Table of Guide Numbers
Wide¹ 24mm 28mm 35mm 50mm 70mm 85mm 105mm
Built-In K-01/K30 ✗ ✗ 12 ✗ ✗ ✗ ✗ ✗
Built-In K20D/K-5 ✗ ✗ 13 ✗ ✗ ✗ ✗ ✗
Pentax AF200FG 15 ✗ 20 ✗ ✗ ✗ ✗ ✗
Tumax DSL28AF² ✗ ✗ ✗ 22 ✗ ✗ ✗ ✗
Metz 24 AF-1 ✗ ✗ ✗ 24 ✗ ✗ ✗ ✗
Promaster 5250DX ✗ ✗ 24 ✗ ✗ ✗ ✗ ✗
Tumax DSL88AFZ³ ✗ ✗ 20 24 30 ✗ 36 ✗
Pentax AF360FGZ 14 21 22 25 30 33 36 ✗
Tumax DSL98AFZ⁴ ✗ ✗ 23 28 35 ✗ 42 ✗
Promaster 7200EDF 20 ✗ 30 ✗ ✗ ✗ ✗ ✗
Promaster 7400EDF 13 20 ✗ 27 30 ✗ 34 37
Metz 44 AF-1 17 22 25 27 32 36 39 44
Promaster 7500EDF 14 23 26 30 34 38 40 42
Metz 50 AF-1 18 24 26 29 36 39 45 50
Metz 52 AF-1 20 26 30 32 38 43 46 52
Tumax DPT3AFZ⁴ ? 32 34 38 41 43 45 ✗
Tumax DPT5AFZ⁴ ? 35 37 40 43 46 48 50
Metz 58 AF-2 20⁶ 29 31 35 42 46 52 58
Pentax AF540FGZ 21 32 35 39 45 50 54 ✗
Sigma EF-610 DG⁵ ? 34 35 36 46 52 56 61


✗ indicates that this flash does not have this zoom step.
1 With built-in or included wide-angle diffuser.
2 Names include Tumax DSL283AF, DSL286AF, and DSL288AF; and Vivitar DF-183. The Metz 24 AF-1 is also related, but is listed with a slightly higher guide number.
3 And other variants, like the Metz 36 AF-5.
4 There are many variants of this flash on the market, some with slightly differing stated guide numbers. See table of OEM labels.
5 Both Super and ST models.
6 The 58 AF-2's wide-angle panel is more diffuse than that of the 58 AF-1, covering 12mm instead of 18mm (a whole 23° wider).

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