During my week long HDR project I discovered a few tips that you should know about the Canon 40D when shooting a series of images intended for HDR (high dynamic range) processing. The whole idea behind these tips is to obtain three (or more) exposures of exactly the same scene so that your HDR software can easily and accurately merge these into one high dynamic range image.
- The first trick is to set your 40D to Aperture Priority Mode (Av) to ensure that your depth of field doesn’t change with each new exposure. This step is critical to obtaining a tack sharp HDR image.
- The second is to enable Highlight Tone Priority by selecting C.Fn II:Image -3 and setting it to 1 (Enable). This mode extends the dynamic range so that gradations between highlight tones becomes smoother. It also helps recover some amount of blown-out highlights but in my experience, the effect is subtle.
- The third is to bracket your exposures by the amount required to obtain the greatest dynamic range. Since the Canon 40D will only automatically bracket three shots, I usually set the Auto Exposure Bracketing (AEB) function to 1-1/2 EV or 2 EV for best results.
- The fourth and probably most important trick (at least in my limited HDR experience) is to use a good quality tripod legs and ball-head to minimize camera vibrations. I use a Gitzo Traveller tripod with a Really Right Stuff ball-head whenever I’m shooting landscape work. Together, they provide a lightweight and stabile platform to shoot from.
Another great technique for shooting HDR using the Canon 40D is called High Speed HDR where you use the camera’s highest burst rate (6.5 fps for the 40D) to capture the three bracketed exposures, even when hand-held. I haven’t tried this technique yet, but it sounds promising.
A final note. I’ve been a Canon shooter for over 30 years and never really considered switching to Nikon until lately. Why is it that most “prosumer” Canon bodies limit exposure compensation to -2 to +2 EV in 1/3 EV or 1/2 EV steps, while Nikon bodies allow exposure compensation to -5 to +5 EV in 1/2 or 1/3 EV steps? I find it surprising that Canon fails to see how this limitation makes the Nikon DSLRs much more desirable for HDR work.
A final, final note. I found another great article about shooting HDR using Canon DSLRs on the Canon Digital Learning Center’s web site. This was written by Uwe Steinmueller, the same author that wrote the High Speed HDR article referenced earlier in this post.