Here's a few shots form my Ski Trip to Killington, Vermont.


These are tracking head on at a pretty decent speed, which is usually difficult for a camera. These are obviously handheld while I'm on my own skis with my back facing down the mountain, with my skis in a reverse snow plow.


Last year, there were some reports of the MK IV having difficulty tracking head-on when a red color jersey was worn in bright sunlight.


http://www.robgalbraith.com/bins/multi_page.asp?cid=7-10048-10484-10500


Excerpt from the article:


"Two of those tops are shown in the downloadable runner sequences: blue (the PV singlet), and as you'll see, the results are good to great, plus red, where there is more than one instance of the dreaded EOS-1D Mark IV frontfocus shift. We shot other tops too, but it was really only the red that set off any alarm bells. Still, how the camera performed with the runner wearing the red top was not anywhere near as poor as in other more real world situations, such as sunny soccer."





The above article was written over a year ago, so it looks like Canon listened to their customers and they have appeared to improve/fix any problems that this body may have had initially.


Even, Bryan as mentioned in his review, had some sporadic results and inconsistent AF tracking early on, however he mentioned that Canon had addressed some initial concerns and that the MK IV was improved over time.


Here are a couple of other articles and testing regrading the Canon Mk IV.
<div>http://www.prophotohome.com/news/2010/03/01/rob-galbraith-says-canon-1d-mkiv-auto-focus-still-unreliable-is-it-true-2/</div>


http://www.prophotohome.com/news/2010/03/01/autofocus-torture-test-updated-canon-1d-mkiv-nikon-d3s-added/





So.., I would just like to share some of my personal experiences so far.


The photos below look much better on Flickr, where the entire series may be viewed in sequential order. If you hit next button quickly once you're on the link, it looks like a slow motion movie.


http://www.flickr.com/photos/53022431@N03/5611498895/in/set-72157626376005130/lightbox/





Although my testing wasn't as scientific as the others, I could comfortably say that in real world usage and in bright light with a red top, I am very pleased with the results.


Canon MK IV: 70-200mm f/2.8L IS II @f/4, 1/3200sec, ISO 200, CPL (No post processing and No cropping)


I started at 200mm and I zoomed out slowly to 70mm as my friend, the Skier was approaching me.














































Thanks for viewing!


C&amp;C always welcome!


Rich