Slog3 noise

[thebenstenator]

Hi all, just bought an A7SII.

 

Still trying to learn this camera as much as possible.

 

Anyway, I was excited for slog3 shooting, but whenever I turn it on the image looks very grainy and noisy, even at relatively low ISO's (1600 being the new low).

 

Even slog2 looks grainy.

 

For now I'm sticking to Cine profiles as they appear much cleaner.

 

How do you get a clean image in slog?

[bhaskar4uall]

am also feeling the same , Is any one have solution for this.

[willhazell]

I have the original A7S and have stopped shooting with s log it because it's so noisy.

 

Apparently if you over expose by one stop in s log the noise isn't as bad. 

[thebenstenator]

I'll have to do some more experimenting. But yeah, I was surprised to see that much noise.

 

Hope to see some more input!

[t79]

You should use the the god old zone system by Ansel Adams. Expose based on the highlights and "develop" the shadows in post-production.

 

Here is a nice intro by the lovely Camera Stor: 

 

<iframe width="560" height="315" src="https://www.youtube.com/embed/uUL_cYI_iYQ" frameborder="0" allowfullscreen></iframe>

[remylebeau]

You have to over expose s-log by 2 stops in most situations, I over expose 2.5 at night.

 

Slog curve is not linear the bottom 1/3 contains all the shadow and midtone information, the top 2/3 are highlight information. So it's actually easier to crush blacks than it is to blow out highlights. Watch Alistar Chapmans FS5 video, about half way through he goes very in depth about how Slog 2 and 3 work and how to expose them properly.

I've shot outdoors at night at 12,800 ISO and the result is very little noise in the shadows, by over exposing 2 stops then dropping the exposure 2 stops in post. What happens is you capture more detail in the darks and by dropping exposure in post you hide the noise. 

[loganhelps]

For SLog2 on my A7s I over expose by 3 stops for the best low noise performance. 

[tdavid]

The nature of applying a LUT to slog curves means you'll effectively 'crush the blacks' back and lift mids and highlights to return contrast and saturation (colour) to the flat slog image. So applying the LUT in itself will reduce your noise in the shadows as they will darken - however as mentioned by other posts, do over expose by a stop or two because the relatively low data rates recorded in-camera will mean the drop-off into shadows can be very harsh.

 

I recommend now with my a7s using a prores recorder to get more data to play with - still get lovely images without it with slog2, however having the extra data is a real plus when cutting in the footage with more data heavy cameras like the F5/55 etc.

 

(more on overexposing the a7s - with cameras like Sony F5 or F55, the large data rates mean you can still underexpose to get even more out of your highlights, and still not have noise issues in the shadows - you would rarely overexpose on these cameras like you need to with a7s due to the way they handle noise and highlights).

 

Tom

www.tomdavid.com.au