How Hard Can It Be To Focus An Autofocus Camera?

The new Canon 5D Mark III is touted as having a much improved auto focus system compared to the 5D Mark II.  My test shots confirmed that it was fast and accurate.  Yesterday, I took it to my sister-in-law's 60th anniversary celebration to make the first of its photos that I intended to keep.  When I downloaded the results I found that I had the largest percentage of out of focus shots in recent memory.  How hard can it be to focus an auto focus camera?

The shots were made in a room that had a wall of windows on one side.  When I pointed the camera in that direction, I had to change settings to keep from having silhouettes.  Other than the windows, the room was fairly dark, so I kept 35mm lens set at f1.4.  A 35mm lens is usually pretty forgiving about focus but not at f1.4.

I've have plenty of plenty of practice focusing cameras.  You place the focusing spot on the sensor over the area you want to focus and press the button.  The camera makes a beep when focus is achieved and then you snap the photo.  In the case of the 5D Mark III, the camera also makes a red flash in the viewfinder at the time of focus.  It should be idiot proof.

Idiot proof solutions only work until you find a better idiot.   I guess that I qualify because I had trouble seeing the focusing spot in the first place.  I guessed and focus was confirmed with a brief flash and a beep.  When I downloaded the photos I found that the point of precise focus was not exactly where I intended it to be.

Today, I tried to analyze why I had difficulty.  

First, its very hard to see where the camera is set to focus.  The viewfinder is optically clear so the center is not visually different.  Second, the center is marked with a series of narrow black dashes.  The dashes show up fine against a white background but are hidden in many other situations.  The focus points are black squares.  The lines in the squares are a bit thicker than the lines around the circle, but they are difficult to see as well.

Second, focus confirmation only lasts a split second.  The black square changes to red when focus is achieved.  The red flash is an interesting touch, but it adds additional confusion when you don't know exactly where the black square was in the first place.  If you can't see where the black square is when the background is black it doesn't help to make the whole screen red when you are looking for a red square.

Third, the focus square changes back to black immediately after focus is achieved.  As a result, it is as hard to see as it was in the first place.

I work with software development for a living so I completely understand how easy it is to find design problems during testing.  If you don't spend enough time testing or don't listen to the testers, you end up with a product that fails in production.  If I find this problem the first time out, you would think that one of the Canon testers would have noticed it as well.  I don't intend for this to be a rant.  If Canon can't improve this problem with a firmware change, I'm sure that I can learn to live with it.  I am disappointed.  How hard can it be to test a camera to verify that an individual who has focused cameras for forty years can also focus this new improved model?