Canon EF 17-40mm f/4L USM Instruction page 10

10. Close-up Lenses
(Sold separately)
Attaching a 500D (77mm) Close-up Lens
enables close-up photography.
The magnification will be as follows:
• Can be used at the 40mm end (magnification
0.30x - 0.08x)
• Close-up Lens 250D cannot be attached
because there is no size that fits the lens.
• Manual focusing is recommended for accurate
focusing.
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