EPIC Noise/Grain

[Jason Comparetto]

@Gunleik -- Are you saying that I should set the camera at 320ISO when I shoot instead of 800ISO?

[Gunleik Groven]

@Gunleik -- Are you saying that I should set the camera at 320ISO when I shoot instead of 800ISO?

No.

What I am saying is that 800 @ daylight you have 1,25 stops highlight headroom, which means that if you overexpose slightly, you can recover that in post through either lowering the ISO in post OR grade from redlogFilm, which recovers the highlights in itself.

There is usually never a reason to lower the ISO on set from 800 and NEVER a good reason to set the ISO lower than 640 at tungsten/320 at daylight.

[David Battistella]

No.

What I am saying is that 800 @ daylight you have 1,25 stops highlight headroom, which means that if you overexpose slightly, you can recover that in post through either lowering the ISO in post OR grade from redlogFilm, which recovers the highlights in itself.

There is usually never a reason to lower the ISO on set from 800 and NEVER a good reason to set the ISO lower than 640 at tungsten/320 at daylight.

We are of two minds on this but I do not want to derail the thread either.

Obviously filters come into it and shutter speeds (electronic at that)...

My point was more about how much light you let hit the sensor.

As this relates to the original post.

Let's say you rated at 800 ISO, and have your camera set there and you open to f4 and it looks good. Well you are underexposing (or getting 1.25 stops of headroom) as you put it. In this case it would have been better to open up to 2.8 (gain the stop) and have more light hit the sensor (rather than starve it one stop) in a tungsten situation.

I know there are many variables, but on shoots like the one in this thread, you need to do two things.

1. get more light on there.
2. Use a faster lens.

That's it.

David

[Gunleik Groven]

We do agree that up'ing the ISO does no-good :)

There is some issues with full exposure at tungsten if you WB to 3200, as you risk putting a cap on the RED channel and get some unwanted artifacts from that.
But we are into details very far off the OP, I agree... :)

The OPoster just needed more light hitting the sensor...
Agreed on all points as to that.
And it gets even worse with the crop-factor as to noise.

But this seems to take some time to get aquianted to, so I wouldn't really call it a mistake, more like part of the process of gaining experience... :)

[David Battistella]

I agree Gunleik.

There are no mistakes, just best practices.

If I was in Lee's shoes I might have.

1. Captured 4khd over 3k ( for less noise and punch ins later if needed)
2. Captured at 8:1 over 10:1
3. Tried to get a bit more light in there.
4. A 200mm F2.8 is pretty fast for a long lens.

Boosting ISO in post is a bit like using db gain on a traditional ENG camera. Any amount you push it will increase noise and noise is often most visible in the blacks.

All of this depends on the situation lee was facing and the decisions he has to make to do the shoot. Let's say 3k might have been chosen to save disk space. I don't know. But it's best to know how the camera will react by testing.

David.

[Lee Dashiell]

@Lee

Lee,

If you would like me to send you a copy of the snapshot with the RDM I created, I would be happy to help you out by e-mailing it to you.

Pushing the ISO to 1000 is always going to increase noise in the black areas, but with a few easy post strategies you can get a really good result from this footage, probably without using NEat video.

David

I ended up using Redcine-X to make the correction after seeing that the Neat Video render time was going to be 4 days. There's a slight bit of noise that still exists in the image but I'm pretty pleased with what I have considering what it looked like when I first opened the files. I will say that the 1080 image being viewed on a 17" Panasonic monitor via SDI was very clean. If you look back at the shot with Leonardo Decaprio shot on Epic lighting a match http://www.youtube.com/watch?v=rLxQiI8c1Bs compared to the shot I have that's dropping a hard shadow, bright enough for a large room full of people to see a speaker at a podium, you would have thought that I would have been safe.

[David Battistella]

I'm glad it worked out lee.

I'm constantly surprised at how sharp the rendered footage looks when you drop the resolution.

A lot can be done in RCX just with ISO and curves and white balance.

David

[Lee Dashiell]

I do appreciate all of the feedback, suggestions, and experience that is shared here. I've been in this business for over 20 years and learn something new every day. The day I think I know it all is the day I should depart from the industry. That being said.....I think I'll be here for a long time.

[Paul Leeming]

Hi Lee,

I had a quick crack at the image to get the following result (1920x1080 JPG, right click to save full size version):



Here's my RMD settings so you can apply them to your clip if you like what you see. Nothing done to the clip outside of RedCine-X PRO build 8 adjustments.

HTH!

Cheers from Japan,

Paul :)

[Rob Ruffo]

Agree. But it's parlour tricks. ISO, HEadroom, whatever. Knowing how and where the sensor reacts is important, but at the end of the day, it's how much (or little) light you let hit the sensor and that is always controlled by aperture, nothing else.

David

This not true unless you are shooting rough ENG work. Otherwise use NDs.