Auto Electrical - LED Lights

[PJ autoelectrical]

Good morning knowledge base.
I have a project involving auto electrical (so 12V DC, or 13.8V on a good day) and LED lighting. I have a pair LED lights (total 60W) that I would like to be dimmable via a switch. The lights will therefore be fed by two circuits (one with a fixed resistor for the dimming) and each circuit will also require a diode to avoid back feed. The circuits will be activated by a changeover switch (SPDT) to allow selecting between circuits (dimmed or full).

So my questions:
1. What size resistor would I need to put in one of the feeds to dim the lights (say 50%)? I assume Id need to consider both ohms as well as capacity (in watts).
2. What size diode would I need in each circuit to stop the back feed?

Thanks in anticipation for your assistance.

 

[mainline]

Good morning knowledge base.
I have a project involving auto electrical (so 12V DC, or 13.8V on a good day) and LED lighting. I have a pair LED lights (total 60W) that I would like to be dimmable via a switch. The lights will therefore be fed by two circuits (one with a fixed resistor for the dimming) and each circuit will also require a diode to avoid back feed. The circuits will be activated by a changeover switch (SPDT) to allow selecting between circuits (dimmed or full).

So my questions:
1. What size resistor would I need to put in one of the feeds to dim the lights (say 50%)? I assume Id need to consider both ohms as well as capacity (in watts).
2. What size diode would I need in each circuit to stop the back feed?

Thanks in anticipation for your assistance.

Why would you need 2 circuits diode etc when you could just use a 3 pole switch ? or a dimmer switch ?

 

[PJ autoelectrical]

Why would you need 2 circuits diode etc when you could just use a 3 pole switch ? or a dimmer switch ?

No dimmer, because its on a motor bike so just want a single switch on the handle bar. Ill have a think about the 3 way switch.
Ta