37th Poznań Linguistic Meeting

20-23 April 2006

PLM 2006
Photo Vault

PLM 2006 Photo Vault -- The Split Second Treat

A real-life comparison or multi-segment and spot metering modes plus a rare case of synchronicity

Presented below are two pictures taken similtaneously by two photographers facing each other. This can be treated as a rarity, hence the two pictures, apart from being displayed in galleries one and two in downsized form, are given links to their full-scale versions below.
Date: 2006/04/20
Time: 11h15m13s (i.e. during the questions time after Gereon Müller's plenary talk)

Roland Noske: Sony DSC-P150 (7.2 effective megapixel sensor, ultra compact)

Grzegorz Michalski: Nikon D50 (6 effecitve megapixel sensor, digital single-lens reflex) (full EXIF data for trainspotters preserved in the linked file)
Location: Room 402, the WSJO buliding, 5 Piekary St., Poznań (the room is somewhat L-shaped, which explains why you can see windows in both pictures)
When looking at the picture taken by Roland, you can notice the aperture on the Nikon, which is shooting at 1/50-F/5.6 with no flash. Through the opening, the flash from Roland's camera can be seen reflected from the photo sensor on the Nikon. Conversely, when looking at the other picture, though you cannot see the aperture on the Sony, you can see the enourmous flash firing at the Nikon whose metering system could not have foreseen the flash, hence the picture is, say, +2EV overexposed.

The reason why the picture taken by Roland is so underexposed might be the amount of light coming from behind Grzegorz, making the camera's metering system, presumably set to multi-segment mode, calculate the amoung of light from the whole frame, hence forcing a very tiny aperture to avoid overexposure. Just take a look at the window in the centre of that picture. Good exposure. Compare that to the picture taken by Grzegorz, where he switched the metering system to so-called spot metering. Had Roland not used the flash, his face and the camera would have had a good exposure. This is would not have been true for the windows behind Roland. And it is not. Overexposure without any doubts.

Enjoy the pictures (click on either of these to get the full-scale version):
Taken by Roland with the Sony Taken by Grzegorz with the Nikon
Taken by Roland Taken by Grzegorz

Send your inquiries to Grzegorz Michalski, grzegorz (at) ifa amu edu pl.
 This particular page maintained by G Michalski