I have the above mentioned light from Sony. I have an unusual problem that I think I read someone on this board had, but haven't been able to find the thread for it. My problem is that sometimes, if I turn off the light and then try to turn it back on, it doesn't work...simply will not turn on. I have found, and so had the previous poster with the same problem, that I must place the battery (Sony NP-F970) on the charger, even for just a second or two, and then replace it back onto the light and it works. This happens with the battery at any charge level, from full to nearly dead....I have 3 said batteries and they all do the same thing. Anyone else have this problem, and have any idea why it does this? Is it a light problem or a battery problem?

Jason,
The problem/flaw is that the draw is too high for the infolithium batteries. The internal fuse is being tripped and simply placing it on the charger for a few seconds re-sets the fuse.
Anything over an 18w draw for the L series can cause issues...however what Sony has done is ramp up the wattage to 20w (or so) so you don't have an instant drain of 20w the light dims up so it will be really warm color temp for a second before it hits the full wattage.
Doesn't mean there isn't a problem with your unit but basically it sounds like the fuse is being tripped. Does the issue happen when you only have the setting to 10w?

It happens for both wattage levels...sorry for the long delay in response