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[Q] Screen digitizer below standards? No handwriting?

OP dingdonggggg

2nd February 2012, 09:09 PM   |  #1  
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Can anyone enlighten me on the performance of the screen digitizer.

I have been testing several note taking applications on my TFP. Although I have lousy handwriting the TFP makes it even worse. At first I blamed myself and the rather clumsy big tipped stylus and to improve the results I downloaded Touchscreen Tuner. A nice application but minimal improvement.

Then I also noticed it is impossible to draw accurate on the TFP.
A straight horizontal or vertical line is possible but when you try to draw a straight diagonal line it becomes a wave line. Now I really got worried. Maybe my drinking habits had given me this unsteady hand. So I got out a ruler and drew a diagonal line along it. I was relieved that I could continue drinking but what a shock to see the result. Again the diagonal line turned out as a wave line. (See the screen shot)

It turns out the grid of the digitizer is much too widely spaced. I estimate the distance between grid points at about 5 millimeters. And apparently the algorithm to interpolate between the grid points is so insufficient that a contact on the digitizer between two grid points is regarded as a contact with the nearest grid point. The algorithm doesn’t calculate a point in between.

Another way to see this is when you pick up an icon on the home screen and slowly drag it diagonally across the screen. It will not follow your finger or stylus smoothly but it will sway from left to right and stay behind a bit and then catch up again.

A big plus for the TFP for me was the possibility to accurately draw and take notes while working in the field.
As it is advertized and showed by Asus in promotional videos.
That is also what the Notes application was designed for.

Again I am afraid that Asus has (next to GPS, Wifi/BT issues, performance and screen faults) promised us to much goodies to be true.

Does anyone have a solution to this shortcoming or maybe can test if they can reproduce my findings. Maybe it is a malfunction in my TFP.
Please let me know your solutions or findings.

By the way. I also tested a HTC Sensation, a HTC HD and an Ipad 2. On these devices it is perfectly possible to draw a perfectly straight diagonal line.
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2nd February 2012, 09:27 PM   |  #2  
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Seems the behavior is the same on my TFP, except that I tried drawing the diagonal with my finger and it came out a lot straighter than your screenshot. Not nearly as straight as horizontal and vertical lines though, but less waves that what you're showing.
2nd February 2012, 09:33 PM   |  #3  
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I used a Belkin stylus.
To draw the line I used the edge of a magazin.
I tried to apply equal presure and speed while drawing.
The issue is best seen in a diagonal line under 45 degrees.
3rd February 2012, 12:06 AM   |  #4  
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There is an app on the market to tune the touchscreen for this and Galaxy Tab, it helps a ton. Touchscreen Tune I think its called.

It is $5 though but with the app, good freewriting application and a decent pen, handwriting is a lot easier.
3rd February 2012, 02:48 AM   |  #5  
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Quote:
Originally Posted by agentdr8

Seems the behavior is the same on my TFP, except that I tried drawing the diagonal with my finger and it came out a lot straighter than your screenshot. Not nearly as straight as horizontal and vertical lines though, but less waves that what you're showing.

It largely depends on the speed you draw it. If you go really fast its pretty straight. Go really slow and its wavy as hell
3rd February 2012, 04:30 AM   |  #6  
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Maybe I am drunk....

The finer the stylus the wavier the line. Used my finger, no waves.
3rd February 2012, 06:12 AM   |  #7  
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Use the application mentioned above....
3rd February 2012, 06:31 AM   |  #8  
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I had a jot pro with a similar problem, except my writing varied greatly based on pressure. If I pressed down hard enough it would write like you would expect, but otherwise it did some crazy stuff. Might just be that particular stylus though
3rd February 2012, 07:00 AM   |  #9  
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Quote:
Originally Posted by oblomov

There is an app on the market to tune the touchscreen for this and Galaxy Tab, it helps a ton. Touchscreen Tune I think its called.

It is $5 though but with the app, good freewriting application and a decent pen, handwriting is a lot easier.

Quote:
Originally Posted by Striatum_bdr

Use the application mentioned above....

OP mentioned he tried this, no edit to original thread
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3rd February 2012, 08:53 AM   |  #10  
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Quote:
Originally Posted by redandblack1287

I had a jot pro with a similar problem, except my writing varied greatly based on pressure. If I pressed down hard enough it would write like you would expect, but otherwise it did some crazy stuff. Might just be that particular stylus though

I've got the same experience with the Wacom Bamboo Stylus.

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