Hi everyone, this is my first post on the forum, and I am fairly new to electronics so am still learning. I am thinking ahead to my first project already however, and although I know many others have done it, after seeing the film I cannot resist. I want to make an LED strip lightsaber, with the 'scrolling' effect of the light being deployed. To do this, I was planning to have 6 strings of 15 LED's, making 90 in total, delayed upon startup to produce 'scrolling' the effect.
My problem is that when conducting research as to how to achieve this, there seems to be many mixed responses. Some people appear to just straight up wire the LED's in a parallel chain with no resistor whatsoever, and some just have one resistor at the very start of each chain. I understand why this is a bad idea, due to runaway causing an imbalance, and the other LED's to fail, however was wondering what the best way to do this would therefore be? As mentioned, I will be 'chaining' the LED's in a line, and they will be grouped in 15's (the number of LED's is adjustable at this time).
I was planning to power the project with a 12v battery pack. Any help would be appreciated, apologies if I am just being a noob :P
Thanks in advance