Focus Tracking Optical Zoom LensesDid you know that you can estimate the optimal length of a new zoom lens as it will be about the same as the longest focal length of the optical design. For instance – if you have a 10 to 100mm (10X) zoom lens the length of the lens will be approximately 100 mm. If though you need to reduce the length of the zoom lens it can be done but you increase the complexity of the design and impact performance depending on how much you want the length reduced.

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