Now the EOS 7D has been in the wild for a little while, I thought it a good time to put up a short post about a little weirdness I've found with it.

Before the skeptics start laughing and pointing, it's nothing that affects image quality, it's simply a functionality thing. And besides, how many of you use Highlight Tone Priority or Auto Lighting Optimizer? No, thought not. 

So, The EOS 7D features both HTP and ALO (I'm going to use the acronyms because it's too long to type out the whole thing!). HTP shifts the dynamic range from the mid-tones to the highlights giving smoother tonal transition in highlight areas. ALO aims to even out contrast to create a better looking result and is especially useful when shooting backlit portraits, or portraits with flash. 

Now, the little bit of weirdness is that on other EOS models, you can use HTP and ALO together if you want. Or you can have HTP set at the time of shooting and add or subtract ALO later when processing in Canon's Digital Photo Professional software. On the EOS 7D though, you can't. If HTP is set, you cannot also set ALO. And if ALO is set on, then enabling HTP will disable it. Equally, you can't shoot with HTP on and then add ALO later in DPP. 

While this is probably not a huge issue for many users, it may be causing some confusion among users who do make use of these features. Why it should be the case is anyone's guess, but at least you now know. Stay tuned. If I find out any more, most notably a reason why, I'll be sure to let you know!