# The ISO of the XDcam PDW-530p...using a light meter

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### #1 Chris Albert

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Posted 16 July 2006 - 11:04 PM

I'm at the Maine Workshops in the US doing adv
Lighting and adv cinematography. Anyone know the ISO of
the PDW-530p?

I would be interested to know now as we
are being taught to shoot video film style using a
light meter.

Cheers, Chris
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### #2 Laurent Andrieux

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Posted 17 July 2006 - 07:00 AM

It's given a F 11 @ 200 fc, so it's suppozingly a 800 ISO rating.

I suggest you make tests on this basis
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### #3 Chris Albert

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Posted 17 July 2006 - 07:55 AM

Thanks for the quick reply...the Sony site gives it F11 @ 2000 Lux (not 200) is that what you meant? Sorry to be ignorant, but does this still make it ISO 800? (I'm not sure how to do the math you see.)

I am curious now while on the course what it is..definately will test it when returning home (Israel), although I think I will be a bit busy!
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### #4 Laurent Andrieux

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Posted 17 July 2006 - 09:22 AM

2000 lux is approx. 200 fc (1 fc = 10.70 lux). Most of the people here use foot candles, this is why I gave this value.

The math is N²/t = E.Siso/250

Where N is the iris value, t the exposure time (typically 1/50 s) E the requiired illumination in lux

There is an empiric rule "1, 2, 4" : 100 iso 2000 lux N (or F) = 4 that you can also put as : 1000 lux, 200 iso, N/F = 4

Regards,
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### #5 Simon Wyndham

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Posted 17 July 2006 - 03:56 PM

Not sure how accurate this sort of thing is really.

But this thread is kind of flying in the face of the other thread in the SDX900 forum asking the same question about that camera. The SDX is more sensitive than the PDW5xx series.
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### #6 Brian Drysdale

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Posted 17 July 2006 - 06:07 PM

The manual gives it as F 11 standard ( 89.9% reflectance chart, 2000 lux).

I assume this is the standard measurement method used by all the camera manufacturers.

I expect it doesn't include the transmission losses you'd find on a zoom lens.

Edited by Brian Drysdale, 17 July 2006 - 06:09 PM.

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### #7 Laurent Andrieux

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Posted 17 July 2006 - 07:09 PM

Interesting point. Video and cinema lenses in general are supposed to be marked with T stops, that take account of this loss.
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### #8 Brian Drysdale

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Posted 18 July 2006 - 03:59 AM

Interesting point. Video and cinema lenses in general are supposed to be marked with T stops, that take account of this loss.

Certainly film lenses are marked in T stops, however, I've never seen a standard video lens having T stops and only f stops are usually given in their spec sheets.

Although, the Canon HD Electronic Cinematography lens do have T stops mentioned in their specs. However, the ENG/EFP versions have their aperture given in f stops.

For example the Canon HD 11 x 4.7 EC is T2.1 and the ENG/EFP version is f 1.9.
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