richmondfloyd
Active member
And what is the maximum gain you would use to maintain a good DVD quality using the EX1?
Thanks
Thanks
Is it better to use a high gain or colour grade after when filming in a dark venue?
- Thread starter richmondfloyd
- Start date
Analog gain is almost always better than trying to pull detail out of a dark scene in lossy compression. Crank it up to get a good exposure. Noise removal in After Effects can fix sensor noise.
MadHMC150
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Barry_Green
Moderator
The very very best way is to make sure that the camera has enough light to work with. If there's any way possible to convince the venue to bring up the overall lighting level, it will do far more for you than any amount of post-manipulation or gain ever could.
Once that option's off the table, you then have to work with what you've got -- and the first and foremost thing to do is make sure that you're getting as much light into the camera as you can. Make sure the ND filters are off and the iris is wide open. After that, you can consider whether the smeariness of going to 1/24 shutter (assuming you're shooting 24p) is worth it. Going to 1/24 will double the amount of light coming into the sensors, without increasing noise. That's about as far as you can push it, without getting additional light in.
Gain is an after-the-fact electronic amplification of the signal. Sometimes it's awful, but in small quantities it might do what you need.
If you're willing to run the footage through Neat Video in post, Neat can really vacuum up a tremendous amount of noise. If I knew for a fact that I was going to have to shoot in a very dark environment, I might gamble on using gain with the idea that Neat will take care of much (if not all) of the noise problem.
I'm not a fan of bringing footage up in post, especially when recorded on an 8-bit codec. You'll get nasty blocky compression artifacts and serious gradient banding issues if you try to bring it up too far.
Now, the ultimate answer here is for you to run some tests now, so you can figure out what you prefer and what your workflow should be. Take the camera into a dark environment and then try the various techniques. You may hit upon something that works for you.
Once that option's off the table, you then have to work with what you've got -- and the first and foremost thing to do is make sure that you're getting as much light into the camera as you can. Make sure the ND filters are off and the iris is wide open. After that, you can consider whether the smeariness of going to 1/24 shutter (assuming you're shooting 24p) is worth it. Going to 1/24 will double the amount of light coming into the sensors, without increasing noise. That's about as far as you can push it, without getting additional light in.
Gain is an after-the-fact electronic amplification of the signal. Sometimes it's awful, but in small quantities it might do what you need.
If you're willing to run the footage through Neat Video in post, Neat can really vacuum up a tremendous amount of noise. If I knew for a fact that I was going to have to shoot in a very dark environment, I might gamble on using gain with the idea that Neat will take care of much (if not all) of the noise problem.
I'm not a fan of bringing footage up in post, especially when recorded on an 8-bit codec. You'll get nasty blocky compression artifacts and serious gradient banding issues if you try to bring it up too far.
Now, the ultimate answer here is for you to run some tests now, so you can figure out what you prefer and what your workflow should be. Take the camera into a dark environment and then try the various techniques. You may hit upon something that works for you.
adamr316
Well-known member
It depends on which recording mode you're in. At 1080/24p in the CINE gamma modes 18dB doesn't look "too bad". But in 1080/60i you're asking for trouble...nothing higher than 9dB please. If in STD modes I would use less...9dB being the most I want to get away with. But STD gamma modes tend to appear brighter anyway so it's OK. Just do some tests to see how much noise you can tolerate.
basspig
Veteran
You guys are being generous. 
I start to find noise objectionable at +3dB. Nowadays, I shoot exclusively at -3dB and only go to 0dB when things are difficult. For night city shots, concerts, stage performances, I never go above -3dB or the highlights get clipped and colors oversaturated into chroma clipping.
I always have a good laugh when I look at big budget Blu-ray concert videos like my wife's U2 "360" Blu-ray, where the cam ops pushed the gain so high that there is grain everywhere and the performers on stage have severe loss of detail due to extreme chroma and hilights clipping. The disc could have looked so much better if they'd shot at 0dB and not worried about the (misleading) viewfinder image.
Lately, I've shot a number of stage productions with black out backgrounds, and even at -3dB, I can still make out the black curtains backstage, while the performers are in perfect exposure with no lost details.
I start to find noise objectionable at +3dB. Nowadays, I shoot exclusively at -3dB and only go to 0dB when things are difficult. For night city shots, concerts, stage performances, I never go above -3dB or the highlights get clipped and colors oversaturated into chroma clipping.I always have a good laugh when I look at big budget Blu-ray concert videos like my wife's U2 "360" Blu-ray, where the cam ops pushed the gain so high that there is grain everywhere and the performers on stage have severe loss of detail due to extreme chroma and hilights clipping. The disc could have looked so much better if they'd shot at 0dB and not worried about the (misleading) viewfinder image.
Lately, I've shot a number of stage productions with black out backgrounds, and even at -3dB, I can still make out the black curtains backstage, while the performers are in perfect exposure with no lost details.
adamr316
Well-known member
You guys are being generous.
I always have a good laugh when I look at big budget Blu-ray concert videos like my wife's U2 "360" Blu-ray, where the cam ops pushed the gain so high that there is grain everywhere and the performers on stage have severe loss of detail due to extreme chroma and hilights clipping. The disc could have looked so much better if they'd shot at 0dB and not worried about the (misleading) viewfinder image.
Lately, I've shot a number of stage productions with black out backgrounds, and even at -3dB, I can still make out the black curtains backstage, while the performers are in perfect exposure with no lost details.
Jeez, I would laugh too. If you have stage lighting and are gaining up you are doing something wrong. What do these guys have a 1/64 ND filter over their lenses? I understand audience shots having gain but noise on the performers? That GD ridiculous!
weismangroup
Active member
Does -3db actually affect the noise? My understanding from Aliister Chapman and others was that it reduces the sensitivity of the camera by 1 stop, and clips the whites at 92, but does not really affect the noise level.
It's discussed in this thread, http://forums.creativecow.net/thread/142/868733#868754, and also there was an article on Video Coalition that I can't put my finger on just now.
It's discussed in this thread, http://forums.creativecow.net/thread/142/868733#868754, and also there was an article on Video Coalition that I can't put my finger on just now.
basspig
Veteran
I think it helps. On CINE2, I see 98% whites in Premiere's scopes. That's just perfect for DVD and broadcast because Premiere can't respect the Fast Color Corrector levels above 100% through to the Median Encoder anyway, so it relieves me of having to render out to uncompressed with the 109 -> 100 adjustment and then render again to DVD or BD. I don't see ANY noise at all at -3dB, and I can pull up the shadows a decent amount (well not as much as I can with Nikon RAW images, but enough to make modest adjustments) in the 8-bit MPEG2 that is written to SxS.