[argyllcms] Re: Spotread -f and flash Guide Number calculation problem,

  • From: Matthieu DUBAIL <matthieu.dubail@xxxxxxxxx>
  • To: argyllcms@xxxxxxxxxxxxx
  • Date: Wed, 9 Feb 2011 19:05:58 +0100

To be more precise on the problem:
Relative measurement and calculation seams right (GN number and flash power
setting relationship ). See attached graphic.
But absolute GN number is wrong. Measurement was done using the flash's zoom
50mm setting. According to the Pentax manual, the GN number at 1/1 power
should be 45 in meter.

Matthieu DUBAIL

Attachment: Pentax AF540__Nombre_Guide.PNG
Description: PNG image

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