grain in fall off area

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I was playing around with a three point light setup in a room with some redheads and noticed that there was alot of grain showing in the falloff zones on the walls.
This was exacerbated when the iris was closed down and improved when opened up. But using the spot meter on the camera I had to get it up to 50% in progressive and 40% in interlace to eliminate the grain. This of course blew out the elements in the rest of the picture.
I'm a novice of course, so I assume using a scrim or a black flag to block off some light would help. But have you guys noticed this phenomena of grain in the fall off zones? I dont see it in the pd170. I find grain is a quirk of this camera that I have to learn to deal with.
 
Re: grain in fall off area

Hey,
Yes the noise (call it what it is, not grain) in the 20 to 40 range sucks. I just got done with a feature that shot in a movie theater.

We all think dark is, well dark & blue. This is sure death for the DVX100a. The noise in the blue channel is so overwhelming it is unsettling.

I use Digital Film Tools O Zone to pick the problem area & drop it's value to a darker one. This coupled with a G blur of only the blue channel is a Band Aid for this. But then you recompress to the DV CoDec & poof, noise again.

Be careful with darkness & especially blue darkness.

O-Zone rocks Thou !!

Steve
 
Re: grain in fall off area

What is O-zone? I have never heard about it before. So you can choose an area with a certain light meter reading and then pull it down some more? Sounds like something you can do with a gamma curve correction.
I thought the only way around this is to use more light to the problem area. I think this is where something like dv rack may come in handy when you are shooting with their zebra lines for dark areas.
 
Re: grain in fall off area

This can also be lessened by your in camera settings. Do a search on Grain and the DVX on this forum and you will find some good settings for your camera. Just to start you out, cinegamma has a lot to do with the grain, as well as your matrix settings. I also find it possible to get rid of a lot of grain in post with a simple curves adjustment. Hope this helps.
 
Re: grain in fall off area

Let's also not forget that "night" scenes are always very well-lit. Tell your audience it's night by other visual clues, and they'll believe you when you present them with full-color characters and fire hydrants you can see from 100 yards away . . .

The best cure for noise, of course, is light.

And let's see some stills of the redheads! ::)
 
Re: grain in fall off area

I agree the blue channel is definitely very noisy. I mucked around when I first got the camera in low light and did things like bias the colors towards red to avoid the grain and tune down the black pedestal(crush the blacks) and the detail level. I couldnt for the life of me see what coring did at all.

Yes I got rid of the cine matrix but it didnt make much difference. I have never used any other gamma setting except cine so I may try it. I prefer to do things in pre than post. People have told me to get as clean a picture to work with rather than fixing it in post.

Went out with a one redhead. Never fortunate enough to have three though :)
 
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