# Dell E1910: Is the diagonal measurement of the Viewable Area 19“ or 18.5”?

I am planning to buy the Dell E1910 monitor.

The data in various reviews are misleading - Dell website says it is 19" but some other review sites say it is 18.5".

What is the actual viewable area measurement? 18.5" or 19"?

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Dell's specifications give the panel size as "19-inch (482.6 mm viewable area)". The metric value corresponds to exactly 19 inches. They may be cheating with the conversion, but if the viewable area turns out to be 0.1 mm less than 19 inches, you would have a legitimate grievance that Dell is publishing inaccurate specifications.

We can cross-check with the pixel pitch, which is listed as 0.2835 mm with a native resolution of 1440x900. sqrt((1440*0.2835 mm)^2 + (900*0.2835 mm)^2) = 18.95 inches. Not exactly 19, but a lot closer to 19 than 18.5.

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"18.95" is exactly what I was looking for. Thanks a lot for the pixel pitch explanation. +1 – user57813 Jan 28 '11 at 14:33
Does "pixel pitch" mean the size of a single physical pixel element at native resolution? So when you multiply by the native res width and height you get actual width and height? – user57813 Jan 28 '11 at 14:34
Pixel pitch should be the spacing of the pixels (including any gaps between them). That is, the distance from the center of one pixel to the center of the adjacent pixel, for example. So the calculated area should be accurate, give or take a single pixel-gap or two at the edges, assuming that the pixel pitch specification is accurate. – coneslayer Jan 28 '11 at 14:48

It's neither, because no one can make something that's exactly 18.5" or 19" across. The "correct" answer will vary from monitor to monitor, change continually, run to dozens of digits, and be impossible to measure. To how many significant figures do you want an approximate answer? To two significant figures, I expect it's 19". To three significant figures, I expect it's 18.5".

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Oh. I didn't know it varied from monitor to monitor. An approx idea of whether its closer to 18.5" or 19" is what I want to know. – user57813 Jan 28 '11 at 12:06
You really thought that every monitor had a screen that is, say, 18.5436468376586395778369784532964364" across, and there wasn't perhaps one that was 18.5436468376586395778369784532964365" instead? You have a slightly over-optimistic view of manufacturing tolerances. – Mike Scott Jan 28 '11 at 12:08
It's probably closer to 18.5", if that's what the reviews are saying. When a manufacturer (or anyone) says 19", they mean 'between 18.5" and 19.5"'. If they actually mean it's very close to 19", they would say 19.0", or even 19.00". – Mike Scott Jan 28 '11 at 12:10
Manufacturing tolerances of .5 inches would be a bit much. – Daniel Beck Jan 28 '11 at 12:13
@Mike.. I am no expert in manufacturing.. but, for something that measures around 19", 0.05" error is okay. Definitely not 0.5". If 0.5" error supposed to be expected, then DELL doesn't know what its doing. I would accept 0.5" error for something that measures in hundreds of inches. – user57813 Jan 28 '11 at 12:24