Hair Light

Ok, I need some serious help with hair lights. 

Let's say I have my main at f8, do I set my hair light for f8 where it hits their hair? 

Where do you guys position your hair lights?  I put mine over her head and I got some lovely shadows, my guess is further back then?
I also tried using it like a background light and pointing it toward my model's head instead... that didn't seem to do anything, maybe I had it set at too low of a power...  I don't know.

That seems opposite, wouldn't I want less light for a blonde then?

Sounds like me when setting my lights, main needs to be the lower number, fill is the higher, wait, reverse that... I think.

Like the sun, above and slight , ever so slight back, watch for light bleed on forehead etc.

There are a number of views about the size of the hair light.  I have seen some photographers use a very large softbox so that the model can move all over the set without affecting it.

The light should be placed slightly behind and depending on the effect that you are looking for, close to the subject.  If the light is placed close (low) the effect will only be seen on the hair and will not spill to the shoulders (due to falloff).  If the light is placed farther from the subject, it will act more like a separation light and spill onto the shoulders or arms depending on the pose.

Yes, less light for a blonde . . .

As far as metering goes, you have to remember that the light coming to the camera will be similar to that from a kick light.  If you set to the same reading as your main, it will be brighter.

I hope this helps,

Ed

General rules of thumb (according to Travis, for what it's worth):

For dark hair, 1:1 (metered) between the main and the hair.
For light/white hair, 1/2-1 full stop less than main.
No hair... no hair (light)

Remember that the angle of incidence is equal to the angle of reflection.  This means that there is more light reflecting from the subject to the lens from a hair light than from a main light because the hair light is pointed in the same general direction as the camera.  This light will appear much brighter (same as a kicker) and will require closer control to maintain details in the specular highlights it will create.  Also, watch very closely for lens flare, it may be mild and just enough to drop the overall contrast of the image, but still problematic.  Again, the light is pointing at the lens, more or less, so be aware of it all the time.

Travis