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Grain or prominent pixels? Help!


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#1 Michael Garcia

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Posted 06 March 2007 - 05:06 PM

I looked through this forum and didn't see any problems described that are like mine so I am going to go ahead and throw down my first post. (please excuse me if I missed it though!)

I recently shot a feature on the HVX using the P2 cards and everything seemed to be going great until last week when I received a call from my producer. They brought me in and I saw some footage that I can only describe as grainy. Several scenes, when blown up to full monitor size had a whole lot of movement going on. It looked as though I had under exposed 16mm film and blew it up huge. Now the main thing is that I don't see any direct correlation between lighting situations or camera gags. some shots are in bright sunlight out in a park, using a ND .9 and a polarizer and stopped down considerably, and others are in a night club scene, clean lens and WFO. but there is no consistency. it is not all of the scenes outside nor all of the low light scenes. All of my external components remained the same for those enviornments and I don't know what I must of changed, possibly in camera, to cause this problem? And I have also considered did I cause this problem? could something like this happen in a bad import to an avid or other non-lin editing equipment?

Well I hope I specified my problem clearly and I thank those of you who may be able to help me with this issue!
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#2 Michael Nash

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Posted 06 March 2007 - 05:49 PM

Could the gain switch have gotten bumped accidentally between setups? It happens frequently with the design of this camera. Some people program all the gain switch positions to be 0db to prevent this.
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#3 Daniel Sheehy

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Posted 06 March 2007 - 09:57 PM

Doesn't the HVX record camera settings in the meta-data with the footage?
You might be able to check the gain settings that way... because that does sound like the most likely scenario.
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#4 Michael Garcia

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Posted 07 March 2007 - 06:59 PM

Ok I will check that out, thank you both very much for the info I appreciate it!
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#5 Ken Minehan

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Posted 19 March 2007 - 10:07 PM

It really sounds like the Gain was on. chances are if the grain is very apparent it would have been Db 6 or 9. I have made that mistake before too. I feel this is a design flaw for the P2 camera. The gain button is in a place where it is easily bumped when moving around. So what i do now is, as Mr. Nash suggests, to set all the gain settings to 0. But sometimes i like to set one to -3 db. One of my CA from before has also blue tacked the switch so it doesn't get bumped.

In post there is a noise/grain reducer. It may help a little bit, but you will still see most of the grain.

Regards
Ken Minehan
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#6 Chad Stockfleth

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Posted 26 March 2007 - 06:47 PM

Were you using a monitor? You can usually tell from the LCD when gain is boosted. Not something to let slip past.
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#7 Michael Garcia

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Posted 27 March 2007 - 02:47 PM

Were you using a monitor? You can usually tell from the LCD when gain is boosted. Not something to let slip past.

Yes I was Using a17" HD monitor, plus the on board while operating, and their was no indication of Gain boost during setup or shooting. But doesn't the Signal Bypass the P2 card and any modifications, just like a pass through when it runs out to Monitor? The grain is very Prominent currently, and When we were shooting there was no appearance of this pixelation on the Monitor, Not that things doen't occasionally slip through the cracks, but I was all over the camera and monitor, My Director and Producers were there 99% of the time as well and they are well versed in Video and Hi-Def and they noticed no Gain Spike during primary photography. So I am still currently stumped as to where my mistake lies. Thank you all for the help though!
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#8 matt guest

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Posted 30 March 2007 - 08:05 PM

Yes I was Using a17" HD monitor, plus the on board while operating, and their was no indication of Gain boost during setup or shooting. But doesn't the Signal Bypass the P2 card and any modifications, just like a pass through when it runs out to Monitor? The grain is very Prominent currently, and When we were shooting there was no appearance of this pixelation on the Monitor, Not that things doen't occasionally slip through the cracks, but I was all over the camera and monitor, My Director and Producers were there 99% of the time as well and they are well versed in Video and Hi-Def and they noticed no Gain Spike during primary photography. So I am still currently stumped as to where my mistake lies. Thank you all for the help though!

Hi Michael,
A guy who shoots underwater has been having similar problems

http://wetpixel.com/...lues,and,blacks
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Media Blackout - Custom Cables and AKS

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Ritter Battery

Visual Products

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Glidecam

FJS International, LLC

Opal

Aerial Filmworks

The Slider

Technodolly

Abel Cine

Rig Wheels Passport