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Dynamic Range

Our Dynamic Range measurement system involves shooting a calibrated Stouffer Step Wedge (13 stops total range) which is backlit using a daylight balanced lamp (98 CRI). A single shot of this produces a gray scale wedge from (the cameras) black to clipped white (example below). Each step of the scale is equivalent to 1/3 EV (a third of a stop), we select one step as 'middle gray' and measure outwards to define the dynamic range. Hence there are 'two sides' to our results, the amount of shadow range (below middle gray) and the amount of highlight range (above middle gray).

To most people highlight range is the first thing they think about when talking about dynamic range, that is the amount of highlight detail the camera can capture before it clips to white. Shadow range is more complicated; in our test we stop measuring values below middle gray as soon as the luminance value drops below our defined 'black point' (about 2% luminance) or the signal-to-noise ratio drops below a predefined value (where shadow detail would be swamped by noise), whichever comes first.

Picture Style options

As we have previously seen on Canons, the various Picture Styles use either one of two tone curves, the first more contrasty curve for Standard, Portrait, Landscape and Monochrome Picture Styles and a slightly flatter curve for Neutral and Faithful Picture Styles. Neither curve delivers more dynamic range and they both clip highlights at the same point.

ISO Sensitivity and Dynamic Range

Although noise cuts the shadow range a little at IS0 1600 the EOS 1000D's JPEG dynamic range is pretty consistent across the range, and offers an essentially imperceptible improvement over the EOS 400D (mainly in the shadow region - probably due to increased noise reduction). The range - around 8.7 EV - is fairly typical for a camera at this level (and is consistent with Canon's other APS-C offerings).

Sensitivity Shadow range Highlight range Usable range
ISO 100 -5.2 EV 3.5 EV 8.7 EV
ISO 200 -5.2 EV 3.6 EV 8.8 EV
ISO 400 -5.2 EV 3.6 EV 8.8 EV
ISO 800 -5.0 EV 3.7 EV 8.7 EV
ISO 1600 -4.0 EV 3.9 EV 7.9 EV

Dynamic Range compared

The EOS 1000D is one of the better performers on the market, essentially matching the 450D and Sony A200. The Nikon gives a higher total usable range figure but lacks the highlight range of the other triumvirate. The Olympus E-420 is the only disappointment here, delivering two thirds of a stop less highlight range (in JPEG). There is no difference in highlight range between the 1000D and the 400D with which it shares a sensor, so the improvement in the shadow range is probably down to increased noise reduction.

Camera (base ISO)
Shadow range
Highlight range
Usable range
Canon EOS 1000D -5.2 EV 3.5 EV 8.7 EV
Canon EOS 450D -5.1 EV 3.6 EV 8.7 EV
Sony Alpha 200 -5.1 EV 3.6 EV 8.7 EV
Nikon D60 -5.7 EV 3.3 EV 9.0 EV
Canon EOS 400D -4.9 EV 3.5 EV 8.4 EV
Olympus E-420 -5.4 EV 2.8 EV 8.2 EV

The wedges below are created by our measurement system from the values read from the step wedge, the red lines indicate approximate shadow and highlight range (the dotted line indicating middle gray).






RAW headroom

Experience has told us that there is typically around 1 EV (one stop) of extra information available at the highlight end in RAW files and that a negative digital exposure compensation when converting such files can recover detail lost to over-exposure. As with previous reviews we settled on Adobe Camera RAW for conversion to retrieve the maximum dynamic range from our test shots.

As you can see the default Adobe Camera RAW conversion delivers less dynamic range than JPEG from the camera (a more contrasty tone curve and less noise reduction in shadows). The best we could achieve was just over 10 stops (10.2 EV) of total dynamic range, more importantly almost a stop of that is in highlights (although with no guarantee of color accuracy). This is pretty much the same as the EOS 400D and around 2/3 stop less than the EOS 40D.

  • ACR Default: Exp. 0.0 EV, Blacks 5, Contrast +25, Brightness 50, Curve Medium
  • ACR Auto: Exp. -0.95 EV, Blacks 0, Contrast 0, Brightness 0, Recovery 8, Curve Medium

The extent to which image data can be recovered from RAW files that would be over-exposed in the JPEG is not as impressive as it is with the 450D. Very little additional information appeared beyond 2EV of negative 'digital exposure compensation' applied and if you really push the files you'll start to lose color information and will eventually see posterization (which can be seen in these examples).

That said, using ACR to rescue shots such as these produces remarkably good results most of the time and certainly support the practice of shooting raw.

Adobe Camera RAW default conversion Adobe Camera RAW with -2.0 EV digital comp.
100% Crop 100% Crop
Adobe Camera RAW default conversion Adobe Camera RAW with -2.0 EV digital comp.
100% Crop 100% Crop
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