SINCE 1828
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back focus

noun
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Definition of back focus

: the distance from the rear glass surface of a photographic lens to the focal plane when the lens is focused on a very distant object

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First Known Use of back focus

1868, in the meaning defined above

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Time Traveler for back focus

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The first known use of back focus was in 1868

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Dictionary Entries Near back focus

backflow

back focus

back-formation

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Cite this Entry

“Back focus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/back%20focus. Accessed 28 Jun. 2022.

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