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NatCh · 07-17-2006, 02:01 PM

I've always interpreted PPI to be the same as DPI. I think they're "Pixels Per Inch" and "Dots Per Inch" respectively, so that ought to be the same.

Working with the pixel counts & PPI numbers I came up with this:
800/170 = 4.7058823529411764705882352941176
600/170 = 3.5294117647058823529411764705882

So, I figure the screen must be pretty close to 4.7 inches by 3.5 inches. (That's 11.9 cm by 8.9 cm for you metric users out there)

As a cross-check, I plugged that into the Pythagorean Theorem, and got a calculated diagonal measurement of 5.86 inches, which is pretty close to the 6 inch diagonal that Sony reports.

Unfortunately, I can't get a firm read on what the best size would be, my information suggests that the font sizes in the original document make a difference, and that you have to play with it a bit to get it just right.

However, I think that the screen dimensions give us a good place to start. If we made a PDF with 4.7X3.5 pages and little or no margins, that ought to be in the right neighborhood. We'll just have to tweak it once one of us MobileReaders gets some hardware to test on.

07-17-2006, 02:01 PM	#4
NatCh Gizmologist Posts: 11,615 Karma: 929550 Join Date: Jan 2006 Location: Republic of Texas Embassy at Jackson, TN Device: Pocketbook Touch HD3	I've always interpreted PPI to be the same as DPI. I think they're "Pixels Per Inch" and "Dots Per Inch" respectively, so that ought to be the same. Working with the pixel counts & PPI numbers I came up with this: 800/170 = 4.7058823529411764705882352941176 600/170 = 3.5294117647058823529411764705882 So, I figure the screen must be pretty close to 4.7 inches by 3.5 inches. (That's 11.9 cm by 8.9 cm for you metric users out there) As a cross-check, I plugged that into the Pythagorean Theorem, and got a calculated diagonal measurement of 5.86 inches, which is pretty close to the 6 inch diagonal that Sony reports. Unfortunately, I can't get a firm read on what the best size would be, my information suggests that the font sizes in the original document make a difference, and that you have to play with it a bit to get it just right. However, I think that the screen dimensions give us a good place to start. If we made a PDF with 4.7X3.5 pages and little or no margins, that ought to be in the right neighborhood. We'll just have to tweak it once one of us MobileReaders gets some hardware to test on. Last edited by NatCh; 07-17-2006 at 03:17 PM.