This shows the effect of a dirty lens both internally and on the front element.
(exposure is also about 1/2 stop more to show the effect of dirt.)
Multiple diffuse flares instead of a single strong central flare like the 50mm f/1.4.
The light reflected from the sensor to the lens and back to the sensor has a bluish tone.
Possibly because of the nature of the IR,AR coating on the sensor filter.