Does the C300 suffer chroma clipping?

Bern Caughey

Bern Caughey

Veteran
Sorry if this has been covered elsewhere.

One of the features I'm hoping for most out of a C300 is an absence of chroma clipping in the highlights, & a soft/smooth rolloff to white. Hopefully at least as good as the 5D2's, & 7D's.

I haven't had a chance to test the camera yet, & would appreciate any feedback beforehand.

Thanks,
Bern
 
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The moire thread? I read it earlier, even participated, but didn't find this question answered.

I''m particularly interested in chroma clipping on skin.

Thanks,
Bern
 
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Bern the answer is No, it doesnt. This camera rolls of chroma nicely, so when one channel clips for example its clamped to let the others catch up.
 
Noel Evans said:
Bern the answer is No, it doesnt. This camera rolls of chroma nicely, so when one channel clips for example its clamped to let the others catch up.
Click to expand...

Can you explain how this works? Because it sound different than what I found on say the 7D/5D.

When one channel clips on the 7D, as it reaches clip, the other two channels ramp up so they all hit clip at the same time.

The reason I know this is that if I film say an LED with a very tight spectral distribution (ie, no blue or green or VERY slight) when I overexpose, the color goes white, yet, I know there isn't any blue/green to get to white like it is. That's how I discovered what they were doing different on other cameras where I don't like the HL roll-off.
 
Not sure if this is related at all. I shoot with the RGB waveform and switch constantly between that and audio levels. And I use zebras at 100%.

What I don't like is that my red channel can clip, ruining skin tones, but the zebras don't show. I guess it's because the green & blue channels aren't clipping. But I think that if any one of the three channels is clipping, then I should get zebras.
 
Maybe I'm using the wrong terminology. I'm pretty sure it is normal behavior for the different color channels to clip (overexpose) at different times depending on the white balance and color of the subject and light.

My complaint is that my 100IRE zebras don't come on when the red channel clips. I have a shoot tomorrow, I can probably replicate it and get pics of the LCD.
 
Bern. I should qualify my post a little. Under real world working samples I have not seen any evidence of it at all. Actually I haven't seen it period on anything I've shot.
 
I tried to blow out the skin at noon-sun....the camera does´t suffer from blooming like the HVX and others.
It is no problem to pull back the highlights and add saturation to the LOG-clip.
Shot in C-LOG.
 

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My complaint is that my 100IRE zebras don't come on when the red channel clips. I have a shoot tomorrow, I can probably replicate it and get pics of the LCD.[/QUOTE]
Well, yeah, that's right - zebras won't do that. Zebras show the combined calculated brightness, but not the color channel levels. Brightness is (ballpark) 60% green, 30% red, and 10% blue. Want to blow your mind? Shoot an absolutely pure blue light, and expose it at full maximum brightness, 100% full saturation, and then look at the levels in your waveform or on your zebras: it'll show about 11 or 12 IRE, max.

Zebras and waveform don't show you when a color channel clips. You'd need a different tool for that.
 
Guys - the camera works amazingly. I'm the one who originally started the post on the rainbow-like moire pattern that was the result of some artifact that I believe Canon technicians are now looking into. It isn't the result of typical moire issues, it's not chromatic aberration either, and that post expanded into another conversation altogether than what I was seeing.

As for skin tones and rolloff, Bern, you're gonna love this camera. LOVE IT. :-)
 
Not sure if these images will be of any use whatsoever - but I had 5 minutes.
TOp is original.

MEI.jpg
CCMEI.jpg
BWMEI.jpg
 
Thanks for the input Barry. To me it would make sense for zebras to show even if only one channel is clipping. But hey I'll just keep an eye on my RGB parade. Coming from the EX1 a couple years ago, I thought it was perfect to have the handgrip button on the C300 toggle magnification. But then I realized I would actually need it to toggle waveform/audio leves so I can keep an eye on both. And with peaking, I am comfortable shooting without magnification. But does anyone know if you can disable the vector scope? It would be nice to press the button only once to go from the waveform to audio levels.
 
So it´s my first post here finally. I´m from germany and i shot a music video as DP and two other projects as Assistant Camera with the C300 for now.
And going back to Bern´s question, i must say, unfortunately the C300 does NOT have the most pleasing highlight roll off. So far for my experience and taste. As Bern said, it also was my biggest hope for the camera, despite dynamic range and resolution.

The problem for me is, it still looks very harsh and videoish when it comes near to clipping. This has nothing to do with dynamic range or handling exposure, it´s the roll off to white.
For example (i hope someone understands my clumsy english :) when you have a blue sky and you overexpose it near to 100 IRE, it gets that cyan color cast before clipping, far from that nice rendering like Arri Alexa and even Sony F3 s-log. Of course not as ulgy as Panasonic HVX, but EOS 5D looks better in the highlights i think (again, not the dynamic range thing).

I´m a bit disappointed from that, because it affects the overall quite pleasing image and definitely doesn´t look very film like. I dealed with it in DEsaturating the highlights in post and making some curve adjustments, but I´m no pro in post stuff
By the way, the 'EOS' color matrix in custom picture profiles gets you the nicest highlight roll off (better than c-log).


I suggest to watch the Alexa vs. C300 test on vimeo.
https://vimeo.com/39338528

Go to 3:18 when she comes from outside and look at the wall getting cyan.
Go to 7:39 and look at the skintones getting yellow.
 
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