I don't know how good that software is, but I just spent a day doing micro focus adjustment on my 9 lenses on a 6D using the technique described elsewhere using the EOS utility software and remote control via a laptop and usb cable. It makes an amazing difference in sharpness with subsequent improvement in contrast when the lens is wide open. For the 100-400 mm lens you would be adjusting focus at a distance of 16 ft. for min. and 66 ft. for max. zoom. It is mm/25.4mm/in. X 50 to get recommended inches divided by 12 to get feet. Of the 9 lenses I did this on, only 3 were spot on, an old first series 50mm F1.8; 24-105 F4L IS USM dead on at min. zoom and max zoom; and 135 F2L USM.
I used form ISO 12233 for the detail target. Set up up the camera and lens on a tripod at the recommended 50 times lens length. I put a spot light on the target to ease adjustment. I made certain the camera was exactly square and level with the target which you can do with a mirror or other technique. I would also turn off image stabilization on the lens. You use the remote selection in the EOS utility software. You select Live View. You then select manual selection of focus point as the center point and square up the live view square on the target as shown on the computer screen. Then select Maintain Zoom and 200 times and expand the image on the computer. Each time you select AF ON, the camera refocuses. There are marks below of < or >. You keep refocusing and repeating the selection and number of clicks until you are confident that you are right in the center of the focus adjustment selection. Write down your result. Some lenses you could see one click difference either way while others, there were a couple clicks and I would select the middle of the range.
Then set the micro focus adjustment in the camera. For each adjustment of >, you go above zero (or positive); for each adjustment of >, you go minus. Then verify your result with the lens. On those that I verified, I was right on. On my other L lens, a 70-200 F2.8L ii USM, I was back focused (<5 on both min. and max. mm).
I suspect you will find that you are dead on, but you will never know unless you test it. I found this to be a major pain until I became familiar with the process and went through 4 camera batteries doing the test repeatedly to verify the results to myself. This process demonstrated to me the quality of the better lenses for clarity and contrast as well as confidence now in the focus. Not often, but on occasion I noticed an old lens not accurately refocus the same. However, after I was done I had the impression that the lenses were focusing with less hunting in limited light due to better focus and contrast.
There are several other articles on-line dealing with this and other methods of performing micro adjustments. I believe this method to be the most precise.
)
