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Colour correction filters

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Reading the thread on HD and the poor performance of cc filters,and with a current thread on another forum allso coming down against there use (with still cameras) what is the overall view today?

I use a Panasonic 3 chip NV-400 and utilize both Urpro filter and WB at all depths (to 40mtrs).I have tried both filter only and WB only but my results have allways been best using both at the same time.My film does not suffer loss of brightness and even low light/overhangs do not seem compromised.I do admit the Pany does have a trick up it's sleeve in the shape of a seperate WB sensor (ie. it does not set WB through the lens).This allows me to fit a piece of pure white card inside my housing and infront of the sensor.Setting the cam on automatic WB then means the balance is corrected every time I power up and allways in reference to the card, and irrespective of depth.

So, are cc filters worthwhile or "The spawn of the Devil"?

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I want one of those separate sensors in my A1..

 

Bugger...

 

Dive safe

 

DeanB

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On the Sony HDV cams (HC1 and A1), there appears to be a significant difference between auto white-balance and manual (one push) white-balance (one push is much better). I suspect that the filter is needed only for auto white-balance. However, I don't really have a clue ;) . The white-balance ability of the HC1/A1 seems to be better than norm.

 

--Mark

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Color correction filters are absolutely necessary for correct and vibrant colors in underwater video unless you are shooting either macro, at night, or in dark or murky water, all while using lights. White balancing on a white card inside your housing with a Panasonic 3 chip NV-400 would not correct for various lighting conditions while diving. The reason for manual white balancing is to tell the camera what is the value of white. Camera sensors do not see color, they only see the lumiance values of black to white, through either a Beyer Filter (1-chip), or through three discrete sensors (3-chip) each seeing only the red, blue or green parts of the image separated by a prism. The value of white varies dependant on depth, visability, distance, angle, color temperature of the light source, and other factors. Once the camera knows what is white, it will then be able to calculate accurate values for all of the colors. Color correction filters work by blocking a percentage of the short wavelength light (mostly blue then green) and allow the longer wavelength light (red then orange) to pass through. The deeper you go, the less color corrected light that your camera will see, so low lux performance is very important, especially the deeper you go. I shoot with a Sony FX1 in a Bluefin HD housing, and always shoot with a color correction filter during the day, and get outstanding color in my videos. I use lights only at night, or if in a dark overhead environment. Nothing beats the natural light of the sun, manually white balanced through a color correction filter for underwater video. Also, it is usually necessary to manually white balance often, due to changing conditions and depths

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White balancing on a white card inside your housing with a Panasonic 3 chip NV-400 would not correct for various lighting  conditions while diving.

Maybe he's got a clear housing like an Ikelite. Or maybe enough light is coming in through the port, windows etc.?

 

Nick

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Bang on right,I use a SeaPro housing, effectivly an 8" alluminium tube with 1/2" perspex each end.The interior of the case is therefore allmost as well lit as exterior.I did confirm that I had allso reached the conclusion that permanent use (excluding night diving with lights) of a red filter does seem to give the best results, especially when combined with WB balance.Obviously us video users,who seem to all sing the praises of such filters are very different from our stills bretheren who seem to dislike them intensly.Why???

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