Noisey Video at DVinfo.net

Geoff Schatzel · March 26th, 2009, 10:57 PM

I know the Z7 is better in low light than the Z1, but at 18db gain the video is very grainy. Anyone have some feedback on how to better handle this? I do a lot of weddings and running a top light doesn't work in every situation.

Adam Haro · March 26th, 2009, 11:08 PM

Checkout neatvideo.com takes forever to render but it definitely cleans up noisy footage.

Greg Laves · March 27th, 2009, 07:05 PM

I don't care for the blown out, too much on camera light kind of look. But the Z7 shoots really well in low light when compared to any other comparable HDV camcorders. So it really shouldn't take very much extra illumination to be able to get away from the 18 db gain setting. I have an old NRG Vari-Light which is very easy to control and doesn't look too harsh. And you could always add extra diffusion if you felt you needed it. But I never have felt like I needed it. Another alternative to 18 db gain would be to go to 1/30 sec shutter speed which will brighten the shot up a lot. BUT you have to be careful not to have too much camera movement or you can get some motion blurring artifacts.

Robert Bec · March 28th, 2009, 07:32 PM

Quote:

Originally Posted by Geoff Schatzel

I know the Z7 is better in low light than the Z1, but at 18db gain the video is very grainy. Anyone have some feedback on how to better handle this? I do a lot of weddings and running a top light doesn't work in every situation.

18db of course your going to get grain. I also do heaps of weddings and i dont go over 6db with a 10watt on camera light

Wacharapong Chiowanich · March 28th, 2009, 09:27 PM

What are your final deliveries to your clients Geoff? If they are one of the HD flavors, I agree there is a cause for concern. If they are, let's say PAL or NTSC SD DVDs or one of the formats with comparable frame sizes such as VGA or 960x540, the noises will be less obvious. How less and whether the videos will look acceptable depend to a large extent on how far the downscaling is done.

I remember outputting to a PAL DVD downscaled from the original footage in 1080/50i HDV shot on Sony FX1 at 18dB gain. Though the image looked quite horrible, as expected, in both FCP and the Quicktime Player, by the time it was downconverted to an Mpeg-2 PAL DVD, the noises were almost unnoticeable. Everyone who saw the video was happy. And the same video reduced to an iPhone-compatible format, H.264 480x270 at 25fps, looked practically perfect.

I'm sure your Z7 will do a lot better than my FX1 so go ahead and shoot. You could try adding some low-powered light (up to 10w maybe with a soft diffuser) if the noise issue still bothers you.

Wacharapong

Geoff Schatzel · March 30th, 2009, 06:10 AM

I shoot in PAL. And have lowered the shutter to 1/25 to get the extra light. I am in the process of purchasing a light that isn't so "spotlight - ish." It's a 10W PAG light and should do the trick.

I do edit in High Def, but output in SD Mpeg2. So maybe you are right and it wouldn't look so pronounced.

I use Canopus Edius for editing and someone on their forum talking about using the "motion blue" filter in post production up to a value of 30 to get rid of some of the noise. I would like to get away from 18db and use up to 9. I think this new light will do the trick.

Thanks for the info guys! Much appreciated.

Zach Love · March 31st, 2009, 07:24 AM

You could also try to get a stronger light, mount it on the back of the handle and add diffusion or a mini softbox to the light. That would dim the light, widden the spread of light and soften the shadows.

You don't want to have a slower shutter than frame rate, so I would also say only go 1/25 if shooting progressive. Interlace is 2x the frame rate... ie NTSC is 30fps = 60 fields = 1/60 shutter, PAL is 25fps = 50 fields = 1/50 shutter. If shooting progressive then 24p = 1/24 shutter, or 25p = 1/25 shutter, or 30p = 1/30 shutter.

Although the standard frame rate for film is 1/48, but that is mostly because it takes time for the camera to physically move the film to the next frame. Thus film cameras use 1/48 of a second to position the next negative, 1/48 of a second to expose. Video cameras aren't moving the chip, so there is no down time that you have to wait for.

March 26th, 2009, 10:57 PM	#1
Geoff Schatzel Regular Crew Join Date: Feb 2009 Location: Gold Coast, Australia Posts: 33	Noisy Video I know the Z7 is better in low light than the Z1, but at 18db gain the video is very grainy. Anyone have some feedback on how to better handle this? I do a lot of weddings and running a top light doesn't work in every situation. Last edited by Geoff Schatzel; March 26th, 2009 at 11:54 PM.

March 26th, 2009, 11:08 PM	#2
Adam Haro Regular Crew Join Date: Aug 2008 Location: Fresno, CA Posts: 171	Checkout neatvideo.com takes forever to render but it definitely cleans up noisy footage.

March 27th, 2009, 07:05 PM	#3
Greg Laves Major Player Join Date: Nov 2007 Location: Corpus Christi, TX Posts: 640	I don't care for the blown out, too much on camera light kind of look. But the Z7 shoots really well in low light when compared to any other comparable HDV camcorders. So it really shouldn't take very much extra illumination to be able to get away from the 18 db gain setting. I have an old NRG Vari-Light which is very easy to control and doesn't look too harsh. And you could always add extra diffusion if you felt you needed it. But I never have felt like I needed it. Another alternative to 18 db gain would be to go to 1/30 sec shutter speed which will brighten the shot up a lot. BUT you have to be careful not to have too much camera movement or you can get some motion blurring artifacts.

March 28th, 2009, 09:27 PM	#5
Wacharapong Chiowanich Major Player Join Date: May 2008 Location: Bangkok, Thailand Posts: 400	What are your final deliveries to your clients Geoff? If they are one of the HD flavors, I agree there is a cause for concern. If they are, let's say PAL or NTSC SD DVDs or one of the formats with comparable frame sizes such as VGA or 960x540, the noises will be less obvious. How less and whether the videos will look acceptable depend to a large extent on how far the downscaling is done. I remember outputting to a PAL DVD downscaled from the original footage in 1080/50i HDV shot on Sony FX1 at 18dB gain. Though the image looked quite horrible, as expected, in both FCP and the Quicktime Player, by the time it was downconverted to an Mpeg-2 PAL DVD, the noises were almost unnoticeable. Everyone who saw the video was happy. And the same video reduced to an iPhone-compatible format, H.264 480x270 at 25fps, looked practically perfect. I'm sure your Z7 will do a lot better than my FX1 so go ahead and shoot. You could try adding some low-powered light (up to 10w maybe with a soft diffuser) if the noise issue still bothers you. Wacharapong

March 30th, 2009, 06:10 AM	#6
Geoff Schatzel Regular Crew Join Date: Feb 2009 Location: Gold Coast, Australia Posts: 33	I shoot in PAL. And have lowered the shutter to 1/25 to get the extra light. I am in the process of purchasing a light that isn't so "spotlight - ish." It's a 10W PAG light and should do the trick. I do edit in High Def, but output in SD Mpeg2. So maybe you are right and it wouldn't look so pronounced. I use Canopus Edius for editing and someone on their forum talking about using the "motion blue" filter in post production up to a value of 30 to get rid of some of the noise. I would like to get away from 18db and use up to 9. I think this new light will do the trick. Thanks for the info guys! Much appreciated.

March 31st, 2009, 07:24 AM	#7
Zach Love Major Player Join Date: Jul 2006 Location: Chicago, IL Posts: 944	You could also try to get a stronger light, mount it on the back of the handle and add diffusion or a mini softbox to the light. That would dim the light, widden the spread of light and soften the shadows. You don't want to have a slower shutter than frame rate, so I would also say only go 1/25 if shooting progressive. Interlace is 2x the frame rate... ie NTSC is 30fps = 60 fields = 1/60 shutter, PAL is 25fps = 50 fields = 1/50 shutter. If shooting progressive then 24p = 1/24 shutter, or 25p = 1/25 shutter, or 30p = 1/30 shutter. Although the standard frame rate for film is 1/48, but that is mostly because it takes time for the camera to physically move the film to the next frame. Thus film cameras use 1/48 of a second to position the next negative, 1/48 of a second to expose. Video cameras aren't moving the chip, so there is no down time that you have to wait for.