Screen Alignment/Sensitivity Resolved!!

[frozone]

I've seen a lot of churn about "Screen Sensitivity" settings, endless "Align Screen" issues, how a registry hack sometimes works, sometimes not, and I would like to definitively debunk a lot of bad advice.

First, changing the registry settings to numbers that worked for someone else is not the issue. The reason everyone's numbers are different is every digitizer is different (thus the need for alignment in the first place). Simply copying someone else's registry settings is not going to solve the problem.

Now about the numbers: there is nothing in this registry key that has anything to do with how *hard* you press the screen:

HKEY_LOCAL_MACHINE/HARDWARE/DEVICEMAP/TOUCH/CalibrationData

Here are some sample settings:

519,503 177,881 182,129 847,127 849,872

Notice that there are 5 sets of number pairs (519,503), (177,881), etc. These correspond to the 5 times you tap the screen in the windows “Align Screen” process. If your screen is a little out of alignment, these numbers are used to do a linear transformation to correct slight digitizer errors. For those that don’t know, a linear transformation can take a slanted screen and straighten it up. All straight lines are still straight after the transformation.

Now, here’s the problem. If the digitizer has been damaged and is not capturing straight lines in the first place, the screen alignment process won’t work. Curved or bending lines can never be “straightened” with a linear transformation.

Here’s a simple test to see if this is your problem. Open Notes, and with a stylus, draw a rectangular grid of horizontal and vertical lines. Use a credit card to make sure the lines are straight, and try and trace along the horizontal guidelines in Notes. If the digitizer lines closely follow your stylus, and are straight but a little angled, then Screen Alignment will solve your problems. If, like me, your lines are wavy, curve all over the screen, or at any location on the screen they “jump” away from the stylus in random ways, then you have a bad digitizer (a problem with Omnias), and you need to replace it. No amount of endless “Screen Alignment” will help.

If you have wavy lines, then it will seem like the screen is “insensitive” because where you think you are tapping the screen is someplace completely different. When you tap harder, you simply damage the digitizer more. Also, I’ve seen some pretty rough handling as users tried to work bubbles out of a screen protector, which can also damage the digitizer (ironic, I know, as you are applying it to *prevent* damageL). The best way to work out bubbles is to gently work them out with a rubber handled toothbrush. Don’t carry your phone in your back pocket either…

Now, the real fix (and it is really easy!) but you have to take your Omnia apart. I ordered a $10 replacement part (included shipping and all the tools to take your Omnia apart!) from here:

http://cgi.ebay.com/Touch-Screen-Digitizer-for-Samsung-Omnia-i900-Black_W0QQitemZ310145029986QQcmdZViewItemQQptZPDA_ Accessories?hash=item4836159762&_trksid=p3911.c0.m 14#ht_1276wt_939

Here are some great instructions for taking your Omnia apart (note the first one points out some differences between the i900 and the i910, the YouTube videos are of the i900):

http://www.samsung-omnia.org/samsung-omnia-how-to/i910-digitizer-replacement/msg57420/#msg57420

http://www.formymobile.co.uk/omniadisassembly.php

http://www.youtube.com/watch?v=ydNZTeHSmz0&feature=related

Once you replace the digitizer, do the Notes test again to make sure that the lines are “mostly” straight. If so, then all you need to do is a Screen Alignment to true it up, and you will be good to go.

How’s that for a $10 fix!! J My Omnia now works as good as new!!