View Full Version : 12dB grain


Roy Keane
September 23rd, 2007, 10:57 PM
Dear members

The other day I shot a wedding dinner, location was a standard ballroom. My camera setting was "TV 50" and gain was 12dB because of low-light.

The next day, when watching on a LCD 23" (res 1366X768) , the picture look terribly grainy. However when I hooked up the camera to a 14" tube interlaced TV, the grain that appeared on the LCD TV, was almost gone.

1. May I know whether any members have made this same observation

2. Should I shoot with a 12dB gain in low-light position if I know the end-user is going to watch the video using a 40" LCD/plasma tv?

3. Is there a method to remove the grain in post?

Thanks.
Roy

John DeLuca
September 23rd, 2007, 11:07 PM
Try turning the lcd tv's sharpening down a bit. I think you can use alittle blur, but noise is hard remove.......12db isnt that bad. It should be acceptable for a wedding.

Benjamin Hill
September 24th, 2007, 12:15 AM
Higher resolution displays are less forgiving to the HD image and will definitely make issues with focus and grain much more evident.

I always think gain=grain, and try to avoid using it at all. But covering events sometimes requires it, and as John pointed out, for a wedding video some grain can be perfectly acceptable and many people won't even notice it.

I've accidentally kicked on the gain once or twice when I didn't want it, and have never found a filter that could remove it nor minimize it in post.

Mikko Lopponen
September 24th, 2007, 02:04 AM
The next day, when watching on a LCD 23" (res 1366X768) , the picture look terribly grainy. However when I hooked up the camera to a 14" tube interlaced TV, the grain that appeared on the LCD TV, was almost gone.


Simple. LCD's are horrible :)

CRT's have better color and especially contrast so noise will blend better into the blacks. They are also smoother. Some LCD's with poor panels will highlight noise. Be also sure to check your contrast and brightness settings. LCD's tend to do a lot adjustments digitally so raising the contrast will also raise noise.

Winfried Dobbe
September 24th, 2007, 08:17 AM
Also my experience: the higher the resolution, the more visible the noise becomes. On the small A1 LCD display the image always looks perfect....

Did you turn on noise reduction in the camera. NR1 on low reduces noise considerably, while the "ghosting" is hardly visible if the objects don't move too fast.

I tried a lot of filters to remove noise and there are only a few that work well. I have just bought the new DE:noise filter (http://www.revisionfx.com/products/denoise) and that one works usually very good, although it takes quite a lot of render time. I use it for Final Cut, but it's available for several applications.

Back when I was still using Premiere, I once tested something called "neat video", that also worked reasonable.

regards, Winfried

Andrew Waite
September 24th, 2007, 09:30 AM
I too switched from Premiere to FCP, but I too used NEAT VIDEO and I can say it did a fine job of removing noise and grain, it's too bad it's a windows only program.

Jose Ortiz
September 24th, 2007, 11:30 AM
I always end using the gain of 12B on my weddings at the end of the night.
And its true how grainy is at the time of post. TMPGENC is the best for noise removal, at least after trying different softwares. The price of the is good too! Results awesome!

Michael Buonopane
October 5th, 2007, 04:53 AM
Try shooting at 6 db, and then enhancing the gain in post. The acquired image is darker but the end product is cleaner. I had good luck doing this for a wedding.

Steven Dempsey
October 5th, 2007, 10:32 AM
I would also recommend experimenting with your shutter speed. Slowing it down will give you more light...you can find a point where motion blur is not too obvious...

You can also mix and match...slower shutter speed and 6db gain....

But I concur that LCDs are horrible and expose every possible flaw in your video. Depending on which LCD you own, some are known to even introduce their own noise on top of the mix. I own a Gateway HD LCD which I use for my primary monitor and it's horrible to work with. The noise level in it makes me think my footage is terrible but when I view it on my plasma or a CRT it looks beautiful....Aargh.