It's not particularly hard, it seems. Before I got my fancy LensAlign tool, I used a [url="http://www.focustestchart.com/focus12.pdf]cut-out paper chart[/url]. With my T1i body (which lacks the microadjustment feature) and that chart, it seemed myEF 100mm f/2.8<span style="color: red;"]LMacro IS USM was front-focusing a bit, while all my other lenses were ok. But, there was nothing I could do about that myself - lens and body would have had to go to Canon Service. Now, with my 7D andLensAlign Pro, I just tested my100mm f/2.8<span style="color: red;"]LMacro, and pretty close (though I may adjust it a bit). The only other lens I've tested so far - my EF 85mm f/1.8 USM - seems to be back-focusing a bit. These are only single test shots, as well. I really need to shoot 3-5 shots, obviously. I haven't done adjustments yet (having a 2 year-old daughter means not having long blocks of time!), but the procedure seems to be simple.