Hi guys and thank you so much for your help in advance.
Using the above diagram as a rough approach, i have decided on an attack plan..
First I will mod an old PC Atx PSU as these have stable, regulated rails at 12v, 5v and 3.3v with lots of amps available
As above in attachment, I will be running strings of 3watt leds (3.2 - 3.6v, 700mA) and I'm thinking I can , in theory, put a potentiometer between r1(obviously the correct levelling resistor) and d1 to control dimming? Would this be possible? Would each series string or "set" dim evenly or would only the last led on the string loose current/voltage? Or have I got the whole circuit type wrong?
Sorry, but I'm somewhat new to all this.