Does the C300 suffer chroma clipping?

[Rick Burnett]

The Alexa does the cyan shift as well, just not as bad. The way I found this out was I watch the show Fringe and happened to notice cyan around the lights in one of the labs in the show. I was like, wow, that's strange. So I head over to IMDB curious to see what they shot with and I see they switched on the season I was watching to an Arri Alexa. The fact I noticed the highlights changed in the show VERY easily was VERY interesting to me.

The problem is, when you get these situations is that what you are wanting to do is ramp all 3 colors to max if ANY of the 3 colors approaches max. I started a plugin for this for AE/PPRO but the problem I was having is the compression being used ruins the edges between hl color shifts and dark edges. 4:2:0 especially. It's basically desaturating the highlights.

In studying the 7D this is what Canon seems to do on the DSLR.

I've not used the C300 enough to know what the codec is like, but if it is 4:2:2 then it should be MUCH EASIER to fix this. Although the problem some area dealing with on the rainbow edge, that is not as easy to fix, although there is one pretty good solution if needed earlier in the thread.

 

[cowpunk52]

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.

Welcome to the world of digital cinema - this is how things work. If you use a cine gamma or c-log, you're going to have a harsher roll off to white. The camera is hanging on to every bit of highlight information it possibly can to maximize dynamic range. When you're shooting in these gammas, it's imperative to keep watch keep your exposure in check. Any of the NORM gammas have a far smoother roll-off, but you will pay for it with the loss of a little DR.