Skip,
I found an interesting article here:
http://www.rit.edu/~andpph/text-streak.html
Apparently in Super FP mode, the F280 pulses about 10000 Hertz. This implies
that the F280 would flash 5 times during a 0.5 millisecond exposure. That does
not sound equivalent to continuous lighting. For example, with moving
hummingbird wings, this could yield some interesting artifacts.
It's also too bad that the engineers didn't make the F280 capable of delivering
a very bright duration of a few milliseconds that supports a shutter speed of
1/2000s with a reasonably strong guide number.
Matt
At 15:36 27-04-03 -0500, Skip Williams wrote:
>Yes, it pulses during the exposure in Super FP mode. The flash duration is
>20-40 milliseconds. That way as the slit window passes over the film, the
>flash is putting out essentially continuous light. Also, a Super FP flash
>pulse is triggered when the first curtain is released, whereas normal flash is
>triggered when the first curtain completes it's opening. If you shift to
>normal OTF flash, the duration is cut to 25 microseconds to 1 millisecond.
>
>I don't know how many other cameras offer this, but the Leica M7 also has the
>"HSS" (High Speed Synch) feature when you use a Metz 54MZ3 flash up to 1/1000.
>
>I found my info in an OM-4Ti brochure. Peter's got it here:
>http://www.deakin.edu.au/~peterg/brochure_pdfs/om4tichamp_0886D.pdf. A
>brochure from 1992 says the same thing.
>
>Skip
>
>>Subject: [OM] F280 FP
>> From: Matt BenDaniel <matt@xxxxxxxxxxxx>
>> Date: Sun, 27 Apr 2003 02:58:54 -0400
>> To: olympus@xxxxxxxxxxxxxxx
>>
>>How does the F280 work in FP mode?
>>Does it flash at a rate of 40000 times per second during the flash duration
>>(e.g. 1/50 second)?
>>
>>Is there a book on OM equipment that contains detailed technical information
>>like this?
>>--
>>Matt BenDaniel
>>matt@xxxxxxxxxxxx
>>http://starmatt.com
--
Matt BenDaniel
matt@xxxxxxxxxxxx
http://starmatt.com
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