Convert Bracketed Photos for HDR
HDR Photography: How to Dial in Auto Bracketing
Shoot Multiple Auto Brackets in HDR Photography

Choose between More and Fewer Brackets in HDR

Reading about why you can or should shoot more or fewer brackets in high dynamic range (HDR) photography is one thing. Seeing the difference among different numbers of brackets of the same scene — and comparing them in Raw versus JPEG format — is even more illuminating.

These figures present a close crop of the same scene, processed using different numbers of brackets in different formats. The final, processed shot (nine exposures from TIFFs) is shown here. For the upcoming examples, the camera was zoomed in on the sun and tree line to show both extremes of the spectrum of light and dark in this scene.

image0.jpg

This figure illustrates an HDR image tone mapped from JPEG brackets. Pay special attention to the sun, the rays of light, clouds, the tops of the trees, and the shadows in the trees.

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This table summarizes what can be gleaned from looking at the different swatches in the figure.

Comparing JPEG Brackets in HDR Photography
Brackets EV Difference Total EV Range Notes
2 4.0 4 Surprisingly good from a distance; posterized close in; noisy
3 2.0 4 Much better; smoother gradations of color; less noise
5 1.0 4 Very good; even smoother and less noise
5 2.0 8 Better dynamic range (look at the shadows); posterization (you have to be zoomed in quite a ways to see it) and noise problems
7 1.0 6 Very good dynamic range, less noise
9 1.0 8 Best image quality; greatest dynamic range with fewest problems

Overall, JPEGs perform well. If you look at the overall image versus this magnified area, they all look pretty good. If that’s your intent, you don’t need to overdo it. Shooting more brackets at a smaller EV distance lowers noise and gives you a smoother gradation between colors.

This figure illustrates the same scene created from brackets shot in Raw and converted to TIFF. Compare each set of images in terms of the number of brackets and their EV difference. Make sure to compare similar images between JPEG and TIFF.

image2.jpg

This table summarizes the differences among the number of brackets when created from Raw exposures converted to 16-bit TIFFs.

Comparing TIFF (from Raw) Brackets in HDR Photography
Brackets EV Difference Total EV Range Notes
2 4.0 4 Better range than comparable JPEG; smoother; some noise problems
3 2.0 4 A definite improvement over 2 exposures; a bit noisy
5 1.0 4 Very good; less noise
5 2.0 8 Large dynamic range; less noise
7 1.0 6 Smooth; good looking
9 1.0 8 Excellent dynamic range; very low noise

Even at the lowest level, 16-bit TIFFs (from Raw) perform better than JPEGs because there is more dynamic range inherent in a 16-bit TIFF than in an 8-bit JPEG. Is the difference earth-shattering? Not really, but if you’re going for the highest-quality image that can be printed out at a larger size to sell, TIFFs do make a definite difference.

The quality improvement in TIFFs mirrors that seen in JPEGs. The more brackets you shoot, the greater the dynamic range you capture. Shooting with a smaller EV difference (+/-1.0 EV) results in less noise, and a combination of more brackets with small EV differences results in smoother color. The difference between five exposures shot at +/-1.0 EV rather than +/-2.0 EV shows this trade-off very well.

The bottom line is to shoot as many brackets in Raw as practical with a small EV difference if you want the highest quality. Three brackets at +/-2.0 and five brackets at +/-1.0 EV are good for most situations. Use JPEGs if you want a good image but aren’t concerned about getting the most quality possible.

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