EX1 Noise In The Shadows?

[Jonathan Bland]

Hi folks,

I saw another post some time ago about noise in the shadows under halogen lighting.
I can't seem to find it..... can anyone point the way?

Why am I getting so much noise in the shadows under halogen lighting? Is there anything I can do?

[Dominik Seibold]

Yes: Maximize the use of the dynamic range of the sensors (which is very good compared to other sub 10k-camcorders), by using the cine1-gamma (it's got the most steep curve at highlights compared to all other curves, so it minimizes the chance, that the picture looks overexposed because of a flat curve, though there's still some unused exposure-headroom) and using above-100IRE-information.
Also think about decreasing the contrast in the shadows a bit, to get a more punchy look. This of course will decrease the shadow-noise (transforming grayish noisy shadows to more black shadows).
I wrote a FCP-plugin for altering the contrast in the way you want it to:
http://www.dvinfo.net/conf/non-linea...st-plugin.html

[Dominik Seibold]

Originally Posted by Jonathan Bland

Why am I getting so much noise in the shadows under halogen lighting?

I forgot that part...
Because halogen light has a lower white-temperature, so especially the blue (low wavelength) channel is darker and has to get amplified (done by the white-balance-feature of the camera) to satisfy the specification that white means the signals of the red, green and blue channel are equal strong. And that amplification of course also amplifies noise.
If you want to know, why the blue channel gets dark at low white-temperatures and what white-temperature actually means, read that article:
http://en.wikipedia.org/wiki/Thermal_radiation
If your halogen-source is bright enough, it makes sense to use a blue-filter in front of your light-source or (if there are many light-sources) your lens, to fit the optimal white-temperature of the camera (optimal means if no channel gets amplified then something white results in red=green=blue).

[Jonathan Bland]

Big thanks Dominik :)

I guess I never expected to see so much noise with the EX1.

I tried to plug your filter in but it does not show up in the FCP effects list.
Library/ Application Support/ Final Cut Pro System Support/ Plugins.

I know I can crush the blacks in post to bring down this noise but am wondering if there is another way. I've tried Bill's Cine 1, Cine 3, Cine 4 and another STD Gamma, HiSat3 and none of them help to reduce this noise in the shadows.

I remember reading a comment 2 - 3 months ago from another person on this site who was a little surprised with the noise as well.

[Dominik Seibold]

Originally Posted by Jonathan Bland

Library/ Application Support/ Final Cut Pro System Support/ Plugins.

No, it's ~/Library/Plug-Ins/FxPlug/

Originally Posted by Jonathan Bland

I know I can crush the blacks in post to bring down this noise but am wondering if there is another way. I've tried Bill's Cine 1, Cine 3, Cine 4 and another STD Gamma, HiSat3 and none of them help to reduce this noise in the shadows.

Cine4 and the stds are bad, because they've got a high shadow-contrast, so the noise in there gets even more accentuated.

Originally Posted by Jonathan Bland

I remember reading a comment 2 - 3 months ago from another person on this site who was a little surprised with the noise as well.

The ex1 produces not so much noise. It's more a high shadow-contrast, which makes it more visible. If you would compare a picture of an ex1 (with a cine-gamma) to a picture of for example a fx1 of the same scene, the first thing you would notice would not be higher noise of the ex1 in the shadows, but a much more flat/high-dynamic-range look. You have to realize that those gammas are coming from very professional 100k-cameras, which probably have higher-quality electronics/better SNR.

[Jonathan Bland]

Hi Dominik,

I'm running 10.5.4 on a Macbook Pro and do not see this ~/Library/Plug-Ins/FxPlug/. It's just not there.

I understand your comment on the better cameras with their SNR and the EX1's high/ flat dynamic range look.

Been seeing some great things from the new Canon 5D.

[Dominik Seibold]

Originally Posted by Jonathan Bland

I'm running 10.5.4 on a Macbook Pro and do not see this ~/Library/Plug-Ins/FxPlug/. It's just not there.

You have to create it! I guess I should make an installer for it...

Originally Posted by Jonathan Bland

I understand your comment on the better cameras with their SNR and the EX1's high/ flat dynamic range look.

Good. What I was trying to say is, that other sub 10k-cameras (except Canon 5D ;)) would look much noisier if you would apply the same gamma-curves to their pictures.

Originally Posted by Jonathan Bland

Been seeing some great things from the new Canon 5D.

Did you see 1080p-footage from it? Do you have a link? I read about it and am very interested.

[Jonathan Bland]

for the 5D there is the Canon site:

Canon Digital Learning Center - Sample EOS 5D Mark II Video: Reverie

and this blog:

ProLost: Reverie

I'll make a folder for your plug in but I'm not going to hold me breath for FCP to know the file path.

[Michael Maier]

I found your post quite interesting, but can't help to think something is getting lost in translation here. You are in Germany so I'm thinking your first language is German, so maybe that's why I'm confused.

Originally Posted by Dominik Seibold

Yes: Maximize the use of the dynamic range of the sensors (which is very good compared to other sub 10k-camcorders), by using the cine1-gamma (it's got the most steep curve at highlights compared to all other curves, so it minimizes the chance, that the picture looks overexposed because of a flat curve, though there's still some unused exposure-headroom) and using above-100IRE-information.

Actually, Cine 1 and Cine 4 have the same dynamic range. They clip on the same point too, so Cine 1 doesn't make more use of above-100IRE info.

Originally Posted by Dominik Seibold

Also think about decreasing the contrast in the shadows a bit, to get a more punchy look.

Did you mean "increasing" contrast? Decreasing it won't get you a more punchy look.

Originally Posted by Dominik Seibold

This of course will decrease the shadow-noise (transforming grayish noisy shadows to more black shadows).

This is hardly a good solution for noise. All you are doing is crushing your blacks in camera. You can do that in post too. Grayish blacks is a way to get more dynamic range out of the camera. Most HD shot for filmout or color correction go for "grayish" blacks or a flatter look to leave more options for post-production.

[Piotr Wozniacki]

Originally Posted by Michael Maier

Did you mean "increasing" contrast? Decreasing it won't get you a more punchy look.

I think we should agree on a common and unambiguous definition of "contrast", and hence increasing or decreasing it.

In the common sense, high contrast = punchy, with less gradation.

In the specialist jargon: high contrast = a lot of mid tones (gradation), i.e. less "punchy".

When you adopt the latter concept, the somewhat vague description of Cine Gammas in the EX manual adopt a bit more meaning :)

[Dominik Seibold]

Originally Posted by Michael Maier

Actually, Cine 1 and Cine 4 have the same dynamic range. They clip on the same point too, so Cine 1 doesn't make more use of above-100IRE info.

Yes, but because of the heavy highlight-compression of cine4:
-the picture often looks overexposed/too bright, although nothing clipped, leading the cameraman to reduce the exposure and loosing signal/noise-ratio.
-highlight-information gets lost because of mpeg2-quantization
(The above-100IRE-hint is independent from the cine1-hint. You should check the parenthesis ;))

Originally Posted by Michael Maier

Did you mean "increasing" contrast? Decreasing it won't get you a more punchy look.

With "contrast" I mean the slope of the gamma-curve at a specific brightness-point.
Decreasing shadow-contrast automatically leads to increased midtone-contrast, if you think about a s-curve (like I did).

Originally Posted by Michael Maier

This is hardly a good solution for noise. All you are doing is crushing your blacks in camera. You can do that in post too. Grayish blacks is a way to get more dynamic range out of the camera. Most HD shot for filmout or color correction go for "grayish" blacks or a flatter look to leave more options for post-production.

I didn't want to recommend crushing blacks in the camera, but a smooth gradual increase of contrast from black to midtones in post-production. That's why I mentioned my plugin, because with that you can do exactly that.

[Michael Maier]

Originally Posted by Dominik Seibold

Cine4 and the stds are bad, because they've got a high shadow-contrast, so the noise in there gets even more accentuated.

Again, Cine4 is the same as Cine1. Just the midtones are brighter. Cine4 is not bad at all. The shadows in Cine1 and Cine4 are the same. So I don't understand why you say Cine1 makes cleaner shadows.

Originally Posted by Dominik Seibold

The ex1 produces not so much noise. It's more a high shadow-contrast, which makes it more visible.

Don't really understand what you mean by "shadow-contrast" here.

Originally Posted by Dominik Seibold

I forgot that part...

Because halogen light has a lower white-temperature, so especially the blue (low wavelength) channel is darker and has to get amplified (done by the white-balance-feature of the camera) to satisfy the specification that white means the signals of the red, green and blue channel are equal strong. And that amplification of course also amplifies noise.

If you want to know, why the blue channel gets dark at low white-temperatures and what white-temperature actually means, read that article:

Thermal radiation - Wikipedia, the free encyclopedia

I have also found filming under HMIs and Daylight the EX1 produces a cleaner picture than under tungsten lighting. Even more interesting is that dialing the white balance down to about 2700-2900 also “seems” to produce cleaner images under the same circumstances. Boosting the gain up produces less noise with a white balance of 2700 under tungsten lighting than using a proper white balance temperature. It seems to be related to the red channel or maybe the IR contamination.

Originally Posted by Dominik Seibold

If your halogen-source is bright enough, it makes sense to use a blue-filter in front of your light-source or (if there are many light-sources) your lens, to fit the optimal white-temperature of the camera (optimal means if no channel gets amplified then something white results in red=green=blue).

Using a filter over the lens sounds more practical than gelling every light. Problem with that is that first you would have one more filter over the lens since you must use a IR cut filter with the EX1. Second problem is speed. What filter are you using over your lens and what grade?

Originally Posted by Dominik Seibold

Yes, but because of the heavy highlight-compression of cine4:

-the picture often looks overexposed/too bright, although nothing clipped, leading the cameraman to reduce the exposure and loosing signal/noise-ratio.

Well, that’s a mistake of the operator not the Cine4. That shows the need of a waveform monitor to proper check levels of to know how the gamma you are using behaves.

Originally Posted by Dominik Seibold

With "contrast" I mean the slope of the gamma-curve at a specific brightness-point.

Decreasing shadow-contrast automatically leads to increased midtone-contrast, if you think about a s-curve (like I did).

Do you mean dynamic range when you say contrast? Decreasing dynamic range would of course produce a punchier look.

By shadow-contrast do you mean just contrast? The difference between light and dark areas?

[Michael Maier]

Originally Posted by Piotr Wozniacki

I think we should agree on a common and unambiguous definition of "contrast", and hence increasing or decreasing it.

In the common sense, high contrast = punchy, with less gradation.


In the specialist jargon: high contrast = a lot of mid tones (gradation), i.e. less "punchy".


When you adopt the latter concept, the somewhat vague description of Cine Gammas in the EX manual adopt a bit more meaning :)

I’m sorry but I don’t think we need to agree on any common term to define what you are talking about. The term already exists and it’s called dynamic range.

More contrast means more punch in the common or professional sense. Now the ability to record more contrast which is what you are talking about is defined by dynamic range.

High dynamic range = a lot of mid tones (gradation), i.e. less "punchy".

[Dominik Seibold]

Originally Posted by Michael Maier

The shadows in Cine1 and Cine4 are the same. So I don't understand why you say Cine1 makes cleaner shadows.

No. The shadows of cine4 and the shadows of the stds are the same. That's the cause why cine4 is called "video bright". Cine1 has much darker shadows (and darker mids) than cine4.

Originally Posted by Michael Maier

Don't really understand what you mean by "shadow-contrast" here.

With weaker shadow-contrast I mean that the slope/derivation/rise at the lower end of the gamma-curve is more flat, so the shadows look darker. A steep slope of the curve at the lower end would accentuate the shadows, because steep means, that the same change of input results in more change of the output. Flat means the same change of input results in less change of output - and then because we're coming from black (we're talking about the lower end) it looks nearer to black.
If you don't understand me, I can create a graphic for explanation.

Originally Posted by Michael Maier

must use a IR cut filter with the EX1.

I don't have problems with IR, although I don't use an IR-filter.

Originally Posted by Michael Maier

Second problem is speed.

That's why I wrote "if your halogen-source is bright enough".

Originally Posted by Michael Maier

What filter are you using over your lens and what grade?

I've got halogen-lights with blue-filters attached and some kind of a gas-light which produces daylight-white.

Originally Posted by Michael Maier

Well, that’s a mistake of the operator not the Cine4.

Yes, it's the mistake of the operator to use cine4, if the scene doesn't have much dynamic-range. Flat scenes want to be shot with cine1.

[Jon Sands]

Originally Posted by Jonathan Bland

I remember reading a comment 2 - 3 months ago from another person on this site who was a little surprised with the noise as well.

Were you thinking of my thread? Should footage be this noisey? - The Digital Video Information Network