Chapter 14: the Proportion Wheel

Before you forget everything we just did, test your skill with the proportion wheel a few different ways. Remember to use your logical brain. If you’re getting confused, think: Is the number I’m looking for supposed to be larger or smaller than the number I’m starting with? Is the proportion I’m finding logical? Will it produce the result I want?

1. Find the proportion needed to reduce a 12″ x 16″ page to fit on 8.5″ x 11″ office paper.

First, remember that the live area of a sheet of office paper is effectively 7.5″ x 10″—you need to leave a 1/2″ margin all around to account for the limits of the photocopier or printer.
12″ reduces to 7.5″ at 62.5%.
16″ reduces to 10″ ALSO at 62.5%.
So, a 12″ x 16″ live area is exactly the same ratio as a piece of office paper, and you would reduce it at 62% (always round down for margin safety).

2. Find the percentage to fit 10″ x 15″ original art on a photocopied page that’s 5.5″ x 8.5″ (minicomics size). Don’t forget to leave a border clear so the copy doesn’t get cut off.\

Your printable live area on a minicomics-size booklet is 4.5″ x 7.5″.
10″ reduces to 4.5″ at 45%.
15″ reduces to 7.5″ at 50%.
So, a 10″ x 15″ live area will need to be reduced at 45% to fit on a minicomics-size page.

3. Find the percentage needed to reduce 12″ x 16″ original art to fit on a photocopied page that’s 7″ x 8.5″ (legal-paper minicomics size).

Your printable live area on a half-legal-sized digest comic is 6″ x 7.5″.
12″ reduces to 6″ at 50%.
16″ reduces to 7.5″ at 47%.
so, a 12″ x 16″ original live area will need to be reduced at 47% to fit in a half-legal digest mini.
4. Size up a reproduction size of 6″ x 9″ at 150%, and at 200%.
6″ x 9″ at 150% is 9″ x 13.5″.
6″ x 9″ at 200% is 12″ x 18″.

5. Size up a reproduction size of 2.75″ x 4.5″ at 150%, and at 200%.

2.75″ x 4.5″ at 150% is 4.125″ (4 1/8″) x 6.75″ (6 3/4″)
2.75″ x 4.5″ at 200% is 5.5″ x 9″.

6. Size up a reproduction size of 7.5″ x 10″ at 150%, and at 200%.

7.5″ x 10″ at 150% is 11.25″ x 15″
7.5″ x 10″at 200% is 15″ x 20″
7. You have [been asked to draw [another unclear line–correct for reprint?] a comic that will be reproduced at 6″ x 9″ and you want to draw it as big as possible on a 14″ x 17″ sheet of bristol board. What’s the largest live area you can work at with a minimum of a 1/4″ margin left around the edge of your bristol board?
First of all, figure out the largest live area you can use. With a 1/4″ margin all around, you’ve got a potential live area of 13.5″ x 16.5″.
Now, figure out the enlargement for 9″ to get to 16.5″. It comes out to 183%.
Figure out the enlargement of 6″ to get to 13.5″. It comes out to 225%.
You’ll have to choose the smaller of the two enlargement percentages in order to have the live area fit on the paper, so choose 183%.
So, size 6″ up by 183% to find the width of your live area. It comes out to 11″.
The largest 2:3 ratio live area you can fit on a standard sheet of 14″ x 17″ bristol is 11″ x 16.5″.
Bonus question from page 223: what percentage would you need to use to size up 6″ x 9″ reproduction size to 10″ x 15″ original size?

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