R1, is a hybrid. Like a compact, its screen remains live while you're shooting. 
But like an S.L.R., it has a huge sensor inside, 21.5 x 14.4 mm. 
(For those scoring at home, a typical compact-camera sensor measures 5.7 by 4.2 mm.) The R1 captures 10.3-megapixel photos,


Sony DSC-R1
 
10.0 million effective pixels
10.8 million sensor photo detectors
24 mm - 120 mm (5x) zoom lens
Announced 08-Sep-05


a large format CMOS sensor (APS-C size)

RAW -> Adobe DNG 


December 8, 2005
David Pogue



....

 a $1,000 digital camera, the R1, 
 
 digital S.L.R.'s, like the Canon Digital Rebel and the Nikon D50, take far superior pictures. The light sensor inside these bulkier models is gigantic - 10 times the size of a typical compact's sensors, for 10 times the light sensitivity. You get sharper detail, more accurate color and less grainy shots in low light.

Unfortunately, ... on a digital S.L.R., you must hoist the camera up to your eye and peep through the little optical viewfinder. ... you don't even use the screen except when playing back photos.

Why can't a camera with a big sensor also offer a live preview screen?

That mammoth sensor is to blame. To supply a live video preview to the screen, the sensor would have to be turned on full time, wolfing down battery power, heating the camera interior and demanding high-horsepower circuitry.

.Sony   ...redesigned the sensor from scratch, with power and heat considerations at the top of the priority list. This new component .. consumes only one-tenth the electricity that would be required by a standard sensor at that size.

The resulting camera, the R1, is a hybrid. ..

The photos are spectacular.

And except in low light, this camera is free of shutter lag

By eliminating the mirror and prism, Sony was able to slide the lens barrel inward to within two millimeters of the light sensor.

.. this positioning grants you ..something that's never before been possible on a large-sensor camera: a wide-angle (24-mm) equivalent.... the R1 also zooms in 5X (a 120-mm equivalent). ...these are true 35-mm camera equivalents that don't have to be multiplied by, say, 1.5.

True to its S.L.R. heritage, the R1 is big, black and very heavy (two and a quarter pounds);
....

a big battery (500 shots..) and memory cards of two different formats: Memory Stick and Compact Flash.

.....It's a heck of a good lens, but you can't remove it...

.. that rotating screen; it's not Sony's best work. In this era of 2.5- and 3-inch digital camera screens, it somehow feels dinky (2 inches diagonal). Its clarity and motion smoothness are disappointing, too.

.. the eyepiece viewfinder .. you'll see only a second electronic display...

You also sacrifice a movie-capture mode..
and ... the closest this camera can get to its subject is 13 inches. 

....snaps a measly maximum of three shots in a burst.

.........

E-mail: Pogue@nytimes.com