Set AF mode to
AF-C
a1 - AF-C priority set to focus during testing. Release preferred for general photography.
a3 - Set to
OFF.
a6 - Number of viewfinder focus points =
11 (optional)
f5 - Assign AEL/AFL button to
AF lock only.
I choose the number of auto area focus points based on the requirements of my subject.
· 1 point for static or slow moving objects. (preferred)
· 9 points for predictable direction moving subjects without background clutter.
· 21 points for erratic moving subjects (like hummingbirds), that only fill a small portion of the scene.
With this AF set-up, keep your shutter button half pressed so the lens continuously adjusts focus until you actually fully depress the shutter. Focus and re-compose is accomplished by pushing and holding down the AFL button
after subject focus is achieved.
To fine focus the camera/lens, try Dot-Tune 1st;
If Dot-Tune doesn’t satisfy you, the complete fine focus process is listed below;
What is the best way to use the Micro Focus Adjustment?
The question is simple enough, but the answer really depends on the lenses you're using and the way you use them. The point of focus can be adjusted up to +/- 20 steps in 1-step increments. Also in both cases, any adjustments you make apply only to the specific camera body in question; lenses themselves are never modified by the camera's AF micro-adjustment settings. The amount of focus adjustment per step is proportional to the maximum aperture of the lens, with the goal being to increase the precision of the adjustment with large aperture lenses since they have a smaller depth of focus. With all that as a preamble, here the procedure for selecting and using an AF micro-adjustment setting:
- Mount the camera to a sturdy tripod.
- Position a reference target for the camera to focus on. The reference target should have sufficient contrast for the AF system to read, should be flat and parallel to the camera's focal plane, and should be centered with respect to the picture area.
- Print out either this Siemens Star Focus Chart or this Focus Test Chart on regular letter size paper. You can print it on a laser printer or inkjet (doesn’t really matter). Make sure to print on regular paper, not anything glossy like photo paper.
- Scotch tape or some other adhesive material to keep the focus chart on the wall.
- Lighting should be bright and even.
- Camera-to-subject distance should be no less than 50 times the focal length of the lens. For a 50mm lens, that would be at least 2.5 meters, or approximately 8.2 feet.
- Set the lens for AF and the camera for One-Shot AF, and manually select the center focusing point.
- Shoot at the maximum aperture of the lens via manual mode or aperture-priority AE, and adjust the exposure level if necessary to achieve an accurate exposure of the reference target. Use a low ISO setting to reduce noise.
- If the lens has an image stabilizer, shut it off.
- Use a remote switch and/or the camera's self-timer to release the shutter. Use mirror lock as well.
- Take three sets of images at micro-adjustment settings of -5, 0 and +5, i.e, three consecutive images at -5, three consecutive images at 0, and three consecutive images at +5. Then take a live view image for comparison.
- Examine the resulting images on your computer monitor at 100% pixel magnification and compare each image to the live view image.
- Take additional sets of test images at different micro-adjustment settings if necessary until the sharpest image is achieved and most closely matches the live view image.
- Save the corresponding micro-adjustment settings in the camera.
Here are a few additional precautions to observe:
• Do not attempt to autofocus on an angled chart, because doing so will degrade the consistency of the camera's focusing measurement. Keep in mind that the camera's AF sensor is comprised of multiple pairs of linear pixel arrays. If you attempt to autofocus on a single line in an angled focusing chart, only a few pixels from each active pixel array will "see" the target. Ideally, the contrast in the reference target should cover the entire area of the camera's center focusing point, and the reference target should be perfectly parallel to the camera's focal plane.
• For best results, manually set the focus on the lens to infinity for every exposure before allowing the camera to autofocus the reference target.
• Expect some minor variations in focusing accuracy within each set of three test images, even though they were all taken at the same micro-adjustment setting. This is completely normal, and is due to the tolerances of the camera's AF system.
• Expect smaller micro-adjustment settings to have a greater effect with telephoto lenses, and vice versa for wide-angle lenses.
• If you are attempting to set micro-adjustments for a zoom lens, it is important to realize that the camera's setting may only be accurate for the focal length setting you test. Test at three different focal lengths, short, long and in the middle then average the three results for the setting to use and retest to compare image sharpness.
• Some cameras and some zoom lenses may require more sophisticated calibration than the in-camera AF micro-adjustment settings can provide. In such cases, it may be necessary to have calibrations performed at a Factory Service Center.
HTH
Jim
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