how do you conert asa to din?

-- Bill Holton (binbrook@aol.com), November 27, 1999

Answers

DIN -ASA TABLE

DIN	ASA
6	3
7	4
8	5
9	6
10	8
11	10
12	12
13	16
14	20
15	25
16	32
17	40
18	50
19	64
20	80
21	100
22	125
23	160
24	200
25	250
26	320
27	400
28	500
29	640
30	800
31	1000
32	1300
33	1600
34	2000
35	2500
36	3200
37	4000
38	5000
39	6400
40	8000

DIN stands for Deutche Industrie Norm. Film speed doubles every 3 degrees, it is a logarithmatic scale.

ASA stands for American Standard Association. This is a arithmetric system. Film speed is proportional to ASA number. Each step increases by the cubic root of 2= 1.25, two steps by 1.6, hence the number ASA 125, 160, 250, 320 ETC.

Old British stand BS number = ASA number.

The International Standard Organization ISO number is a combination of ASA/DIN.

-- martin tai (martin.tai@capcanada.com), November 27, 1999.