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Anthony DePasquale February 25th, 2012 11:55 AM

Video Light Help
 
I just bought a used NRG Vari-lite. A 65 watt hr belt pack and the NRG 680 Charger, for $150.
Was that a good price? I charged the pack and ran it full 50 watts and it lasted for 1 hour. Does that sound right. I am trying it at 1/2 power next. I shoot with a PD-150, will 25 watts of light be enough for sweet 16 parties and wedding receptions?

Also I have a bescor 12 volt over the shoulder battery from an older light, does anyone know if i can use the NRG charger with the Bescor Battery?


Thanks

Don Bloom February 25th, 2012 12:15 PM

Re: Video Light Help
 
25w should be more than enough for you. I still use both a150 and a 170 with a Litepanel Micro with both a diffusion filter a a 1/4 cto and 6 db of gain and it works fine. Keep in mind though that the effective throw of the light is about 6 to 8 feet. After that the effectiveness goes way down.

Arthur Gannis February 25th, 2012 06:50 PM

Re: Video Light Help
 
The halogen filament bulbs, although color temperature is quite constant when battery is fully charged, will eventually go to yellow and orange as the voltage drops. By having the 50 watt light reduced to 25 watts may
depending on the dimmer type, consume just the same as the 50 watt one if the dimmer is "burning off" the excess voltage as heat. So 25 watts to the bulb and 25 watts to the dimmer. You may have to do an actual test to determine if that is the case. What I would suggest is to change the 50 watt bulb for a 25 watt one if you need extended run time. Even with the 25 watt bulb, it will go to yellow and orange as all bulb filaments act that way, but at a later time nearing battery exhaustion. A 25 watt bulb really consumes 25 watts and is equivalent to approximately 450 lux at 3 ft. if you will be doing some comparison with leds in the future. Remember that to have the SAME amount of brightness at double the distance, you will need to multiply the brightness by a factor of 4 and not 2.
So if your 25 watt bulb is fine at 8 feet, you will need a 100 watt bulb to be the same brightness at 16 feet. If later on you go for leds, just remember that a led light rated say 1750 lux at 3 feet ( the usual rated distance)
is like the approximate brightness of a 100 watt bulb and may consume less than 25 watts of power. So really you can have that 100 watt bulb equivalent for a paltry 25 watt.

Arthur Gannis February 25th, 2012 07:24 PM

Re: Video Light Help
 
Using the NRG charger to charge up the Bescor may not be a good idea due to the possibility of the 2 types of batteries may have different chemistries ( MiMH vs Lead acid or perhaps Li-ion). Also the charge current may be too high if it is a rapid charger and made specifically for the NRG's. I am sure Bescor has a low priced (as compared to NRG) charger made specifically for their type of batteries, I would not chance it, as that is really a safety issue. Then it would be a good idea to have chargers going to their respective batteries, for days of really extended shooting.


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