Does this allow me to power an Aputure 100d with V-Mount Batteries?

Off The Mark wrote:

What would be your suggested lux rating at 1m for a key light then?

You asked this question earlier, and hopefully others will respond to this question, too.

It is not easy to answer "how many LUX does a key light need," because you have to determine whether:

1) Will you be using hard (direct) light, or soft (diffused) light?

Hard light requires LESS LUX than soft light because things like diffusion, or bouncing off of walls / ceilings / bounce boards, reduces the efficiency of light. Plus the type of modifier used to diffuse the light is important, since some modifiers (like softboxes or beauty dishes) are more efficient than other modifiers (like umbrellas or scrims or bounce boards, which tend to scatter light).

Also, if you use a grid on a softbox, you are reducing light as well.

2) Some lights have "built in" reflectors that limit beam spread and thus increase the LUX ratings. The light you linked to had a limited beam angle due to it's "built in" reflector. This can be helpful when you want direct light (or even when bouncing the light), but it is not so good when used with modifiers such as softboxes because the spread might not be wide enough to get a very diffused (soft) light. You could use a scrim, but scrims are not as efficient as softboxes and since the beam angle is so narrow of that light, you have to move the ight further back away from the scrim to cover a large enough area of the scrim to make the light soft. But moving the light further back means less light (because of inverse square law).

There are other issues as well you have to consider. A smaller light running at 100% might have significantly more fan noise than a larger light running at 50% (the fans on the VL150 I mentioned don't even turn on if the power is kept at under 40%, for example).

Plus, just as with still photography, you might want to feather the light (angle the softbox about 45-degrees away from the subject so the lighting is less direct). I have a big 60-inch round softbox which should be very soft lighting even when pointing directly at the subject. But I still feather it anyway because I want some light from my softbox to bounce off of a bounce board on the opposite side of the subject to provide fill light, and because I often use a green screen and I want to prevent shadows cast by the subject from falling on the green screen.

So in short, for me, the MORE LUX that covers a wider area, the better.

Sorry there isn't an easy answer.

Hi, thank you very much for your extremely informative reply. It helped me a lot!