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 Ex oriente lux
 
Sony NEX underexposure recovery
 
Here's a little bit of a torture test. Grab an (obviously) underexposed shot, in tunhsten lighting, taken at high ISO, taken with a kit lens at the minimum focusing distance - where you have both black and white objects in the frame. Here you go:

Above: Sony E 18-55mm lens, f/3.5, 1/13 second, ISO 1600, at about 0.3m. Subject is 1.5m from a 60-watt tungsten light source. Red reflection on right side is from Christmas lights. This is not looking good. At all.

So take the Sony ARW file, plug it into Lightroom, click white balance on the white wall, hit Auto Tone, and jimmy a little with the noise reduction (no lens profile applied, since this is a test that needs to be valid both for the lens tested and legacy lenses that won't have profiles). You get:

Above: Same file rendered in Lightroom (temp 2000, tint -3, exposure +2.85, brightness +12, contrast +46, sharpening at default, luminance noise reduction 50, detail 50, color 50, detail 50).

Much better, no? Actually, it's pretty miraculous when you consider where this picture started (Lightroom could not delete the holiday light reflections from the Konica II on the right). But since we are very discriminating and want to know what's really in this corrected image, we have prepared some 100% blowups to show you what detail that chrome lens cap and black leatherette might contain.

This is the center of the Konica lens cap. Color noise is very effectively suppressed, though the lettering is not the sharpest surface in real life. It is also possible that the Steadyshot did not quite do the job. No, I take that back!

This is the shutter speed dial, slightly behind the intended plane of focus. Notable is the nice fine edge of the decorative black ring on the bezel.

If you look really, really, really hard, you can see where the chrome had a tiny bit of "discoloration" in the corrected image (it's not on the actual subject). At three stops of underexposure, though, it's miraculous that we are not seeing something much worse.

This is the leatherette, a bit more behind the plane of focus. Depending on the calibration of your monitor, you may be able to see the coarse pebbles of the leatherette on the Konica Standard, as well as the decorative line that extends horizontally about 2/3 of the way down from the top of the frame. So I guess the answer is that you get some shadow detail. Actually, it's a suprising amount. Yes, there is some blue-channel noise, but it's negligible.

You can draw your own conclusions, but with a modern rendering engine like Lightroom, it is indeed possible to see in the dark with what some people might consider a "toy" camera and its "crappy kit" lens. It makes one want to revisit D700 files with Lightroom to see whether its noiselessness can be pushed to ISO 6400...

 

DAST