What are acceptable brightness levels?

[Gregory Lee]

Here is a screenshot of video shot in low light conditions with an HMC-150. I had an on-camera light which was set fairly dim because I did not want to be intrusive. But the camera was at 0 db gain and the waveform monitor shows about 10%.

https://plus.google.com/photos/10479...93092007778674

In Vegas, I adjusted the brightness/contrast levels which helped a bit:

https://plus.google.com/photos/10479...93097062708610

But should I have done the 'gain' in-camera? Or is my original footage bright enough?

[Oren Arieli]

There might be differing opinions. But mine is to capture all the photons during production, rather than try to create new ones in post. Noisy images (due to high gain) can be cleaned up to a certain extent. Boosting levels on a compressed signal will rarely yield good results and would probably be harder to clean up with software like Neat Video - best noise reduction for digital video

[Chris Harding]

Hi Gregory

Remember people will watch your video on screens that are over bright and screens that are also not too bright..it's all their choice!!! Personally I try to use my zebras to get my skin tones nicely exposed in the camera but I have found that you can definately treak a bit in post. The secret is to not just increase brightness but also contrast if you have to do it.

However it's probably better to get it right at camera level most of the time!!

Chris

[John Wiley]

Gergory, for some reason I can't see the images to give specific advice but I can speak generally.

When I was learning video, one of the first things that was drilled into me by other shooters was never to use gain. I stuck to that rule for quite a while. Then I started shooting weddings and that went out the window.

Do not be afraid to shoot with some gain at dark receptions. I've not used the HMC-150 too much but my guess is it would be acceptable up to 15db, assuming you are getting correct exposure. Yes, you will get some noise, but you will get a decent exposure which will easier to correct in post. There are all sorts of tricks you can use in post to reduce noise (crush the blacks, diffusion/glow to smooth out noise in the highlights, vignette to hide dark noise corners, noise reduction, reduce saturation to hide colour noise, etc) but if you have a dark image to start with, there is not a whole lot you can do.

[Chris Harding]

According to the experts and providing you are using zebras, getting just a few zebras on the talent's face at 65% it supposed to be just right for skin tone exposure...I prefer it a bit higher but in all cases, zebras do help a lot to get your exposure correct!!!

Chris

[Gregory Lee]

Here is a different link to the same screenshots:

Index of /temp/screenshot

The HMC-150 goes up to 12 db gain but I was trying to avoid using it. I think I regret it though. I was able to brighten it in Vegas, but will try the gain next time.

Originally Posted by John Wiley

Gergory, for some reason I can't see the images to give specific advice but I can speak generally.

When I was learning video, one of the first things that was drilled into me by other shooters was never to use gain. I stuck to that rule for quite a while. Then I started shooting weddings and that went out the window.

Do not be afraid to shoot with some gain at dark receptions. I've not used the HMC-150 too much but my guess is it would be acceptable up to 15db, assuming you are getting correct exposure. Yes, you will get some noise, but you will get a decent exposure which will easier to correct in post. There are all sorts of tricks you can use in post to reduce noise (crush the blacks, diffusion/glow to smooth out noise in the highlights, vignette to hide dark noise corners, noise reduction, reduce saturation to hide colour noise, etc) but if you have a dark image to start with, there is not a whole lot you can do.

[Steve Slattery]

Without question use the gain to get a decent image, it will be easier to get a decent image in very low light situations. Generally I apply colour curves to improve colours and crush some of the noise.

Steve

[Cole McDonald]

Skin at ~60% to ~85% depending on brightness of the skin (melatonin enhanced vs. melatonin lite) is considered "correct" exposure.

[Bruce Watson]

Originally Posted by Gregory Lee

...should I have done the 'gain' in-camera? Or is my original footage bright enough?

Your original footage is not at all "bright enough". Indeed, it looks starved. The camera is clearly starved of light which is why the resulting picture looks so thin and lacking in color. Not to mention noisy. The entire image is in the shadow end of the spectrum except for the far off window and the reflections off the table and the floor -- and those bright things are far and away the biggest draw for the eyes. Is this what you want -- for people to first look at that window, then the reflections? Somehow I doubt it.

The way I was taught is to get the exposure right in camera, then adjust it as needed in post. You can desaturate a normal image in post, and push all the tones down (crushing the blacks as you go) to create this "dark and moody" look without much problem, without the result looking thin and starved. This is because all you are doing is throwing away information. But thanks to your new and improved capture, you now have the information to throw away.

But it's much much more difficult to do the reverse as you are attempting to do. You can't easily pull this exposure up -- you didn't capture sufficient information -- for example, there's very little detail in the shirt on the guy on the left. If you bring his shirt up to, say, 30 IRE, all you get is a gray blob without texture. Because you didn't capture any texture information. It's much more difficult to "recreate" the missing texture information in post. Same with hue and saturation.

Turning up the gain will make an improvement, but it will only get you so far. Light is what makes video work. And IMHO, you need more light here.

[Chris Harding]

Hi Bruce

Very good point!! A lot of people expect cameras to see in impossible places and forget that they are light hungry. Venues are seldom lit brightly as well. I know an on camera light doesn't exactly flatter the talent but at wedding receptions the first thing I do at sunset is put a light on the camera and I use it too.

The bottom line is that if you have to crank up gain more than about 15db then you seriously need, as Bruce says, the essential ingredient called light ..don't afraid to use it!!!

Chris

[Nigel Barker]

I used to abhor video lights & as we shoot predominantly with Canon 5DIIs thought that we didn't need to add any as we can crank the ISO (gain) right up & as long as the image is correctly exposed it is really noise free. However my eyes were opened a few months ago when we filmed a big Jewish wedding where the photographer didn't use a flash but had a guy follow him round with a Lowel i-light on a pole. This has a 50W halogen car headlamp bulb & throws a decent amount of light which made a fabulous difference to our footage. We have now taken to grabbing a 160-LED lamp to light up the scene as often as possible. Now if only we could charge as much as that top end photographer & afford to have a guy with a Lowel i-light on a pole follow us round all night:-)

[Chris Medico]

There are several recommendations for skin tone here but the jist is to get them up into the center of the exposure curve. Your footage is way too dark.

Try to keep skintone highlights BELOW the knee setting in your camera. Compression of highlights on skin is one of the reasons people can look like they have a plastic faces.

Even if you are shooting a night scene get faces up in the 50 IRE range.

Personally I aim for 40-70 IRE on skin depending on complexion (in the HD world). In the SD/analog world it was more typical to go 50-85 IRE.

[Seth Bloombaum]

Lots of great comments in this thread.

As a general practice, when I get my hands on a new camera I put it through it's paces and work towards two consistent settings, one setting for well-lit, and one for low-light.

As part of the testing, I want to know just how much grain the camera produces at various gain settings. One camera might show zero perceptible grain at +6db, the next maybe at +12db, whatever. I want to know in advance that if I go to 12 or 15 what effect it will have on the image. Then I'm prepared to make a good decision in shooting, knowing what the consequences are.

I've never used the HMC-150, but that would be my first step. Next would be exposure for skin-tones using histogram and zebras, good guidance on that in this thread. If I can't quite get bright enough with acceptable gain and iris & shutter speed, I want to make sure I'm close enough that I can make up the difference in post with acceptable image quality. If not, there's really no other choice than lighting or a new cam that does better with low light!

[Gregory Lee]

Thanks for all the replies!