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PCNS Labnotes Dec 2007
(requires a high resolution display of at least 1280 x 1024)
(wide aspect monitors may distort the images)

Issue:  Bill, one of my customers, has an IBM Thinkpad X61 laptop.  This model features a 12.1" Screen, of 1024 x 768 resolution.  This is commonly referred to as XGA resolution.  He has the IBM Media base, which allows a large monitor to be connected to it.  He has a 20" flat screen monitor, capable of displaying 1600 x 1200 resolution.  On the large monitor he arranges his Desktop Icons.  Program file icons and commands are located on the top left of the screen, going down the left side.   Towards the bottom he arranges Data files in groups of three.  He arranges by extension, so there are groups of Word Documents, Excel Worksheets, PDFS, and Visio Drawings accordingly, as shown below:

Original 1600 x 1200 Pixels

When Bill undocks the laptop, the display reverts back to the Thinkpad's 12.1" screen.  Bill is upset when all of the arranged Icons he has set above are jumbled and disorganized.   What happens after going to the laptop screen:

Reduced 1024 x 768 Pixels

When Bill reconnects the large screen, he is disappointed to find the Icons are in just as much disarray:

Back to 1600 x 1200 - Icons Jumbled

Though we may play with this on a periodic basis, some of us adjust this more, who have laptop computers, and drive an external monitor which has different display characteristics from the laptop.  In many cases, the external display is much larger so it will afford the user lots of screen real estate to perform their work.  Why don't Desktop Icons stay in the same place when Bill changes screen resolutions between the large external display, and the smaller laptop display?   First a primer is in order.

Let's suppose our laptop is a mainstream laptop, with a built in resolution of 1024 x 768.   What do those numbers mean?  These numbers (1024 x 768) refer to a measurement of Pixels, in X and Y coordinates.  In this case 1,024 Pixels (x) Width by 768 pixels (y) High.   A large screen monitor, say a 20" Flat Screen, (we talking standard not a wide screen monitor) has a native resolution of 1,600 x 1,200 pixels of resolution.  All things being the same (specifically our monitor) when you change from 1024 x 768 pixels to 1600 x 1200 pixels, icons will be much smaller in 1600 x 1200 mode.  This is because you are making the playing field much larger.  Think of flying, and the pilot climbs altitude a few thousand more feet.  What happens - you see more square miles as you look down through the fixed size airplane window, but homes, cars, and roads look smaller.  Now imagine your Monitor is that fixed size aircraft window.  As you increase Pixels, images on the screen get smaller.  A larger monitor uses higher pixel resolution because the screen is larger, and the larger screen stretches the screen area compensating, somewhat, making Icons larger and more readable.

Scaled sizes of XGA versus UXGA

Why does a large screen monitor have to make Icons smaller?  Put it this way, before high definition televisions, as you upgraded your old glass style Television, say you went from a 19" screen to a 30" TV, images on TV got larger, but the picture coarsened, especially if your viewing distance from the TV did not change.  This is because in standard broadcast/cable Television, the 525 Scan Lines must remain constant so we can view the broadcast signal.  As the picture tube size increased, scan lines became visible.

When you drag, move, and group Icons while in high pixel mode (on the 20" screen), and then you change to low resolution, Windows makes a mess of your icons, because it rearranges all the icons so you can see them on the smaller display field.  This is by design.  Why doesn't Windows put Icons back when switching from High to Low resolution like we might expect?

Consider a practical standpoint - suppose you had a completely full parking lot, 1600 x 1200 feet in size.   You then reduced the parking area by 40% to 1024' x 768'.  Could you get the same number of cars in the smaller area (without crushing or stacking the cars?).

In Windows, when you change resolutions from very high to very low pixel setting, it's as if Windows zooms in on the desktop.  Icons, taskbar, and desktop items grow larger.   That's the basic purpose of going with lower resolution - so we can makes items more legible and easier to read on our eyes.  Windows has to take into account the entire desktop area and resize it, not just the icons occupying the desktop.

But, Windows throws in some trickery - it rearranges the desktop icons which would have been hidden off the screen, so you can locate them, and in the process it tries the best it can, but at times, it scrambles them.   The goal is to make your Icons available when lowering display resolution.  What would be the point - if by switching 1600 pixels to 1024 means some of your Desktop Icons would disappear off screen, is that such a good idea?  If you had 45 Icons on a 1600 Pixel desktop and expected Windows to put them in the exact order and groupings when reducing screen resolution by 40% then the Icon sizes shrink dramtically.  That would defeat the purpose of lowering your screen resolution.  Instead of Icons getting larger (to be easier to read) they would get smaller!  Here's an actual photo of the Dell C400, at 1024 x 768 Pixels of resolution (note you should view with the highest resolution screen possible to avoid side scrolling):

Normal display of Dell C400 at XGA resolution

Closeup View:

Normal display of Dell C400 at XGA resolution

Now if Bill had his way, and wanted all icons on 1600 x 1200 pixels to line up correctly on a Pixel landscape that is 40% smaller, this is how our Icons would look on our Dell Laptop.  I am overlaying the Dell Display with the Adobe Illustrator image, zooming down the image to fit the screen, so this is an approximation.  What we're finding is the Icons would be fairly miniscule - you might need reading glasses to see them, and this would not be a mainstream notebook.  You should resize your Browser window so the diagonal image (from top Left to bottom right) should measure about 12", to match the actual size of the Dell Display.

C400-superimposed UXGA Result

Closeup View:

C400-superimposed UXGA Result - Actual Size

Even if you were to use Microsoft's Shell Extension Addin Layout.dll, Save/Restore Desktop Icon Positions, this function can only restore to the confines of the current pixel resolution.   What makes this hard to swallow for laptop users is they position their Icons on the high resolution display, and expect Icons to be in the same place when the undock their laptops, relative to the smaller screen.  This of course results in a jumble of icons.   For maintaining consistent Icon positions on the desktop on both the small and large display, the user needs to do the Icon arranging on the smaller, lower pixel monitor and then Saving the Icon Positions with the Shell Extension Option.

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