Author Topic: What causes incorrect white & black levels?  (Read 530 times)

TequilaKez

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What causes incorrect white & black levels?
« on: February 15, 2021, 03:26:17 PM »
Recently I shot a bunch of stuff with some lights, and exposed both by 'eyeballing' the LCD and checking the histogram.
Bringing MLVs into MLVApp, everything looks really blown out. Highlights are obliterated.
Exporting as cDNG, I started to freak a bit when I realised I couldn't even recover the highlights in Resolve.

Back in MLVApp I discovered If I set the White Level to maximum, it looks roughly as it did on the LCD when shooting. I could rest a bit easier.
I've seen mention of these levels come up on the forum, but before switching from MLVFS to MLVApp, I've never had access to them, not had any need to.

So then,

A. How are these values set?
B. What should I investage if they are wrong? The camera? The ML version in use? or the software doing the conversion?
C. Is there anything wrong with selecting all the MLVs I just shot, and setting all their White Levels to maximum to try salvage my footage?

Sorry if this information exists somewhere on the forum, but I can't find it.

White Level according to MLVApp is set to 6000, but nothing looks even close to correct unless its set to somewhere in the 12,000 - 16,000 range.


EDIT: I can see now in some other posts that white level should be 16200 or even max 16383 for 5D Mk3. So why would it be set to 6000 in my files?



Danne

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Re: What causes incorrect white & black levels?
« Reply #1 on: February 15, 2021, 04:09:16 PM »
Because you probably used 12bit setting. Set it to 14bit and all should work with white level set to around 15000.

TequilaKez

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Re: What causes incorrect white & black levels?
« Reply #2 on: February 16, 2021, 12:25:03 AM »
Ok thanks for that.

Do you mean 12bit setting in the camera? If so yes, but I have 120GB of footage shot like that now.

I used to use the 12bit lossless on my 70D as my go-to setting and I don't remember encountering any issues with exposure.

These new files were shot on 5D mk3 with your crop_rec_4k_mlv_snd firmware Could that be why?


Danne

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Re: What causes incorrect white & black levels?
« Reply #3 on: February 16, 2021, 07:17:10 AM »
Nothing wrong with your footage. 12 bit reduces white level in this build.
You can easily compare with 12bit in non crop rec presets.

If you want more help you need to post mlv samples.