Folding Card Lens Focus Testing Tool Professional Calibration Alignment AF Adjustment Ruler Chart

Features This compact ruler allows you to determine if your lens is auto focusing accurately as it should It is an essential tool that is particularly useful when shooting with a shallow depth of field where focusing should ideally be spot on You can use this ruler to determine how off the focusing is for a particular camera lens combination and on supported cameras adjust the cameras auto focus settings to resolve thisOn for Nikon cameras this feature is known as AF Fine Tune For Canon and for Sony cameras its known as AF Micro Adjustment Please refer to your cameras instructions manual to see if this feature is presentSize 19 x 12 3cm How to use Set up the ruler Ensure both the camera and ruler are level exactly perpendicular and at the same height It is best to mount the camera on a tripod to do this Set the lens to the widest aperture to obtain the shallowest depth of field This will make it easier to determine if your lens is focusing accurately Auto focus on the cross hair at the center of the ruler then take a photo Inspect the photo to see if focusing is accurate It is recommended that you do this on a computer since you will be able to see better on a bigger screen If focusing is accurate the 0 on the ruler should be the sharpest point on the image and the other numbers get blurrier as you move away from the 0 If any number above the 0 is clearer then your lens is backfocusing Otherwise if any number below the 0 is clearer then your lens is fr