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TERRIBLE static in BMCC footage


Germy1979
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Yep, this one had the noise in your clip, but if you look at the scope chart (before fiddling with it) the trees look underexposed (definitely not exposed to the right, as they say).

Screen+Shot+2013-08-11+at+8.47.11+PM.png

 

So that means it was brightened up in your workflow, which introduced the noise. If you rendered it as it was shot (which i did), in BMD Film, it looks quite dark (with no noise).  So i conclude that this noise was introduced by brightening. Here is a version with only slightly less brightening. You'll notice there is less noise. 

 

https://vimeo.com/72162002

 

I consider this case closed. You're camera should live a long a happy life :D

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ETTR is a generally debunked strategy, promulgated by the Luminous Landscape (which is actually as stupid as most of the other photog sites but arrogantly pretends otherwise). For one thing, RAW converters are optimized for correct exposure, not overexposure, so their tweaks will not benefit ETTR images. And for this particular camera, ETTR is an especially problematic practice. For one thing, the camera has no highlight rolloff capability at all, it simply hard-clips everything over 100 IRE. For another, the sensor is tiny and you often have very little light available. And for a third, the blacks come in around 20 IRE and in a log gamma ought to be lowered, not raised, along with the noise. You shouldn't overexpose your highlights, but for the BMD camera your shadows should be printed 20-25 IRE (by the log gamma, not by overexposure!) and then lowered accordingly in post.

 

Proper exposure is going to work best on this camera and most cameras in fact. It's the log gamma that raises the shadows for you going into the codec (this won't happen in a truly uncooked RAW). So expose to protect, but not overexpose, the highlights (because you have no choice), and monitor in "Video" mode to have the shadows crushed out for you, so you don't underexpose trying to force better contrast. I don't know if these cameras have waveform monitoring, probably not. But the auto-iris thing or zebras should get all but the finest specular highlights down below clip for you.

 

When I looked at the ProRes footage from Brawley I saw a lot of grain but I didn't see much opportunity for NR...I predict they are doing NR in-camera to try to save that sensor and then doing grain simulation to try to save the over-NRed image. I understand a lot of RAW implementations have NR baked-in as well, no idea about these cameras as you couldn't get ahold of one back when they were interesting.

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LOL. peederj. 

 

http://www.youtube.com/watch?v=PZeDFwTcnCc

 

 

The highlights all had boatloads of headroom on that clip.  You know, you'll feel better if you just break down and get one.  That way you won't have to waste so much time being jealous.  At the very least, you won't sound like a tool to people that actually know how to use the camera. 

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@HurtinMinorKey

 

Lets not close the case yet, because some things are still up in the air.

 

Others do not have this issue using AE, and your results testing the DNGs in Resolve have been positive, and we know the footage isn't a complete waste (tying to help the guy get a few hours of his life back ; ) .  What is going on in AE that would create this other than "pushing too far" because lets say a person DIDN'T push in post but still see the noise?  Could a export setting or project setting cause this?  Possibly a debayer issue?  Maybe AE is doing something "auto" during export?  

 

Basically, now that we're sure it isn't a hardware issue, it's obviously a workflow/software issue....but what? lol 

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If you shoot in PoRes it's hard-clipping everything over 100 for sure, unlike C300 you can't pull back the highlights. You mustn't ETTR with ProRes mode.

 

If it's raw mode you're just getting the vital image data in your shot at a sensible point in the DR of the sensor, using aperture ND and shutter. The ISO is post gain. Highlight recovery functions within reason!

 

That's what I've seen so far.

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What is going on in AE that would create this other than "pushing too far" because lets say a person DIDN'T push in post but still see the noise?  Could a export setting or project setting cause this?  Possibly a debayer issue?  Maybe AE is doing something "auto" during export?  

 

Basically, now that we're sure it isn't a hardware issue, it's obviously a workflow/software issue....but what? lol 

 

But he did push it in post, and that contributed to the noise. Even though it wasn't much, when you expose to the bottom part of the range in raw mode the camera is really sensitive (that's why its DR is better than other cameras in it's price range).  It's also why exposing to the right within reason (95% clipping on brightest spot), gets you the most control over your image.  

 

ETTR and clipping are two different things.  You should never clip.

 

JG, the most sensible point in the DR (as you said) for the BMCC is always going to be the least sensitive region (the right), such that you do not clip.

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So ideally, video display mode is like a rec. 709 in cam lut that acts as a better reference when shooting? I usually hit the iris button, remove the zebras so i don't clip any pixels, and go. I always hear this camera needs more light than most, and anything under or over ASA 800 is the devil.
Just a different beast for me i suppose.
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So ideally, video display mode is like a rec. 709 in cam lut that acts as a better reference when shooting?

 

I think that's a good way of thinking about it.  And remember, since you are shooting raw, you don't need to worry about what stuff looks like on the screen very much. Honestly, the POS screen on the BMCC is only good for two things, telling me what's in focus, and making sure i'm not clipping or drastically underexposing. 

 

I kind of think of it as shooting film with a light meter and no reference monitor.

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Word is BMD took a look at the DNSs and they are considering the camera defective.

 

You mean DNGs? Lol, i'm surprised. I'm going to see if i can recreate this issue in the lab.  I've seen it before in my cam, but only under similar circumstances as the OP. I hope the OP keeps us up to date

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On second thought...  If your camera is in good shape and you're not experiencing electro-static in your shadows regardless of exposure, unless you're just dying to know the turn out for the sake of knowing, It only took 48 hours for somebody on here to pull the "I'm the real deal" card, and tell me I'm an amateur.  Low and behold the company themselves have confirmed I wasn't crazy.  Jesus..   I never said I was Adrian Biddle asc.  I'm still learning this thing.

 

Thanks to "HurtinMinorKey"  for all your help, seriously! 

 

Thanks to Peederj for the reality check.  and good luck on the next Terrence Malick flick.  I'm sure he'll value your opinion.

 

smh.

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On second thought...  If your camera is in good shape and you're not experiencing electro-static in your shadows regardless of exposure, unless you're just dying to know the turn out for the sake of knowing, It only took 48 hours for somebody on here to pull the "I'm the real deal" card, and tell me I'm an amateur.  Low and behold the company themselves have confirmed I wasn't.  Jesus.. 

 

Thanks to "HurtinMinorKey"  for all your help, seriously! 

 

Thanks to Peederj for the reality check.  and good luck on the next Terrence Malick flick.  I'm sure he'll value your opinion.

 

smh.

 

Who called you an amateur? I'm interested in knowing the outcome cause I have seen similar phenomena, to a lesser degree, in my own shots when i under-exposed.  Did they explain your problems with aliasing too?

 

BTW OP=Original Poster (or thread starter)

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Who called you an amateur? I'm interested in knowing the outcome cause I have seen similar phenomena, to a lesser degree, in my own shots when i under-exposed.  Did they explain your problems with aliasing too?

They're deciphering the aliasing issue.  More than likely it's an AE downscaling problem.   A quick way to tell with the noise issue is a high contrast scene at ASA 400.  I was told it shouldn't be creating static like that at 800 regardless.   According to them, shoot at 800, 100% zebras, make them disappear, focus, record.   It likes light.

 

I'll pm you the outcome man.  As far as the amateur comment...  well:

 

http://youtu.be/PZeDFwTcnCc

 

It turned out you were right.  lol

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