BlueMorel wrote:
Even I got the point - any shot with longer exposure might register times a neon has flicked off or on, not being a steady point of light. Or air, or any of the other points others have mentioned.
I think you may have this backwards. A short shutter speed may record during the "off" part of the cycle. A longer shutter speed will help. This is why before anti-flicker technology, the rule of thumb for shooting in light that is not continuous (quartz, halogen, fluorescent, neon, LED, etc) was to keep the exposure to less than 2X the cycle frequency to avoid flicker effects. In the US that would mean 1/125 second or slower.