Led lights + filter for natural light?

[Rafael Lopes]

Hi guys,

I´m going to start a small personal project soon and the 2 main characters are always seated next to this big window. I really would like using the natural light that comes from it, but as the light moves I was thinking of getting one of those cheap led lights that come with a natural light filter. Do you guys think it could work?

thanks in advance

Rafa

[Paul R Johnson]

Nope! An LED v the sun? It may work when the sun is low in the sky and weak, but there is a reason people use HMI to try to outdo daylight. I suspect you may see some of it's light, but a big window will be a predominant light source.

[Rafael Lopes]

I forgot to say that the light that comes from the window is partially bounced from another building, giving it a more neutral whitish tone. Would a fluorescent light kit like this help?

http://www.tudoparafoto.com.br/media...ua-4-pe_as.jpg

Like I said, it´s a small personal project. There is no room for investing in something like an HMI, even if it´s just for renting.

[Don Bloom]

Are you planning on using the led as a fill to open up shadows going into the window OR using it to "take the place of the sun" as it moves thru the window?

[Rafael Lopes]

Open up the shadows without looking to artificial. Do you think the fluorescent light would be a more appropriate solution?

[Don Bloom]

Yep, I do. Unless you are planning on some 1X1 LED panels I don't think they would be powerful enough to cover the shadows without being in the framing. the small one are just to weak to be effective at any kind of distance.

[Rafael Lopes]

Thanks, Don.

[Arthur Gannis]

Led lights do come in variety of brightness or should I say lumen/lux figures. In general the narrower beam, the brighter the light will become. That is why any led light fixture that has a wide and/to narrow field of coverage may show a huge difference in brightness when going from wide to narrow. That difference may be as high as 4 F stops difference depending on the angle of the beam. As a very rough guide, one may consider that a household 100 watt ( it consumes 100 watts from the utility company) light bulb has a brightness rating of approximately 1800 lumens emanating from it. Led lights are generally measured with a LUX rating at the standard 1 meter ( 3ft) distance as a brightness reference. It is not uncommon to see a led light have a whopping 10,000 lux at 1 meter when it projects a very narrow beam like 6-10 degrees. That same light would most probably have a 1200 lux rating if the beam was widened out for a larger area. A led light to be effective at say a distance of 4 metres ( 12 ft.) for daylight fill, would need approximately 1400 lux at subject surface which at 4 meter distance would require the led light to be 16X as bright ( the inverse square law of light) so 16 X 1400lux = 22,400 lux. Almost impossible to find one even remotely close to that UNLESS the beam angle is narrowed down or in the area of 10-15 degrees.Now you would have a powerful fill light for the shadows at a comfortable working distance and that beam would cover an area of approx 4 feet high X 4 feet wide. That would be the same brightness and coverage of a 1400lux light BUT at a shorter distance of 1 meter. The narrow beam was NOT creating more lumens but channeled all the lumens in a tighter area for a brighter surface lux value. Sunlight brightness, even through a window and reflected off another surface is a tough to deal with, perhaps a silvered reflector is sometimes best suited ( and cheaper) than a light source. You can even shut down existing flos or incans bu using this method. Then again, it depends on the given situation and effect desired.