Do you think that would work for a led conversion?

[jfiresto]

The LM2596 is a classic. If you do not mind the design, another possibility might be a linear, constant current LED driver with a PWM input, of the sort some automotive makers favor, for example a TLE4242G. I have a few small boards using them that I salvaged from junked tail lights. I have not checked, but they may take a PWM signal from upstream, to make an LED serve as either a position or rear fog light.

[smollerthings]

Yes, the design I am gonna try is the LM2596 as driver (Switching frequency, 150 KHZ) with a PWM after (PWM frequency: 20khz). We will see how this goes. 12V 2.5 A wall transformer and 12V LED chip/spot.

If this works, even for video, I think it is quite a cost efficient solution for 3W-10W LED setups.