Quote: (Originally Posted by
jhaaja)

I think I need to attach my 21W HID with the video reflector to the other flash arm that I do not own yet

to get enough light to get the focus locked.
I just hold the light with my left hand, lock the focus on the camera and before shooting the picture, take the divelight out of the picture again.
That way you avoid the divelight making any unwanted hotspots. With a videolight there is less tendency for hotspots.
But a videolight needs to be really bright to assist the camera in finding focus. That's why I don't use that. I have both narrow focus and videolight head for my 50w HID (metalsub 200) but prefer the narrow focus. Now if I had a 200w HMI, that would be another matter...
Another reason that I take the divelight out of the picture before shooting, is so it's easier to find out if one of your strobe is positioned the wrong way. It's often only minor ajustment in the strobeangle that makes the difference in how much backscatter you will get in the picture.
Too many variables makes it more difficult to get it right the first time.