LED Flicker, UK Light Conversion

[johndm]

Having tried several makes of LED in the rears, ended up with Synetic bulbs.

This is a UK light conversion, so outers were changed to turn signals only, inners tail/brake.
To keep the original look, ended up with red/red LED's inners, and red/amber switchbacks in outers.

No matter which switchbacks I tried, they all flickered as soon as the engine was started, some makes even went out completely, so I took power for the outers from the licence plate feeds.

These Synetic LED's are ok to the naked eye, but inners flicker on camera (as do the side markers), but the outers stay solid.

Is this to do with bulb checking or just the LED's have differing refresh rates?