Re: Voltage drop ...
Yep, while it is tempting to just use a dropping resistor, if the load current changes, or if the input voltage changes, the resulting voltage to your sensitive video chips will vary. If you go much above 5.5 volts, they can fry.
A fixed 5 volt output regulator is pretty simple to make. Take a LM7805, put a 0.33 uF cap between the input pin and ground, put a 0.1 uF cap between the output pin and ground, connect the ground pin to ground< and you are done.
Anywhere from 7 to 35 volts in, and you get a steady 5 volts out at one amp. If you have a big voltage drop across the chip, you will need to heat sink it with a piece of aluminum.