PMW 350 Lens, low light, noise etc etc

Steve Phillipps · January 24th, 2010, 11:00 AM

Cool, 1/2 stop sounds more reasonable. I know vaguely the science behind (thanks to a previous post by Alister I think!), and always thought of it as present but minor, just enough to make it worth sticking at 0db unless there is a big reason why not, as there is on the Varicam as it's not as noiseless as the Sonys it seems (from personal observation and comments from others). Actually from my observations on Varicam and PDW700, the Varicam has dynamic range to burn and the 700 is ultra quiet. In fact is's amazing to hear that the PMW350 is even quieter.
Steve

Tom Roper · January 24th, 2010, 11:50 AM

I shoot the standard 709 gamma with knee but the issue I have with 0 db boils down to the fact that the benefit of -3db lower noise is evident in EVERY image (if slight), whereas the benefit of 1/2 stop more latitude will only be evident in high contrast scenes. Using the histogram in combination with 100% zebras gives me the tools to recognize when it would be beneficial to switch to 0 db for the extra latitude, or alternatively preserving the low noise of -3 db for the situations that do not.

Steve Phillipps · January 24th, 2010, 11:53 AM

Tom, I'm absolutely amazed at that. Especially taking into account the comments about how noise free the 350 is even at 6 or 9 db. I never had the slightest hint of noise at 0db in the PDW700 - and I do look!
A real surprising find.
Steve

Tom Roper · January 24th, 2010, 11:58 AM

I will qualify my statement then that the benefit of -3db 'in theory should be' evident in every scene. It's not my intent to mischaracterize or draw comparisons to the PDW700.

It's tough to see noise, it's tough to recognize 1/2 stop of latitude without equipment.

Do you understand my logic? If a scene only has 5 stops of latitude, why not -3 db, whether noise is visible or not?

Alister Chapman · January 24th, 2010, 01:05 PM

It's a valid point that if a scene has restricted latitude then negative gain will give a noise advantage. I guess I'm too used to shooting in challenging conditions and forget that some lucky people get to control their scenes :0)

I would not characterize the PDW-700 as noise free, it's certainly one of the least noisy cameras on the market, but there is still some noise.

Steve Phillipps · January 24th, 2010, 01:20 PM

Quote:

Originally Posted by Tom Roper

Do you understand my logic? If a scene only has 5 stops of latitude, why not -3 db, whether noise is visible or not?

I do understand and it is good logic. I guess coming from a film background I'm diehard in my view that video has terrible latitude and needs all the help it can get! They are a million times better than they used to be though of course. What if you low latitude scene suddenly has a flash of brightness (subject turns towards a light source maybe), I'd prefer to be safe re latitude - as long as there was no noticeable noise penalty (ie noticeable on screen rather than measurable).
Steve

January 24th, 2010, 01:05 PM	#35
Alister Chapman Inner Circle Join Date: Dec 2005 Location: Bracknell, Berkshire, UK Posts: 4,957	It's a valid point that if a scene has restricted latitude then negative gain will give a noise advantage. I guess I'm too used to shooting in challenging conditions and forget that some lucky people get to control their scenes :0) I would not characterize the PDW-700 as noise free, it's certainly one of the least noisy cameras on the market, but there is still some noise. __________________ Alister Chapman, Film-Maker/Stormchaser http://www.xdcam-user.com/alisters-blog/ My XDCAM site and blog. http://www.hurricane-rig.com

January 24th, 2010, 11:00 AM	#31
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	Cool, 1/2 stop sounds more reasonable. I know vaguely the science behind (thanks to a previous post by Alister I think!), and always thought of it as present but minor, just enough to make it worth sticking at 0db unless there is a big reason why not, as there is on the Varicam as it's not as noiseless as the Sonys it seems (from personal observation and comments from others). Actually from my observations on Varicam and PDW700, the Varicam has dynamic range to burn and the 700 is ultra quiet. In fact is's amazing to hear that the PMW350 is even quieter. Steve

January 24th, 2010, 11:50 AM	#32
Tom Roper Trustee Join Date: Jun 2004 Location: Denver, Colorado Posts: 1,891	I shoot the standard 709 gamma with knee but the issue I have with 0 db boils down to the fact that the benefit of -3db lower noise is evident in EVERY image (if slight), whereas the benefit of 1/2 stop more latitude will only be evident in high contrast scenes. Using the histogram in combination with 100% zebras gives me the tools to recognize when it would be beneficial to switch to 0 db for the extra latitude, or alternatively preserving the low noise of -3 db for the situations that do not.

January 24th, 2010, 11:53 AM	#33
Steve Phillipps Inner Circle Join Date: Apr 2006 Location: Wales Posts: 2,130	Tom, I'm absolutely amazed at that. Especially taking into account the comments about how noise free the 350 is even at 6 or 9 db. I never had the slightest hint of noise at 0db in the PDW700 - and I do look! A real surprising find. Steve

January 24th, 2010, 11:58 AM	#34
Tom Roper Trustee Join Date: Jun 2004 Location: Denver, Colorado Posts: 1,891	I will qualify my statement then that the benefit of -3db 'in theory should be' evident in every scene. It's not my intent to mischaracterize or draw comparisons to the PDW700. It's tough to see noise, it's tough to recognize 1/2 stop of latitude without equipment. Do you understand my logic? If a scene only has 5 stops of latitude, why not -3 db, whether noise is visible or not?