Lens Focus Adjustment Tool for Digital SLR Cameras Alignment Ruler Folding Card

This is an essential tool when you need ideal focus when shooting with a shallow depth of field. ■Size: 19 12.3cm. ■How to use. Set your lens to the widest aperture and shallowest depth of field. Autofocus on the crosshair in the center of the ruler and take the photo.

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