dione961 wrote:
So I have no shoot-able daylight now - weeks on end of rain, snow, howling wind plus 4 hours of sun above the horizon!!) so I plan to set up & shoot a whole range of small things in many different ways, indoors. But, we are house sitting a dark Alaskan cabin so I can't change the (dismal) interior lighting and cannot go buy 110v lights or bulky photographic equipment as we will only be in the cabin until April then it's back to sea to keep sailing around the Alaskan coast to BC.
I need a USB re-chargeable portable light so I can use it when we get back onto the boat & charge it off my PC (which hooks to the boat's 12v system). It needs to be off-tripod, preferably variable intensity, and, sorry to say it, reasonably priced!! Thanks for any thoughts!
So I have no shoot-able daylight now - weeks on en... (
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I'm running this laptop right now from a 125 VAC inverter that is powered by a
bank of five 12 VDC marine deep-cycle batteries. The battery bank is charged
during the day by solar panels. I also have a wind generator.
To get lights bright enough for photography that will last long enough to
get though an evening's shooting, you'll need pretty big batteries (e.g.,
four 'D' cells or eight 'AA' cells minimum). Don't even consider a
rechargable device that takes special batteries.
USB has limited current. It wouldn't charge big batteries in a reasonable
length of time. And all batteries require some sort of charge controller.
The better your battery charger, the more cycles you'll get out of
rechargable batteries before you have to throw them away. Some
battery chemistries require a more sophisticated charger than others.
LEDs are very efficient, but most very poor color rendering capability
(low CRI). This has nothing to do with color temperature, it's about
the ability to reproduce particular spectral hues.
I have an LED light made by Sunpak for photography, and it's not great.
Small, easy to use, bright, looks white--but doesn't reproduce colors well.
(But it's fine for shooting B&W.)
So I'd recommend tungsten-halogen flashlight bulbs instead of LEDs.
As with any point source, you're going to need to bounce it off something
or pass it though a really large diffuser. A white umbrella works either way.
Could you get by with flash instead?