Sony a7s ii vs Blackmagic Pro 6K noise in low light

O

orange

Active member
Hi! Can you help me in this decision? I am shooting a short film with the BM Pocket Pro 6K and everything has gone well until we started shooting exterior night scenes in natural street lights. I had to apply ISO 3200 to get a decent image and the noise is pretty evident. I have several other exterior night scenes left to shoot and I am thinking about renting a Sony a7s ii instead of the BM. Would this camera give me lower noise? I am aware of some color differences but at this kind of scenes the colors mostly are black, blue, brown etc so I would think the colors could be corrected in post. Renting the other camera would increase cost so it has to be worth it... Thanks for any advice.
 
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Can you post a short clip of the noisy BM footage?

(For evaluation because I personally don't think 3200 is really that noisy on that camera, but the a7SII would likely be cleaner but softer.)
 
Can you augment the lighting with LEDs & colored gels to match the street lights?

How does the footage you already shot look after de-noising?

The A7sII's compressed, 8-bit, low-bitrate codec won't allow much room for color correction.

I haven't shot with the 6K Pro, but since 3200 is it's second native ISO, I wouldn't think that it would be that noisy, unless the shot was under exposed.
 
Still image from video of ISO 3200 image, all natural lighting. Notice the sky, full of noise
 

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That's too compressed to be able to tell anything from it.

And we need motion so we can see the amount of noise dancing that's taking place.
 
Imamacuser said:
Can you augment the lighting with LEDs & colored gels to match the street lights?
How does the footage you already shot look after de-noising?
The A7sII's compressed, 8-bit, low-bitrate codec won't allow much room for color correction.
I haven't shot with the 6K Pro, but since 3200 is it's second native ISO, I wouldn't think that it would be that noisy, unless the shot was under exposed.
Click to expand...

The scenes are mostly wides and are action scenes, so it is difficult to have a LED make any difference. No budget for HMI's.
I tried some de-noising and it improves, but I prefer to work with material that comes out good from the camera, de-noising tend to make the image softer and flatter.
Actually as you I thought being native ISO would be better, but 3200 looks extremely noisy, while 1250 is better. Only with action scenes I don't want to work with wide apertures, focus becomes an issue. (minimum 2.8, preferably 4)
What is "underexposed" in a night scene? You can expose for skins when the person is under a street light but most of the image would be underexposed as long as you don't light the area...
 
NorBro said:
That's too compressed to be able to tell anything from it.

And we need motion so we can see the amount of noise dancing that's taking place.
Click to expand...

I know, but if you look closely above the car you can see that the sky is not uniform as it should be, it is full of huge grain (noise). It is not from the compression of the photo, it is there in the hi-res version as well. Let me check if I can post a video
 
Take a look at the video below around 3:07 in 4K+ (and other videos) and see if it can help you.

IMO, what you have looks like compression blocks/artifacts, not noise...

The focus also looks to be on the concrete and not the sky, which would blur the sky and could mess up the image based on the circumstances (night time, multiple lights, shallow DOF).

https://www.youtube.com/watch?v=yAFkEwZzKnE
 
No, but the type of individuals who use these cameras likely do not shoot lower than PR422, with the remaining options being HQ or a form of BRAW.
 
Once we hade both cameras we did some tests in exterior low light and came to the conclusion that the Sony A7s ii's noise is more or less equal to the BM 6K Pro's within ISO's of 800 to 3200 (using SLog2 on the Sony), so we kept shooting with the BM, since it has many other benefits. Not sure if our tests are thorough enough, so make your own in case you have a similar situation... Something that also became evident is that the natural "noise" of areas out of focus will get especially noisy in low light using ISO's over 800 (like someone commented). Another consideration is that noise will be more evident in locked-down shots than moving ones. Still learning. Thanks for your input
 
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