Talk:ISO 7810

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[edit] Exact definition of ID-1?

Could someone with access to a copy of the actual standard please confirm the exact definition of ID-1, which is allegedly 85.60 mm × 53.98 mm (3.370 in × 2.125 in). These seem odd choices of values in either system of measurement and also overly precise, because ISO 216, where ID-2 and ID-3 come from, for comparison uses definitions to full millimetres and allows some variance. If ISO indeed uses these very four figures, why?

For me it looks like the actual size is 85.5 mm × 54.0 mm, was converted to the closest eighth of an inch (3+³⁄₈ in × 2+¹⁄₈ in), then the smaller size was converted back to millimetres with four significant figures (53.98 mm), but I do not see how 85.73 mm could become 3.370 in and subsequently 85.60 mm. The ratio of about 1.5857725 does not look like anything meaningful either, even when squared. Christoph Päper 21:45, 9 September 2006 (UTC)