Panasonic Lumix DMC-GH1

Sharpness

The highest sharpness results were found when shooting at the widest angle with the aperture wide open, producing a LWPH measurement of 1912 horizontally and 2007 vertically.While the typical variation of falling sharpness midway out from the center and rising again near the edges holds true, overall sharpness remains fairly consistent across the lens, without the severe trouble spots we sometimes see in our analysis. More on how we test sharpness.

Image Sharpness and Chromatic Aberration

Focal Length:

14.0mm

78.0mm

140.0mm

Click blue squares to change sample crops below
f/4 f/9 f/22
f/5.8 f/11 f/22
f/5.8 f/11 f/22

Image Stabilization (4.60)

Our tests of the GH1 image stabilization system revealed some benefits, though not a radical improvement. On the plus side, having image stabilization on never had a negative impact on resolution (which frequently occurs), and when the camera is shaking a lot and the shutter speeds are relatively fast (above 1/60 second), the system is quite effective. At slower shutter speeds and high camera shake, though, there was essentially no effect. And shooting with lower shake levels (about what you’d find when holding the camera with both hands), there was a slight benefit gained at slower shutter speeds.

We test a camera’s image stabilization by mounting it in a custom-designed motion-control rig that produces predictable, computer-controlled movements. A slanted-edge test chart is shot multiple times at a range of shutter speeds, both with the rig set to high shake and low shake, and with image stabilization turned on and off. The resulting images are analyzed using Imatest software to determine how effectively the image stabilization system improves actual resolution results.

The GH1 uses optical image stabilization, offering three image stabilization modes. Mode 1 employs image stabilization at all times when the camera is in Record mode, and Mode 2 only uses the system when the shutter button is pressed. Mode 3 compensates only for up and down movements, to allow smooth horizontal panning. Of course, stabilization can also be turned off altogether, using a switch on the lens barrel.

The low shake setting reflects typical shooting situations, when you’re holding the camera with two hands. As shown in the graphs above, the system proved effective at limitng horizontal shake at the two shutter speeds that generally mark the lower limits you’d expect to shoot handheld without flash, though at other speeds and for vertical shake the system didn’t offer much improvement.

When we cranked up to shake to high (as if you were trying to shoot one-handed, or while moving), there are significant effects on horizontal shake at 1/250 and 1/125 second shutter speeds, but not much else to brag about.

Image Stabilization Comparison Table			Expand
	Low Shake IS Off	Low Shake IS On	High Shake IS Off	High Shake IS On
1/500
1/250
1/125
1/60
1/30
1/15
1/8

The areas where the system proved effective, and the fact that it didn’t cause problems elsewhere, earned the GH1 a respectable if unexciting score for image stabilization. (We don’t have image stabilization scores for the Nikon D90, hence the missing data in our comparison chart.)