Canon Macro Ring Lite MR-14EX Mode D'emploi page 16

Flash Setting Guide
This is a general guide to setting the flash angle for various magnifications
with a macro lens. Refer to the angle scale (15° increments) on the side of
the flash head and set the same angle for both flash heads A and B. The
angle specifications in the table below indicate the inner angle relative to
the flash head's standard position index (horizontal).
Lens
EF50mm f/2.5 Compact
Macro
EF50mm f/2.5 Compact
Macro
+Life-Size Converter EF
EF100mm f/2.8L Macro IS
USM
EF100mm f/2.8 Macro USM
EF100mm f/2.8 Macro
EF180mm f/3.5L Macro
USM
MP-E65mm f/2.8 1-5x Macro
Photo
EF-S60mm f/2.8 Macro
USM
14
Magnification
1:2
1:2.5 - 1:3
1:4
1:5 - 1:6
1:8
1:10
1:1
1:1.2
1:1.5 - 1:2
1:4
1:1 - 1:1.5
1:2
1:3
1:5
1:1
1:1.5
1:2
1:2.5 - 1:3
1:4
1:1
1:1.2 - 1:1.5
1:2 - 1:10
5x - 2x
1x
1:1 - 1:1.5
1:2
1:3
1:5
Flash Head Inner Angle
60° 45° 30° 15° 0°