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Noisy 2k 120 FPS Red Footage

Daniel Soderberg

Daniel Soderberg

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Daniel Soderberg said:
I am trying to figure out if my Red One MX is creating overly noisy images. The 2k 120fps clips seem to exagerate the noise dramatically.

Attached is a short Red Raw file: https://www.yousendit.com/download/YTYrRGwrcTIyWGRjR0E9PQ

Thanks ahead of time for opinions.

-Daniel
Click to expand...

Yeah, it can be challenging. Couple of things working against you.

The super-fast shutter ensures minimal light can get to the sensor while at the same time you are cropped right in the middle of the sensor so it's 1:1 instead of 4:1 so no beautiful oversampling.

Looking at your R3D, hard to tell if it was lit or not. Was it a quick test or on a lit set?

The best high speed footage seems to come from extremely well lit or outdoor daylit scenes.
 
it looks like it is underexposed. 2k 120fps is better to light it like iso 320 to get a low noise level. be carefull for yor highlights
 
Thanks for the info so far guys...
It was somewhat lit, but I wanted a dimmer, grungy feel to it, so I didn't want to blow the hell out of it... I am pretty discouraged that this situation with decent light, and nothing being off in settings would create such horribly noisy footage...

@Robert: Is it really better to shoot at 320 ISO? I was under the impression that no matter what, because the sensor is rated for ISO 800, that the camera will always perform best at that ISO.
 
Hey Daniel,

Just to leave no stone unturned, you did change the lighting to accommodate the faster shutter didn't you? You will lose a few stops compared with shooting 24FPS.

Almost looks like you lit for 24FPS, 180˚, 800ASA and just changed the camera settings to 300FPS. Not much risk of overexposing indoors at 300FPS.

My advice would be to light bright to get a clean frame, then achieve your final look in post. Think of it as day for night! ;-)

Remember, you are taking a hit on light (shutter), compression and 1:1 cropped sensor so you need to feed it the best source possible if you want great results.

Kind of like taking a sports car and driving uphill in the rain at night with the lights off. You can still go fast but you'd better keep your wits!
 
Im using 120fps in full sun almost daily and as long as I have plenty of light I never see any problems with noise. Its when you start to see the histograph smashed to the left side you tend to notice noise in some of the lowlight areas.
 
It sounds like you are trying to shoot a WYSIWYG. This is inappropriate for this type of shot when shooting RAW.
You have to "expose to the right", maintain your lighting ratios, and then dial your curve down in post.
Use you light meter. Use your Histos.
Good Luck!

test test test.
 
I noticed more edges you have in the picture, such as forest, or having many pixels moving, the 2k 300fps footage look really noisy.
 
Daniel Soderberg said:
Thanks for the info so far guys...
It was somewhat lit, but I wanted a dimmer, grungy feel to it, so I didn't want to blow the hell out of it... I am pretty discouraged that this situation with decent light, and nothing being off in settings would create such horribly noisy footage...

@Robert: Is it really better to shoot at 320 ISO? I was under the impression that no matter what, because the sensor is rated for ISO 800, that the camera will always perform best at that ISO.
Click to expand...

At 120fps, if you have bright enough lights, it is definitely better to shoot ISO320. If not ISO500 or 640 would be better than 800. ISO 800 is good for normal shooting on the MX, but when you are starved of light and cropping 2K, you should shoot ISO320 as you are effectively underexposing the sensor by about a stop and a half.
 
eric

I don't understand that because Epic is always shooting at ISO800 no matter what.
 
Kaku,
That's not entirely accurate. ISO800 is just a good starting place. Selecting a lower ISO will give you more shadow protection (less noise), a high one will protect the highlights, but at risk of more noise.
 
My understanding is shooting at none native ISO is just changing the metadata and not affecting how RED is recording the sensor. By changing the look by changing the ISO, it would leads you to adjust the Iris, shutter speed, or even lighting, which ending up getting the different characteristics but say if you have different ISO settings but you keep everything else the same, the RAW data would be exactly the same.

edit:after changing the ISO, by initiating black shade might provide different noise characteristics though.
 
Kaku Ito said:
eric

I don't understand that because Epic is always shooting at ISO800 no matter what.
Click to expand...

The "native" ISO of the Red MX sensor is the same as the original M sensor, ie ISO320 - it's just much cleaner in the blacks, which means you can rate it at ISO800 ( ie underexpose by a stop and some - which protects highlights ) for general exposure in a lot of situations, without excessive shadow noise, and it will be fine. That's the only reason Red made ISO800 the default.

You can check this easily yourself - if ISO800 was the native RAW sensitivity, then switching between ISO800 and RAW view would have no change in exposure (although colour temperature might change if you're not set to Daylight 5600K). That's not the case, but it is the case if you dial the ISO to 320.
 
Kaku Ito said:
My understanding is shooting at none native ISO is just changing the metadata and not affecting how RED is recording the sensor. By changing the look by changing the ISO, it would leads you to adjust the Iris, shutter speed, or even lighting, which ending up getting the different characteristics but say if you have different ISO settings but you keep everything else the same, the RAW data would be exactly the same.

edit:after changing the ISO, by initiating black shade might provide different noise characteristics though.
Click to expand...

You are correct here - except I don't think you will get a different noise characteristic with different ISOs - it doesn't affect the RAW. RAW signal to noise ratio is really only affected by exposure and temperature.

Going to 2K 120fps is shortening exposure considerably, so theoretically you should black balance at the intended frame rate. In practice I've found Red M and MX black balances to be extraordinarily stable with temperature and exposure, with no actual need to black balance in non-extreme temperature environment changes or when changing framerates from 25 to 100fps which is the range I've alway worked in 50Hz PAL UK land.

Going to framerates significantly below 24/25fps, I probably would black balance again at the shooting framerate, and then again when going back to "normal" framerates, as it's longer exposures that tend to exaggerate any sensor noise patterns and marginal pixels.

This is similar to taking stills on Canon/Nikon DSLRs. I've never had noise issues going to shorter exposures, only on long exposures.

I have heard of some codec issues with framerates higher than 100fps, approaching 120fps on the Red Ones though. So I can't rule that out here , as I have no real experience of shooting above 100fps.
 
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