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08-01-2021, 10:13 AM   #1
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Convertor quickie

So, how is the 7.5x calculated with a 1.4 RC and 300mm used together?


Last edited by mysterick; 08-02-2021 at 10:31 AM.
08-01-2021, 10:36 AM   #2
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Are you referring to the erroneous information read out by older versions of exiftool?
08-01-2021, 11:56 AM   #3
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I am a bit confused as well. the 7.5x is a bit of a mystery to me as there is no context for where it came from. The only thing I could think of was that it is similar to the numeric multiplier used by binoculars and spotting scopes and at 420mm (300mm + 1.4x converter) would give something kind of close (about 8.4) but that still isn't 7.5
08-01-2021, 04:22 PM   #4
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If a A 56mm lens were considered X1, then 300mm x 1.4 = 420mm and that 420mm divided by 56mm is 7.5. Maybe ??

08-01-2021, 08:31 PM   #5
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QuoteOriginally posted by Bob 256 Quote
If a A 56mm lens were considered X1,
Not sure I know anybody with a 56mm lens

But, Yes - an interesting question/number
08-02-2021, 06:06 AM   #6
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It's a mysterick mystery.
08-02-2021, 06:46 AM   #7
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Exactly!

08-02-2021, 07:03 AM   #8
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QuoteOriginally posted by mysterick Quote
Exactly!
Would be less of a mystery if you posted the source of this "calculation"
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