Canon EOS M Basic Instruction Manual page 145

Detaching the Lens
About Zooming
Do not look at the sun directly through any lens. Doing so may cause
loss of vision.
If the front part (focusing ring) of the lens rotates during autofocusing, do
not touch the rotating part.
The focus preset function of some lenses cannot be used with this
camera. Also, Power Zoom cannot be used even if you attach a lens
featuring the Power Zoom function, like the EF35-80mm f/4-5.6 POWER
ZOOM.
Lens Focal Length (Image Conversion Factor)
Since the image sensor size
is smaller han the 35mm
film format, it will look like
the lens focal length is
increased by approx. 1.6x.
Example: An 18-55mm focal length would be equivalent to an approx. 29-
88mm focal length on a 35mm camera.
Attaching and Detaching a Lens
While pressing the lens release
button, turn the lens as shown by
the arrow.
Turn the lens until it stops, then
detach it.
Attach the rear lens cap to the
detached lens.
To zoom, turn the zoom ring on the lens
with your fingers.
If you want to zoom, do it before
focusing. Turning the zoom ring after
achieving focus may throw off the
focus slightly.
Image sensor size (Approx.)
(22.3 x 14 9 mm / 0.88 x 0 59 in.)
35mm image size
(36 x 24 mm / 1.42 x 0.94 in.)
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