PetaPixel

Freeze Your Camera for Less Noise

Last Friday an anonymous poster on the photography board of 4chan sparked a discussion that rippled into the blogosphere after freezing their camera to see whether ISO performance improves at lower temperatures.

They stuck their Sony A350 into the freezer for 15 minutes, and posted the following before and after comparison of noise at ISO 3200:

Regardless of whether or not these results were fabricated, it has long been (though perhaps not widely) known among photographers that digital cameras have better ISO performance (i.e. less noise) at lower temperatures, which is why sensors are often cooled for astro-photography. Other photographers also report improved ISO performance when shooting in very cold environments.

Zodiac Light did an interesting experiment in which a Canon 350D was cooled, and the amount of noise measured. They found that cooling the sensor resulted in a 40% drop in the amount of noise.

Obviously you shouldn’t freeze your nice camera to test this out yourself, but it’s an interesting fact to know, and could be useful if you’re interested in long exposure photography.

(via The Phoblographer)


Thanks to Nathan Yan for briefing us on thermal noise.


Image credit: Don’t drop your camera! by Island-Life and used with permission.


 
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  • mijonju

    Gezzz that is nasty, hahah that doesnt even look frozan looks like fell into some.. ok nvm

  • mijonju

    Gezzz that is nasty, hahah that doesnt even look frozan looks like fell into some.. ok nvm

  • http://www.petapixel.com Michael Zhang

    Haha. That's not the camera that the post discusses, but was a “frozen camera” we found on Flickr.

  • http://shuttersounds.thedailynathan.com nathanyan

    I'm fairly skeptical of the 4chan discussion. The only type of noise that is related to the sensor temperature would be thermal or dark noise, which is the kind that looks like this:

    http://photo.net/learn/dark_noise/dark-64m-72F.jpg

    It's simply extra electrons that are recorded, but generally it's a very consistent addition to the source light information, not random fluctuation like you see in the 4chan example. That kind of noise is usually due to shot noise (photon noise) which is just random variation in the light level itself, and readout noise which is associated with the readout and amplification circuitry of the sensor.

    The kind of noise in the zodiaclight example is the same kind of additive noise – they measure the value of the red pixel on a dark frame, in which a noiseless image would be zero and would increase the more thermal noise. For shot noise and readout noise, however, which is just random fluctuation but doesn't actually change the average, the average pixel value on a dark frame would still be zero in theory (though it'll be a little higher in reality since the camera doesn't record negative brightness values, so the min is clipped to zero).

    The only explanation I can imagine would be readout noise being affected by temperature, but I don't think Sony's electronics would be that bad, and the effect should still be more akin to the additive noise rather than random fluctuation.

    I suppose this wouldn't be too hard to test – most of the Canon and Nikon cameras at least are rated to go down to 32F/0C. I might give it a try though I lack a thermometer to accurately assess the temperature.

  • mijonju

    haha, i see but still its pretty…. er.. hahaha..

  • http://www.facebook.com/people/Christian-D-Ritchie/722068218 Christian D. Ritchie

    Everyone wanting to try this ought to consider that if you bring your cooled camera into a relatively warmer environment(like out of the freezer into the kitchen), even for a few seconds, you are at risk of condensing water onto the lens elements, sensor, and electronics inside the camera…

  • http://shuttersounds.thedailynathan.com nathanyan

    The easy solution to this is to wrap your camera in a plastic bag before putting it into the fridge.

  • http://www.facebook.com/kkarneboge Kevin Karneboge

    And how would you take pictures with your camera in a bag?
    If you take it out the water in the air would condense.

  • ninpou_kobanashi

    goto Death Valley [CA] to shoot night stuff, but I stopped doing long exposures in the summer due to the sensor noise [as well as the crappy atmospherics] due to the heat. In winter, it’s much easier to get cleaner images, but you just gotta swap batteries more often.

    I was thinking of doing a write up of a black frame freezer / refrigerator / ambient / oven test to show the differences, but I don’t have infinite time on my hands.

  • Rudolf A. Hillebrecht

    Astronomers (amateurs as well) knew this for long. Their CCD-cameras are cooled down as far as possible to supress noise. There even is a housing for DSLR to achieve the same effect. So, this experience isn’t really new, but still surprising many.
    Rudolf A. Hillebrecht