Question about clipping/exposure control BMPCC

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Hi all - apologies in advance for what will probably be super-newb questions. I have a lot of years of colour-correction and post work for print, but zero experience and training for film/video. I'm learning on the fly so I can better support some one of the charities that I volunteer with. Your patience is appreciated.

My question: learning how to expose/grade with the BMPCC and Resolve. I did a bunch of test footage in ProresHQ (current SD cards can't record to RAW). I know the exposure was slightly clipped in the brightest highlights because I don't have an ND filter yet. Shot at f22, so the image quality is also poor. Shot in Film Mode with a Panasonic 14mm 2.8

The question I have: looking at the files in Resolve it I can see the clipping in the waveform, but it looks like everything is clipped around 800, not 1024. Looking at the curve editor, I see the brighter highlights seem to live on the shoulder of the curve where I would typically expect to see 3/4 tones (in print), and not up at the top which appears to be empty. It's like everything is compressed into 0-800 and there doesn't seem to be much to expand out.

Even discounting the clipped areas I am not seeing a crazy amount of tonal range in the highlight areas - not what I had hoped to see with the BMPCC anyway. I'm wondering if I'm missing something, or does this appear normal? Should I just be shooting RAW to avoid this?

Thanks for any advice.

Brett Simms

Same here.
I tried to save the grade, take out the footage and import again in the timeline and it seems to be good again. But sooner I remade some adjustments, the higlights clips again.

(current SD cards can't record to RAW)

I do believe your best option here is to solve that.

I'm not clear on what's actually being asked here, or if the first two posts are asking the same question, but 100% levels, as indicated by BMPCC zebras or the histogram for log footage will fall at 1023 on the Resolve waveform. If the camera was set to an ISO lower than 800, highlights will clip well below maximums on the waveform, dropping about 10% for each halving of ISO. At a setting of ISO 200, 100% would fall to about 800 on the waveform. This is a good reason to leave the ISO setting at 800, when shooting log.

Raw is unlikely to make any difference, beyond turning the ISO into metadata, so the ISO settings won't permanently alter the footage the way they do with log.