picture quality question

[cakewalkr7]

Since I got my hv20 and started coming here I've been seeing some very high quality video. Today I was playing with the HDV setting and after a ton of hassles, I finally got Premiere to capture. I had two questions.

1. The quality of my video is very noisy (as seen in my screen grab) and doesn't have a lot of sharp detail. Is it due to light or something else? I know without knowing my settings, that may be a tough question to answer, but I'm still kind of noobish and not sure what settings affect this. Right now I've got it on HDV 24p with the TV shutter priority selected and manual white balance. I've had a lot of difficulty selecting the shutter speed and right now I don't have any numbers showing up to the right of the TV option. Can someone explain exactly what steps to take to edit this value?

2. We have to do some greenscreen footage and when I recorded some in DV mode, no matter how I backlit the subject and evenly lit the screen, I still had a good amount of fringe bleed. I thought that if I shot it in HDV, I'd have more edge pixels to work with and might get a cleaner key. Does this make sense or won't it really matter much?

Thanks.

[white_2kgt]

Just about any kind of camera (HV20 included) it needs LOTS of light. I have several 100watt aux lights I setup and bounce off the ceiling of our living room, I notice grain when I don't set them up, makes a BIG difference. The HV20 is MUCH better about this than the ZR60 I had though.

[cakewalkr7]

Thanks. I recorded some footage last night of a small club setting and although the lighting worked out fine, the video was extremely pixelated. I had the camera back about 20 feet from the stage in order to be able to get the whole stage. I was using 24p and the sunset setting as that seemed to give the best auto results for the lighting. I didn't have anything white to white balance it against and it was a last minute setup, so I opted for the auto setting. But, I don't think that would cause the pixelation.... would it? Or is there something else I could check that could cause this? Thanks.

[kevinmeyer]

When I first powered up my HV20 in the evening at home, I was also quite shocked by the noisy image (low lighting at home) - camera set to auto.

during the day with good lighting all was OK!

I believe the noise is caused when the camera kicks in the gain in low light settings.

I haven't had much more time to play around in the low light again but i believe setting the camera manually (trying not to get the gain to kick in) will improve the quality.

Maybe some of the more knowledgable on the forum can give some details on how they set their cameras up in low light to keep noise levels to a min.

[Erik Bien]

The big problem with shooting chroma key with DV (or HDV) is the chroma compression. The "best" solution is to shoot the greenscreen stuff with the camera tethered to a computer with a Blackmagic Intensity HDMI capture card using a codec like Cineform's so you end up with 4:2:2 compression (there's a very clear explanation of the process here).

Recording to tape, you'll get better composites if you shoot in HD but deliver in SD. Another trick people use is to shoot keys with the camera tilted 90 degrees, so the width of the picture becomes the length (obviously this only works if you're keying something fairly vertical to begin with, like a person).

[24Peter]

2. We have to do some greenscreen footage and when I recorded some in DV mode, no matter how I backlit the subject and evenly lit the screen, I still had a good amount of fringe bleed. I thought that if I shot it in HDV, I'd have more edge pixels to work with and might get a cleaner key. Does this make sense or won't it really matter much?

Thanks.

In some preliminary testing, I pulled some very acceptable keys in Vegas using HV20 24p footage. And I didn't even light the scene (it was lit with pretty even daylight streaming in on three sides from windows.) The big difference in edge bleed was how close my subject was to the backdrop. Even a small amount of reflected light off the backdrop was enough to mess up my edges. I know you said you backlit your subject (which is usually very helpful in avoiding the spill effect) but maybe reflected light is part of your problem? Maybe turn down the light on the backdrop?

[joe12south]

Consider shooting in Cine-mode, not shutter priority. Turn off all of the picture processing (color, sharpness, etc.) The camera will try to use the aperture as much as possible, and will try to keep the shutter at 1/48th and avoid gain.

Not only does this yield the most natural, realistic image, but the least noise.

And, yes, more light is almost always the answer!

[joe12south]

re: greenscreen

You can also use a chroma upscaler (like in Nattress) the get cleaner edges from HDV. If possible, the very best choice is to go straight into your computer via HDMI and avoid the HDV compression in the first place.