (and the problem is still there at 3200 iso). And I find it problematic in some situations : a night street scene, with its many red car lights will cause many problems, with disturbing hyper saturated  red blotches all over your image (whereas the greens, the blue and the yellow react normally). You can bypass it if you shoot in raw, but it will affect the entire image if you shoot in prores. 

It will definitely be a problem if you ever shoot scenes with neon signs.

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4 hours ago, TILT said:

Did you set infinity focus on the Viltrox, that could be the issue. You need to turn the optical element inside to make sure infinity focus is correct. I have the Nikon Version and no problem on a Pana M43. Still waiting the BMPCC4k to try it on though. Maybe the Viltrox covers the sensor a bit too much. Their factor is wrong it is not 0.72x but a little bit more.

Would you know if the Canon version works this way as well?

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3 hours ago, Slothorp said:

I dit another test with a simple domestic RGB led (hence the flickering) to show how the BMPCC4K reacts in the red channel, both in raw and prores. With other colors, when overexposed, there is a gentle roll-off, but in the red, it clips with a very harsh way, and a strange color shifting. There is also much more noise in the reds. 

 

Yeah I think I saw some night shots with the red lights on the cars clipping but didn't see the noise. On your test the sudden noise was quite distracting. Hope Blackmagic addresses this

Looks like the stronger red lights have a tendency to get clipped:

https://www.youtube.com/watch?v=54153YyAUVY

 

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I think the red clipping has beed adressed somewhat already.

43879064_10161009924555494_1990007718609

quoted, not my words.

"The overexposed super saturated LEDs are clipping the gamut. This will happen with Gen 4 on 4.6K too. You can reduce the issue by soft clipping the gamut using the colour space transform Resolve FX plugin. Here I am using the Broadcast gamut because the Pocket 4K option isn't in the colour space transform plugin at this time but they are actually the same gamut/primaries anyway."

 

Give it a shot, to see if it helps, this interests me as well.

Best regards

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4 minutes ago, jagnje said:

I think the red clipping has beed adressed somewhat already.

 

quoted, not my words.

"The overexposed super saturated LEDs are clipping the gamut. This will happen with Gen 4 on 4.6K too. You can reduce the issue by soft clipping the gamut using the colour space transform Resolve FX plugin. Here I am using the Broadcast gamut because the Pocket 4K option isn't in the colour space transform plugin at this time but they are actually the same gamut/primaries anyway."

 

Give it a shot, to see if it helps, this interests me as well.

Best regards

would be good to see a before and after.

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I have already tested this method. It works very well as far as you manipulate raw files. It desaturates the reds, providing some high light roll off without touching the rest of the image. 
But it is more difficult with prores files, because it can slightly desaturate not only the reds but also some other parts of the image, including skin tones. And it is worse with files recorded with a baked lut. 

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I have never used an Ursa, so I don't know, but I believe it's true, coming from Captain Hook own's words. Concerning the BMPCC4K, once you spot it one time, yo can see it in every night city scenes. Maybe you don't notice it on youtube, but on a big screen, it's very disturbing. 

Capture d’écran 2018-10-16 à 16.59.31.png

Capture d’écran 2018-10-16 à 16.59.55.png

 

6 minutes ago, Andrew Reid said:

Does it clip the blues as well?

No, the blues are much better handled. 

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4 hours ago, Slothorp said:

I dit another test with a simple domestic RGB led (hence the flickering) to show how the BMPCC4K reacts in the red channel, both in raw and prores. With other colors, when overexposed, there is a gentle roll-off, but in the red, it clips with a very harsh way, and a strange color shifting. There is also much more noise in the reds. 

 

Could you please upload few DNG from the video above?

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