EX1 in dimly lit churches: Settings to limit noise when shooting with +3db gain

[Mervin Langley]

I would appreciate advice to limit noise when i have to shoot with gain to increase DOF. I have noticed, when using a variety of PP settings, a great deal more noise than I would like. Would the crispening function help?

Thank you,

Mervin Langley

[Sebastien Thomas]

Depending on what you're shooting.
1) if you have not much action, turn shutter off. This way, you may gain more light, and avoid using gain.
2) use gain +3, +6 MAX.
3) go with cine3/4 gamma curve (as far as I remember)
4) dark footage without gain may be better in post than brighter with gain and noise
5) I shot on a the Notre Dame church in Paris, France, on december. Check footage here :
http://www.lecentre.net/blog/archives/185
http://www.lecentre.net/blog/archives/183

Hope this will help.

[Piotr Wozniacki]

Originally Posted by Sebastien Thomas

Depending on what you're shooting.
1) if you have not much action, turn shutter off. This way, you may gain more light, and avoid using gain.
2) use gain +3, +6 MAX.
3) go with cine3/4 gamma curve (as far as I remember)
4) dark footage without gain may be better in post than brighter with gain and noise

Agreed on all points BUT 3) - in lowlight, NEVER use Cine gammas; they steal too much light, beginning in mid-range! Use STD1 if you want to compress blacks (along with their noise); if you really need more detail in darker areas, use STD4 to stretch blacks (but noise will kick-in).

[Sebastien Thomas]

Originally Posted by Piotr Wozniacki

Agreed on all points BUT 3) - in lowlight, NEVER use Cine gammas; they steal too much light in mid-range! Use STD1 if you want to compress blacks (along with their noise); if you really need more detail in darker areas, use STD4 to stretch blacks (but noise will kick-in).

Of course, use STD. cine gamma was a typo :)

[Robert Young]

Sebastien
Nice footage of Notre Dame.
I am amazed at how steady your handheld shots are. I have had generally poor experience trying to shoot the EX handheld.

[Sebastien Thomas]

Originally Posted by Robert Young

Sebastien
Nice footage of Notre Dame.
I am amazed at how steady your handheld shots are. I have had generally poor experience trying to shoot the EX handheld.

hand held does not mean you can't use things around you to help stand still :)
the camera was not put on something alone, it hand help, but i was using the wall for the prying girl.
having the right hand in the handle and the left one on the bottom, sustaining the camera and pulling focus is a nice try. be carefull that the camera gets heavy really fast anyway :)
The trick here is to move. Don't try shooting something when you can't stand still. Change position, try to move around...
Next time I need somthing like this I may be using a shoulder mount anyway.

[Piotr Wozniacki]

I might add that when I shoot without any support, I always place the EX's back against my abdomen - hanging on the original strap around my neck. This is possible thanks to the rotatable handgrip, and allows for prolonged handheld shooting without any fatigue whatsoever. The only caveat being the perspective may be a little awkward for interviewing a person, standing close to me...

[Mervin Langley]

Thanks for the information. Here is a clip that I recorded at a wedding last week:

http://langleyvideography.com/Langle...68K_Stream.wmv

[Serena Steuart]

Originally Posted by Piotr Wozniacki

in lowlight, NEVER use Cine gammas; they steal too much light, beginning in mid-range!

This is misleading; have a careful look at the way the gamma curves process information. If the range of subject brightness (highlight to shadow) is narrow then the STD gammas will be preferable. A church may well have a great range of lighting and there the Cine gammas will be better. There is no reduction in low light capability using the cine gammas.

[Piotr Wozniacki]

Originally Posted by Serena Steuart

This is misleading; have a careful look at the way the gamma curves process information. If the range of subject brightness (highlight to shadow) is narrow then the STD gammas will be preferable. A church may well have a great range of lighting and there the Cine gammas will be better. There is no reduction in low light capability using the cine gammas.

With all due respect, I disagree. Even the most "punchy" cine, i.e. Cine1, starts compressing way earlier than the STD1 curve. You will never get a really (overall) bright picture in lowlight with cine. So unless this is an artistic preference, cine gammas should be avoided indoors (especially churches). In those (rare) occasions of greater range of lighting, it's better to modify Knee.

[Scott Karlins]

Originally Posted by Mervin Langley

Thanks for the information. Here is a clip that I recorded at a wedding last week:

http://langleyvideography.com/Langle...68K_Stream.wmv

Nice clean footage Mervin. What PP did you use? Custom?

Scott K.

[Dominik Seibold]

Originally Posted by Sebastien Thomas

4) dark footage without gain may be better in post than brighter with gain and noise

No. Gain before 8bit-quantization and mpeg2-compression is better than after. Gain doesn't add noise, but amplifies the noise which is already in the video-signal. 8bit-quantization and mpeg2 does add even more noise, so using gain in post means to amplify that noise, too.

[Serena Steuart]

Originally Posted by Piotr Wozniacki

With all due respect, I disagree.

That's OK, I expected you to disagree. One needs to refer to the gamma curves and to define the lighting. My post covered the ground.

[Sebastien Thomas]

Originally Posted by Dominik Seibold

No. Gain before 8bit-quantization and mpeg2-compression is better than after. Gain doesn't add noise, but amplifies the noise which is already in the video-signal. 8bit-quantization and mpeg2 does add even more noise, so using gain in post means to amplify that noise, too.

You can use gain while shooting. +3 is most often OK, more gets dangerous.
Of course, EX1 record in mpeg2. But when editting, you can go to something else, like prores for example, which is 10 bits. Then you can work on your footage. Doing things this way you can also work only on the part of the image needing it, without touching the part which is fine. You can also add filters to soft or remove the noise.

I don't say "shoot underexpose", I just say I would prefer to be slightly underexposed and raise light in post than trying to shoot exposed right by adding a lot of gain.
This is a compromise you have to do on set, but don't be afraid to work that way. Once again, the best thing you can do is practice, practice and... eh... practice.
Also, don't forget to come back here and share your experience :)

[Dominik Seibold]

Originally Posted by Sebastien Thomas

You can use gain while shooting. +3 is most often OK, more gets dangerous.

No. Use as much gain as possible (without clipping). Gain increases the signal-to-noise-ratio, because the other noise-sources after it loose weight. If it gets too light (for example that dark atmosphere is gone) you can reduce brightness in post. That of course will keep the better s/n-ratio.

Originally Posted by Sebastien Thomas

Of course, EX1 record in mpeg2. But when editting, you can go to something else, like prores for example, which is 10 bits.

Converting to ProRes will not undo the mpeg2-compression and 8bit-quantization done before. It just adds even more noise (not much, but there really isn't any advantage doing this).

Originally Posted by Sebastien Thomas

Then you can work on your footage. Doing things this way you can also work only on the part of the image needing it, without touching the part which is fine.

Concerning noise it is always more clever recording with gain and darken the too bright areas (of course they must not be clipped, because that means information-loss) than doing the opposite.

Originally Posted by Sebastien Thomas

You can also add filters to soft or remove the noise.

Also that works better with gain while recording, because then there's less noise to remove.

You really have to think about the signal-path the brightness-information of a pixel goes through and that each component adds some noise. An amplifing component amplifies all the noise added by components before it. So using gain as early as possible means to amplify as less noise as possible. It's all about the signal-to-noise-ratio, not about absolute values.