This article has been moved to my new website timeinpixels.com dedicated to filmmaking.
You can access it here:
http://timeinpixels.com/2015/02/understanding-bmpcc-exposure-zebras/
Sorry for the inconvenience.
http://timeinpixels.com/2015/02/understanding-bmpcc-exposure-zebras/
Sorry for the inconvenience.
Thank you for this very informative! So for Raw Shooting I got it, then about prores film mode I just need to set the Iso but that will not affect the highlights, so for no clipping I need to adjust the exposure, right?
For ProRes Film mode the everything is the same as for RAW, except the ISO setting is “burned in” to the video file, and we cannot go back to native 800.
So if you are in ProRes film mode just check zebras at 100% for clipping, and you are good to go. The ISO setting will just make your final image brighter or darker, but will not affect the clipping (if it’s not showing 100% zebras at ISO 200, it won’t clip even at ISO 1600).
I must be missing something I see the histograms suggesting clipping in all the shots were clipping was occurring. What did I miss?
This is because histogram is based on the displayed image, not the image that is being recorded. In the screenshots I’m recording in “film” mode, and display is set to “video” mode. So the histogram is showing that the “video” mode is clipped, while sensor records perfectly fine image in film mode.
This is why I mentioned that histogram cannot be trusted for the exposure judgement. Hope it’s clearer now.
I would set the bmpcc zebras at 90%-95%, instead of 100%
There has been discussion on some of the boards about the bmpcc zebras “averaging” the three color channels. So, with the zebras set at 100%, the “average” of the three color channels might not show clipping, while one or two of the channels could actually be clipped — with no indication from the zebras.
Hi Joe, thanks for your comment. This is very interesting. It has never happened to me, and I was shooting loads of footage with zebras set to 100%, maybe this happens in a specific situation — I was trying to clip pure reds and blues, but didn’t manage to. Will have a closer look and will try to reproduce the problem myself.
Hi, first off: great blog you’re writing! Thanks!
Secondly: I’m wondering if, when you set the zebra’s to 100% and ETTR, with RAW there are still one or more extra stops to recover highlights right? How much would this be? Haven’t had the time to test this, but maybe you have?
Ah, I’m sorry, I now see this: “100% Zebras = sensor clipping (regardless of any settings)”. I really thought there was still some wiggle room there…
Yes, I wouldn’t rely on highlight recovery. There might be “some” room, but in vast majority cases when the zebras are visible at 100% the details and color information are gone. And thanks for the nice words – glad to hear that it was useful for you!
Great article, it improve the image a lot! Now I use this method of exposing!
Awesome! Glad it was helpful for you!