Panasonic Lumix DMC-GF1

Noise Reduction (5.26)

Image noise starts at a high level (around 1%) even at ISO 100, and nearly 1.5% with noise reduction at its lowest setting. Once you get past ISO 800 the noise levels render the images pretty much unusable unless you crank the noise reduction settings up all the way. The good news here, as shown in our sample photos, is that the noise reduction processing doesn’t obliterate too much image detail.

Image noise in the blue channel is slightly elevated above the rest, bad news for clean reproduction of those lovely blue skies in your photos. More on how we test noise.

We expect to see Four Thirds and Micro Four Thirds format cameras to produce more image noise than larger-format cameras, due to the small pixel size on the sensor, and the GF1 follows the pattern, with an undesirable level of speckling and artifacts even with bright illumination. It did, however, surpass the results we found when testing the Olympus E-P1. We test for image noise by shooting the X-Rite ColorChecker chart under bright 3000 lux studio illumination at all standard ISO levels and noise reduction settings. In the case of the GF1, Panasonic doesn’t allow high-ISO noise reduction to be turned off completely, so we shot at each of the five available levels by adjusting the Film Mode settings.

ISO Options

The GF1 offers settings from ISO 100-3200. If you prefer finer control, you can set ISO increments to 1/3 stop in the recording menu.

There are two flavors of automatic ISO adjustment, the standard Auto ISO based on light level and an additional Intelligent ISO system that factors in subject movement to boost ISO and shutter speed when called for. In either case, the user can set an upper ISO limit to prevent excessive image noise.

The following same-size crops are taken from photos of our standard still life, taken in aperture-priority mode with automatic white balance.

Focus Performance

Autofocus performance has been a key strength of the Lumix G series from the start, and this continues with the GF1. The Live View autofocus on most digital SLRs is too slow to be practical when shooting moving subjects. Panasonic, though, has figured out how to make contrast detect autofocus nearly as fast as the standard SLR phase detect system, and certainly workable for all but the most sports-oriented photography. This is an area where the GF1 has a clear advantage over the Olympus E-P1, which suffers from pokey autofocus speeds.

The continuous autofocus in video mode pioneered on the GH1 is also implemented on the GF1, though without the single 10x lens super-quiet the company provides as the GH1 kit lens, you may pick up some focusing noise while shooting in continuos autofocus mode.

The autofocus system supports four modes: 23 Area, Single Area, Face Detection, and AF Tracking.

It is also possible to select between AF-S (autofocus single) and AF-C (continuous) modes. AF-S focuses when you press the shutter halfway and maintains that setting, even if you move the camera. AF-C keeps refocusing as necessary while you hold the shutter down, even if your subject moves, or you move the camera. Yet another set of autofocus options are prefocus settings, available through the custom settings menu. Here you can choose from Q-AF (Quick Autofocus), which tries to autofocus whenever the camera is held still, and C-AF (Continuous Autofocus), which attempts to maintain focus at all times, even if the camera is moving and your finger is nowhere near the shutter button, with compatible lenses. Confusing terminology rules here (having both Autofocus Continuous and Continuous Autofocus as distinct choices isn’t playing fair), but you do get a lot of flexibility to handle different shooting situations. Of course, using the prefocus modes is going to result in a significant battery life hit.

There’s a bright red autofocus assist lamp on the front left, right below the LUMIX logo, which does a nice job when the lights are low. However, the positioning isn’t perfect. It’s very easy to cover up the lamp with your right middle finger while shooting, especially if you have large hands.

Panasonic continues with its odd variant to face detection, which it calls face recognition. You can register up to six faces in the camera’s built-in memory, complete with name, birthday and a priority rating if you choose. Then, when the feature is turned on during shooting, those registered faces will be given preferential treatment when focusing and setting exposure. The name can even be displayed on screen, for no apparent reason. The face recognition concept does have some interesting benefits, though. When taking group photos (at a school concert, for example), it will help make sure your little darling is in focus rather than some random kid. And during playback, it’s possible to view only images which include recognized faces.

Long Exposure (6.97)

In our long exposure test, which analyzes color accuracy and image noise over a range of shutter speeds, the GF1 again shows improvement over the GH1, but still comes up short compared to other cameras. We shoot the X-Rite ColorChecker chart under dim 20-lux illumination at shutter speeds ranging from 1 second to 30 seconds, with long exposure noise reduction on and off, then use Imatest software to determine the camera’s performance. More on how we test long exposure.

Color error is high across the board, with the long exposure filter having little effect. Saturation wasn’t bad, hovering around 100% before dipping significantly at the two longest exposure settings, but the color values are off throughout.

Image noise is quite high too and, as we sometimes see, the long exposure noise reduction system makes matters slightly worse. Long exposure noise reduction works by taking a second exposure with the shutter closed, then digitally removing the noise that appears in that second exposure from the image. Problem is, image noise is inherently random, so this approach is hit-and-miss at best.

The GF1 produced better results than the GH1, but comes up short compared to the Olympus E-P1, which also relies on a small Micro Four Thirds sensor, and substantially behind the Canon and Nikon with their APS-C format sensors.

The GF1 produced better results than the GH1, but comes up short compared to the Olympus E-P1, which also relies on a small Micro Four Thirds sensor, and substantially behind the Canon and Nikon with their APS-C format sensors.

Video: Low Light Sensitivity (0.66)

Low light sensitivity is not one of the Panasonic GF1’s strengths. The camera needed 25 lux of light to reach 50 IRE on our waveform monitor when we shot using its 30p frame rate (MJPEG compression), and it required 29 lux of light to reach the same levels when shooting at 60p (AVCHD Lite compression). These numbers aren’t that much worse than what we’ve seen from other video-DSLRs, but they are worse nonetheless.

A lot of factors go into determining low light sensitivity—ISO settings, lens specs, sensor size, and pixel count just to name a few. The GF1 has a fairly fast, f/1.7 lens, which is why we’re surprised to see it have such a poor low light sensitivity in video mode. In video mode the camera sets ISO and shutter speed automatically, so you cannot use a slow shutter to boost performance in low light.