grain in blacks in daylight

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i've been shooting with the dvx for nearly 6 months now and I've noticed alot of grain- ie dancing pixels see in extreme low light- in the blacks of men's suits during my wedding shots. This is in full daylight!
My settings are cinegamma v thick, cine matrix and the black pedestal at -2 and detail zero. I heard cine matrix can cause weird colour shifts in low light but honestly getting grain in ordinary daylight is really pissing me off. This is a pal model 100a by the way. I love the images but we get some weird artifacts with some settings. These were extensively discussed before.
Any of you guys have any ideas on why I'm getting grain?
 
Re: grain in blacks in daylight

For me, I notice a lot of noise in navy blue suit coats in otherwise well lit scenes. I'm curious to know myself.
 
Re: grain in blacks in daylight

There are many things that can make your image grainy. The best possible way to get rid of grain is to experiment with your camera. Make individual scene files for individual situations. I have a setting for outdoor (sun) and for indoor (sun). I also have a setting for when I am using lights indoors and outdoors. These are all 24pA settings, the only differences are the chroma, master ped, gamma settings, detail coring, and matrix settings. I have found that the things that effect the "grain" the most are the matrix settings and the level of your chroma. Another thing that can greatly effect the grain of a picture is your white balance. Having an incorrectly ballenced WB will give you those really noisy blue and red colors. These colors will also get noisy if they are over saturated. I have found that the DVX produces extremely saturated colors, so I have reduced the chroma level significantly, and rarely do I experience noise in dark areas, and especially not when in well lit areas. Just for an example, here are my settings for my "outdoor sun".

detail level -2
v detail level -2
detail coring +7
chroma level -4
chroma phase 0
color temp 0
master ped -4
gamma_cine-like
Matrix-Norm
skin tone DTL-off
V detail freq THin
Progressive 24p (ADV)

I have gone through many tests in the outdoors, and have found that these settings give the perfect balance (for me) of saturation and overall tonal range. These settings are of corse a general for me, and I may tweek them slightly in the field when working in different locations and differnt times of the day. Try it out, see what you get. It is easy to get additional grain with this camera, but remember, that it is almost impossible to properly see your scene through the viewfinder or the LCD. Even after I have tried to callibrate, as close as possible to my NTSC monitor, the LCD is still a bit off.
 
Re: grain in blacks in daylight

Yes, I've had lots of trouble with color "grain" - in fairly big, squarish patches, especially in wood-tones.  I've found no general solution... just to tweak with a monitor whenever possible. The LCD doesn't show these artifacts, in general.

I have a 100P - can anyone (Stefan?) tell me if the Detail Coring on the A makes a big difference, and if how big the drawbacks are? I often have to pay a high cost by lowering detail level more than I'd want to in order to get rid of graininess in wood tones... and since most of what I do is classical music videos, almost everything has lots of wood and no control over lighing...
 
Re: grain in blacks in daylight

Detail coring is supposed to take the excess image detail, such as grain and discard it.  You should try and set it up so that you have the maximaum image detail with the least amount of grain.  Unfortunatly, I have found this hard to do, as it is very hard to see the difference with the naked eye.  In performing some experiments, however, I have noticed that the viewfinder/ LCD shows a lot more grain then when i capture it to my computer or play it on a tv.  I don't know why this is, but to anyone that seems freeked out about what they see in the LCD, trust me, many things look better once viewed on something else.
 
Re: grain in blacks in daylight

Two big things:
1) Manual or Preset White Balance (Auto is Noisy!)
2) 0IRE not 7.5IRE !
That made a huge difference for me, when analyzing footage using Blue Gun on an 800 Line PVM monitor
FWIW

Brian
 
Re: grain in blacks in daylight

Last Friday I was at the dvx to 35 blow up sceening in LA where I met someone who seems to have an answer to your question. I think his name is Kevin and is a dvxuser member.

Apparently he did some noise tests with the camera and discovered that the camera has the best signal to noise ratio in tungsten scenarios. In daylight shooting circumstances, somehow a sizable chunk of information is thrown out, causing your frustrating noise.

His solution is to use an 85 filter (the orange one) and white balance DIRECTLY THROUGH it for daylight shooting conditions. According to his tests, the lost information is reclaimed.

I asked him if he would be posting his findings here at the forum. He said that with some time to complile the images, he may.

It might be worth your while to borrow or rent an 85 to see if it make a difference for your shooting needs.

Good luck!

Edber
 
Re: grain in blacks in daylight

Have to have a closer look but I have not noticed any visible grain when I've shot in daylight.
 
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