The internal-focus tag has no wiki summary.
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What is the benefit of an internal focus lens?
The "IF" in Pentax DA★ 200mm f/2.8 ED (IF) SDM stands for "Internal Focus". I know what this means: the lens doesn't change in size as I focus. (And it's true; it doesn't.) What's the point of this, ...
2
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2answers
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How to check if Nikkor lens has IF feature?
The specification for the lens says that the Nikkor 18-105mm ED VR has the IF feature. However, the local market product label doesn't advertise this feature. How can I make sure that the IF feature ...
