3 point lighting kit questions

Norman99

Norman99

Well-known member
OK, I have an idea for a quick set-up/take-down run & gun interview lighting kit, but I have a few questions that perhaps some with more experience can help me with. First, the kit will be designed around 3 LED units that have only 2 leds in each light. I will go on to explain why 2 leds.The hair light with a 25 degree beam angle, and 2 lights with 45 degree beam angle. Also will include 2 small umbrellas ( silvered or white) that are 24 inches in diameter, 3 small tripods that go up to 5 feet and collapse down to 18".
The hair light will have a 3400 lux@ 3ft., the other 2 will be 2400 lux at 3 ft. Dimmer without flicker at any shutter speeds that dims from 0 to 100% and each light will have a 3 position color temperature switch of 3K-4K and 5K. CRI at 3K of 90, 4K of 85 and 5K not yet available but say around 80 to 85. Each light will have a Sony L series (NP-F) battery plate and a DC power in connector from any voltage between 7.2 to 20 DC.Each led light measures only 3 inches wide and will draw only 15 watts at full brightness. The entire kit will be contained in a small 20" wide X 14 inch deep and 5 inches high durable aluminum case and all will weigh in below 20 lbs.
Umbrella size question: Is 24" not big enough ? If not, what size is ideal?
Umbrella material : Which is best, silvered or white fabric, and why?
Tripod height: Is 5ft. high enough for most interviews ?
Color temp: Is 3K too warm ? Is 5K not cool enough ?
Battery plate: Is the Sony the most popular ? BPU series plate will be offered as an option.
Carry Case color: Black or chrome ?

The goal is to design the most compact battery powered 3 point light kit while at the same time having plenty of powering options and be rugged for the traveling pro.
All units are compact enough for on-camera use.
Photographers are increasingly using video constant light for quality photos.

Your input is appreciated. Thanks.
 
Why not a V-Mount battery system? I guess its a size thing, but any idea on how long they would last with a reasonably sized sony battery?
 
One led for 3000K the other for 5000K.
This way it will produce a single shadow on either 3K or 5K. Only in the 4K position will it make a tight double shadow as both leds are on. Being the leds are very close to each other, the double shadow will be minimal and only at 4K. Using 2 leds also allows the enclosure to be as compact as possible. 2 power class lighting leds will also allow the use of TIR (total internal reflection) optics that come in a huge variety of beam angles from a 6 degree super spot to 70 degree super wide. Something which is not possible using tightly spaced multi led design ( 126, 256, 312, 512 etc.)

The V mount battery system, or any battery system is fine, as long as the voltage is within the DC input range between 7.2 to 20. The V mount is 14.4V, which is perfect.
There are adapters that output the V mount to the light's DC in male barrel connector (2.1 X 5.5, center +). The units also have reverse polarity protection in case one wires up the power the other way around. It simply won't work. In this case just reverse the wires. The power draw from each light is around 18 watts. That means that a battery like a V mount 100 watt hour will run a light for slightly over 5 hours at full brightness ( 100 divided by 18). A Sony 4000ma rated NP-F 750 ( which is really a 30 watt hour.
7.2v X 4000ma) will run each light for around 70 minutes. The ideal compact longest running battery is the NP-F970 one which will take it to 150 minutes (2 1/2 hrs). If the unirs are dimmed down, they draw less power, as they only draw what is needed.
 
The lights would work fine without umbrellas but would be too hard on the eyes and would not have that soft light quality. The kit will be designed for maximum flexibility and can be set-up in no time. No need to look for power outlets, extension cords etc.
There are times when one wants a sharp single shadow look ( old B & W films) with specular highlights and high contrast. No soft umbrellas needed here. No umbrellas needed when a camera top light is required. Try doing that with a 1 X 1 large panel.
Speaking of camera top light, ENG coverage is a snap. They readily can be powered by the pro tap or d tap cable drawing power directly from the cam's battery. Indoor/outdoor color conversion is by the flick of a switch.
 
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