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Shadow noise/latitude

The latest generation of sensor (as seen in the Sony A580, Nikon D7000 and Pentax K-5), has gained a great deal of dynamic range at low ISOs with a new design that offers much lower (sensor/electronics-derived) read noise. This means that much of the detail captured in shadow regions can be pulled back into images without bringing too much noise at the same time, giving tremendous latitude in post-processing.

Sadly the GF2's sensor isn't as impressive as these much newer ones, so as soon as you lift the shadow regions the noise becomes immediately apparent. This means that what you see in the JPEGs is essentially all you're likely to get. As you can see in 'Real-world shadow noise' section further down this page, some shadow noise can creep into low ISO images even without trying to pull the brightness up, so there's relatively little latitude for adjusting exposure when processing GF2 files.

In the example below we've illustrated this by pulling up the shadows using Adobe Camera Raw with all noise reduction turned off, to give the closest possible representation of the two sensors' inherent capabilities. As you can see, the shadow noise levels are substantially higher from the GF2. Normally, of course, you'd use noise reduction to address this, but this inevitably comes at the cost of a loss of detail.

Panasonic DMC GF2 - ACR+3.0EV Nikon D7000 - ACR+3.0EV
100% crop 100% crop
100% crop 100% crop

Metering / highlight recovery

The GF2 follows in a long line of Panasonic G-series models that meter very distinctly to retain highlight detail, only blowing out significant regions of the image in very high contrast situations. This conservative approach pays dividends, and you very, very rarely find yourself trying to recover blown detail from raw files. However the flipside is that it can sometimes leave the GF2's JPEGs looking a little dull and underexposed.

When you do go looking for more highlight detail in raw files, though, you start to appreciate the GF2's metering all the more, because there's really very little extra to be recovered. In the few overexposed raw files we obtained from the hundreds we shot, we could recover at best half a stop more highlight detail, and with essentially no colour information at all.

In the example below, exposing to retain detail in the statue has resulted in the stonework of the building blowing out to white. With just -0.5 EV compensation applied in Adobe Camera Raw we get colour shifts little meaningful extra detail and colour shifts in the brightest tones; pull the exposure down further and the recovered regions are rendered grey. In such situations we'd normally hope to see better.

Camera JPEG 100% crop
Raw conversion, -0.5 EV compensation 100% crop
Raw conversion, -1 EV compensation 100% crop

Overall Image Quality / Specifics

The Panasonic's JPEG images are quite good but rarely offer anything exceptional. Their color is generally pleasant enough without being stunning, while detail levels are reasonable but far from outstanding. Overall we regularly found ourselves looking at shots and wondering 'What I can get out of the raw file?' rather than really being happy with the out-of-camera result.

Auto white balance

The GF2's auto white balance can often get things subtly wrong, erring on the cool side and sometimes giving images an unpleasant cyan cast. Coupled with the camera's slightly muted color palette and tendency to err on the side of underexposure, this results in images which just don't look quite right, and certainly lack the immediate visual appeal of the warm, saturated JPEGs that Olympus Pens deliver out of the box. The solution to this is either to use a preset white balance instead of auto, or shoot in raw mode.

Camera JPEG - Auto White Balance Raw conversion - manual White Balance
Camera JPEG - Auto White Balance Raw conversion - manual White Balance

Shadow noise

Noise is also not one of the GF2's strengths, with chroma noise beginning to appear in the darker regions of the image at moderate ISO settings even in balanced light. The sensor wasn't exactly class-leading when it was introduced and now, some two-and-a-half years later, is really starting to show its age. Great leaps are currently being made in sensor design and the 12MP Panasonic chip simply can't keep up (this is, of course, compounded by being around 25% smaller than the sensors used in APS-C cameras). Ironically, Olympus seems to be able to get rather more out of this sensor than Panasonic can itself.

ISO 200, 1/2000th sec 100% crop

Detail and sharpening

Detail rendition also isn't one of the strong points of the GF2's JPEGs - due to a combination of somewhat crude wide radius sharpening and (at higher ISOs) enthusiastic luminance noise reduction, fine detail is often absent from the images (especially in low contrast monochromatic regions). This means subjects such as hair aren't always rendered convincingly, and even high contrast detail can end up as something of a jumbled mess.

Converting from raw immediately solves the issue, and with a careful choice of sharpening parameters an impressive amount of fine detail can be extracted (it's clear the GF2 follows the Panasonic tradition of using a relatively light anti-aliasing filter). So the detail is being captured, it's just that the JPEG engine isn't rendering it terribly well.

Camera JPEG Raw + ACR 6.3, smart sharpen in PS CS3 (Radius 0.3, Amount 260)
100% crop 100% crop
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