paper sizes
Jan. 17th, 2006 05:37 am![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
jinianI find from the Wikipedia article on paper sizes that the people who made the notebook paper I bought at the drugstore in an unguarded moment are not merely evil or mad. The 8"-by-10.5" paper size was apparently the standard U.S. government paper size for no few years, though the reason isn't exactly clear from the article. (I can guess what they mean by "Apparently this would enable discounts from purchase of paper for schools," but why would it do that?) My guess is that paper of that size was cheaper to start with, possibly because 8.5"-by-11" paper that was messed up in production could be retrimmed to the smaller size and sold by the paper company instead of pulped. The U.S. government went over to 8.5-by-11 paper during the Reagan era, a change which Wikipedia attributes to the prevalence of photocopiers, which didn't tend to have a paper cartridge dedicated to each strange size.
You may have known this already: A4 paper, which pretty much the whole rest of the world uses instead of letter, is based on a clever series of scaled paper sizes based on the ratio 1:sqrt(2), meaning that if you bisect the paper's long axis to make two half-size sheets, each of the daughter sheets has the same aspect ratio as the original. A3 sheets can be folded in half shortwise to make brochures the size of A4 sheets, and so on. A0 paper has an area of one square meter, giving it dimensions of 841mm by 1189mm. There are also B and C series in the international paper standard, both larger than A. That part was not well thought out; B is biggest, then C, then A, so when a country like Sweden chooses to extend the alphabetical scheme in a rarely-used fit of systematics you get size progressions like A4, E4, C4, G4, B4, F4, D4, H4, A3. While it's lovely that each of those is an area increase of 21/16, remembering the screwy order is not lovely at all.
My eyes started to glaze over when the article got to tables of dimensions, but I perked up at the PA series, which had been mentioned earlier. It's not actually in the standard bcause the standard-makers thought they had enough damned paper sizes already, thank you, but it's nifty in its way: In landscape orientation, it has the same 4:3 aspect ratio as the displays of traditional TV sets, most computers and data projectors. PA4 is therefore a good choice as the format of computer presentation slides. At the same time, PA4 is the largest format that fits on both A4 and U.S./Canadian "Letter" paper without resizing. Neat stuff.
You may have known this already: A4 paper, which pretty much the whole rest of the world uses instead of letter, is based on a clever series of scaled paper sizes based on the ratio 1:sqrt(2), meaning that if you bisect the paper's long axis to make two half-size sheets, each of the daughter sheets has the same aspect ratio as the original. A3 sheets can be folded in half shortwise to make brochures the size of A4 sheets, and so on. A0 paper has an area of one square meter, giving it dimensions of 841mm by 1189mm. There are also B and C series in the international paper standard, both larger than A. That part was not well thought out; B is biggest, then C, then A, so when a country like Sweden chooses to extend the alphabetical scheme in a rarely-used fit of systematics you get size progressions like A4, E4, C4, G4, B4, F4, D4, H4, A3. While it's lovely that each of those is an area increase of 21/16, remembering the screwy order is not lovely at all.
My eyes started to glaze over when the article got to tables of dimensions, but I perked up at the PA series, which had been mentioned earlier. It's not actually in the standard bcause the standard-makers thought they had enough damned paper sizes already, thank you, but it's nifty in its way: In landscape orientation, it has the same 4:3 aspect ratio as the displays of traditional TV sets, most computers and data projectors. PA4 is therefore a good choice as the format of computer presentation slides. At the same time, PA4 is the largest format that fits on both A4 and U.S./Canadian "Letter" paper without resizing. Neat stuff.
