Posts: 8,854
Threads: 318
Joined: Feb 2012
Location: Arizona/Minnesota
Yup, it's because of the strobe effect. That's why you should never have just a fluorescent light above your table saw. Include an incandescent bulb also to help eliminate the strobe effect which can make the saw blade appear to be not turning. I know of someone who got their finger cut off as a result of the strobe effect.
Ed
Posts: 537
Threads: 15
Joined: Jun 2012
Location: Cambridge, England
The 50Hz "ripple" can be seen on an incandescent bulb too, if you hook a high speed Cadmium Sulphate photo resistor up via a battery and measure the output on an oscilloscope but no where near as much as with a fluorescent tube or these days a compact fluorescent bulb (tricky little blighters look just like a proper bulb but strobe like a fluoro tube). Halogen spot lights whether high or low voltage, strobe less than even an old school bulb due to the thicker filament so use these on your work lights to get away from strobing issues.
Regards
Rick
Whatever it is, do it today, Tomorrow may not be an option and regret outlasts fatigue.
Posts: 535
Threads: 39
Joined: Jan 2013
Location: Kelowna, BC, Canada
I built an optical tachometer years ago to measure engine speed on RC airplanes. I used standard light bulbs to calibrate it. Definite strobe effect.
Mike
If you can't get one, make one.
Hawkeye, proud to be a member of MetalworkingFun Forum since Jan 2013.