Canon 24-105mm is L series lens

[john crossley]

Well, looking at the test shot above Lee, I would say that your lens was front focusing. A really quick guide to Micro-Adjusting is as follows:

First you need you need to set the camera on a tripod and place the target (black print on white paper) a minimum distance of 50 x the focal length, from the camera. (For a 50mm lens you would need a distance of 2.5 meters and a 500mm lens would require 25 metres). If you are calibrating a zoom, set the lens to the focal length you use most often. The target also needs to be parallel to the camera sensor.

Set the camera to aperture priority and set the lens to its maximum aperture. Also switch off any image stabilisation.

For front focusing lenses take a series of shots at 0, +5, and +10 and then examine the images to see which gives the sharpest result. If +5 gives the best result, take another series of shots at +3, +5 and +7. Again examine the results for the sharpest image. Assuming +7 was the sharpest, take another set of shots at +6, +7 and +8. If the +6 image is the sharpest then set the micro adjustment to +6 for that particular lens.

NOTE: this is just a rough guide to micro-adjusting a lens. The actual amount of compensation and the number of test shots you take is entirely up to you.

[Nemesis]

Cheers for that all, I think I may have cracked it by doing a settings reset on the body, no idea what i had set but it seemed to have knocked everything out....