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b4cktr4ck
09-06-2013, 10:38pm
Hi,

I was reading this post http://www.dpreview.com/forums/thread/3499860 in regard of light frequency and shutter speed.
Do you know what is the frequency of florescent light in Australia?

Darey
09-06-2013, 10:44pm
The frequency is the same as the power supply which is 50 Htz.
Which means 50 cycles per second.

jjphoto
09-06-2013, 10:59pm
The frequency is the same as the power supply which is 50 Htz.
Which means 50 cycles per second.

Not always as it depends on the ballast used, but normal inductive ballasts work at mains, ie 50Hz.

Electronic ballasts are fairly common and can run at very high frequency so there is no flicker at all.

johndom
26-07-2013, 8:55pm
Professional fluorescent lights do have electronic ballasts and put out around 25Khz- 25000 cycles per second so they wouldnt worry you even if you were shooting 1000fps film.
Your run of the mill office flouro generally does 50hz, if you are shooting at 1/50th or 100/th you should not have any exposure problems. 1/200th becomes potentially problematic.
Looking (briefly) at that thread, if you are worried about wb variations- use a flash to cover the foreground, shoot raw (why would you do anything else?) and you can twist out the tubes directly affecting your subject if you have to.