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Help With Raven Noise Requested

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Miles Levin

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Hello there,

I rented a Raven last week and shot a short film with it. The results were unfortunately very noisy, and I can't figure out just why or how to fix it. Ideas appreciated!

Here were my settings:
4.5k 4:1
Redlogfilm
Dragon Color 2
800 ISO
Fan set to 41C
Always Exposed to the Right

It was a hot day, but the camera consistently reported a green Cal/Te symbol. The fan was going even when recording.

The shadows and mids are VERY noise heavy, even after a healthy grade of bringing the shadows back. The scenes that were slightly darker are even harder to save. I just don't know how to save this. I know Resolve well and am hoping the answer is there. Advice appreciated.

Here are two reasonably exposed clips UNGRADED: https://www.dropbox.com/s/didms9x7aqk4q2v/A002_C052_0727L8.mov?dl=0
Here is another: https://www.dropbox.com/s/nkex12h078xnr3j/A002_C042_0727HT.mov?dl=0

After dropping shadows and adjusting mids, doing a basic grade, it turns out about the same.

Thank you for any ideas!
 
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Hmm, at 800 that seems surprising. Do you mind uploading an R3D still or two? Maybe we can find something in the metadata.
 
Yeah, very bummed. I could have used my dlsr and saved a ton of money. Holding out for a tip that makes this experience all worth while. Otherwise extremely disappointed. Wanted to buy one until this happened.
 
Miles Levin said:
For sure, the links to some prores proxies are in the above if that helps, but here are some stills- https://www.dropbox.com/s/ycct2bg91m4sgeu/Screen%20Shot%202016-07-31%20at%203.23.17%20PM.png?dl=0
https://www.dropbox.com/s/e9ddyegp9pllm8z/Screen Shot 2016-07-31 at 3.21.04 PM.png?dl=0

The first one is graded, the ungraded is even worse.
Click to expand...

Cool. Specifically asking about the r3D stills because we can't access metadata in your compressed files. If you upload an R3D still we can open in RCX and have a peek behind the curtain. Maybe there's something lurking in the details that we could help uncover.
 
Just a quick look at the histogram says that it's 2-3 stops underexposed. Don't judge the log image for proper exposure, as the shadows are always going to be noisy since they are meant to be crushed (same applies to dslr types that shoot log such as the c100). When shooting, definitely set the color space to dragon color 4 instead of redlog film, then when in post you can change the raw file to redlogfilm if you want to start from there while grading.

Sorry, it definitely sucks to find out your footage is almost unsalvageable, but you should definitely read about how RED cameras expose differently and how the exposure tools work so you know how much light you really need. The Red picture is downright amazing - given enough light.
 
Hey Miles, I know this doesn't help you - but I made the same mistake on my first project when I received my Scarlet-MX. I found that the style of shooting I used to do with my 5DII did not bring the best out of the sensor when shooting RED. The beautiful images that come from RED sensors usually require a some good light, I have found. I didn't make the mistake again, if that's any consolation!
 
Josiah Duncan said:
Just a quick look at the histogram says that it's 2-3 stops underexposed. Don't judge the log image for proper exposure, as the shadows are always going to be noisy since they are meant to be crushed (same applies to dslr types that shoot log such as the c100). When shooting, definitely set the color space to dragon color 4 instead of redlog film, then when in post you can change the raw file to redlogfilm if you want to start from there while grading.

Sorry, it definitely sucks to find out your footage is almost unsalvageable, but you should definitely read about how RED cameras expose differently and how the exposure tools work so you know how much light you really need. The Red picture is downright amazing - given enough light.
Click to expand...

Yeah, this seems to be the culprit. Have you worked with log images before...exposing and understanding the theory behind how you want to expose log? I personally shoot log with shooting LUTs...but frequently toggle my log on/off and check to make sure I'm exposing for the highlights while maintaining a solid noise floor by keeping optimal exposure in the 40-50IRE range (not a golden rule, just what I like). To me, you would have to be at around 2500iso to be properly exposed given your conditions and not pushing the sensor as hard as 4000 (even though that is truly the better ISO point).

If you're coming from a non-log world, I would definitely take a look at the many resources on how to expose log images...and if you are familiar then maybe your eye just got tricked on this one. Toggling between RedLogFilm and DragonColor on set will really help you get an idea. If you're coming from the DSLR world where you're seeing an image with curves and in a non-logarithmic color space, DragonColor is going to be a better jumping off point while you're on set. Utilize your raw as much as you can and use some solid denoisers. I'm sure you'll still be able to tell your story...though it is a bummer for sure.
 
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And to add to the very helpful advice above, I would advise always shooting camera tests if possible a few days prior to the shoot date, and bring along a color chart if possible (like the DSC Chroma Dumonde or the inexpensive X-Rite Color Checker Video), and try some bracketed exposures and see how they look. I generally tell people to over-expose about 1/2 a stop to avoid noise, but at the same time keep a close eye on the specular highlights (light bulbs, headlights, blown-out windows, etc.). When in doubt, add more fill during production and then plan to add contrast in post. Key-to-fill ratio is very important.
 
As others have said, this footage is very underexposed. 4000ISO is the real ISO.

The Histogram would have been your friend here. It's clearly clumped to the left, and the "noise" goal posts on the left - warning of noise in blacks - are very, very full.
 
original poster mentioned they ETTR - but certainly the histogram would not have shown that? and the stop lights for underexposed did not light up?
But DragonColor would have made it easier to see you were underexposed
and maybe factory reset is best whenever you get a rental camera - some settings could cause you trouble I suspect
Also as mentioned - you should have black shaded since you have no idea what temp or conditions camera was used before you (rental, right?)
I have Raven and black shaded out of the box - no noise issues whatsoever even underxposed

BTW I have used Red Giant plugin for PRemier on Noisy Scarlet MX footage - might help you resuce the footage - seems to handel a few stops underexposed
 
just try and switch in RCX to Redgamma 4 and see how dark it is, then increase ISO till it looks right.
You will end up with ISO 4000 like others already said. I personally don't monitor with Redlog while shooting,
any log shooting needs a lot of practice to get exposure right and you need to exposure with the exposure aids of the camera...
If you want to expose more to the left for style etc. use a lower ISO and you still get fairly clean footage.
 
Brody_B said:
First thing that comes to mind is Black Shading. Was it done?
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the epic dragon comes with 800iso set.. if raven is the same..this gives you a stop of highlight protection .. but shadows can become noisy if you don't watch the shadow goal posts.. best solution is to drop to iso400 .. but since its too late, and the noise is too annoying for you .. buy something like neatvideo , and settle for half the resolution you might have planned on (ie, 2k or 1080p) . the downsample will reduce any noise reduction artifacts

before doing the downsample .. if you haven't done before.. i recommend everyone exports a resolution chart using your export/resize settings from whatever app you're using(crop it to the same resolution as your 4.5k footage) .. and see how your app performs on it.. if the output looks too sharp, or produces moire .. apply a Gaussian blur of 0.25 - 1 pixels prior to downsampling (to taste .. 0.5 should be good)
 
they better start a class specifically for raven people coming from dslr, i have had to hold my own in my office for a few directors that jumped on the raven train.
 
this is the same thing I tell my assistant and second shooter with our gh4+pix, over expose and bring down a hair. Is under exposing a canon thing? We have always over exposed and brought down going back to the nikon f2. In any case we live and we learn!
 
Steve DiMaggio said:
Is under exposing a canon thing?
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I don't think under exposing is ever "a thing". But there's a difference between "correct" exposure (if there is such a thing—let's say expose for final look) and ETTR.

I would not expose to the right unless I have a picture profile that gives me equal fidelity over the stops into the highlights. Log curves typically do this and they allow you to ETTR and then pull everything back with maintained tonality. On the other hand, a traditional video gamma curve might have a pronounced 'knee' built in. Putting your critical image information in the area designed for compressing highlights might net you much less image information where you wanted to keep it. And since these type of cameras nowadays don't really suffer a lot from noise, it's better to expose more traditionally in certain scenarios.

I haven't looked at the images in this thread, so it's not a comment on that—those seem to be under exposed based on comments.
 
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