spacediver
2[H]4U
- Joined
- Mar 14, 2013
- Messages
- 2,715
Wanted to pick some brains here about an interesting challenge.
A large part of the WinDAS calibration involves adjusting parameters so that the image dimensions match specified values (in mm).
So for example, it may ask you to increase the horizontal size until the image is 474 mm wide.
I've found doing these measurements extremely tedious and time consuming, because of the parallax error issue. You need to ensure that your line of sight is perfectly centered the point being measured. You can easily see what I mean by doing the following experiment:
touch the screen with your finger, and try to line up the center of your fingernail with a point on the image (choose an edge of a displayed line). Now move your head around. Notice how the finger no longer lines up when you change your line of sight?
The solution I've been using for now is to hold a straight object, like a chopstick, against the screen, so that the end of the chopstick is flush against the screen, and centered on the point I'm measuring. I then use the chopstick as a line of sight guide and read off the measuring tape accordingly.
This is extremely tedious, however, and requires a lot of dexterity and flexibility!
I had another idea that might work. You'd have a clear plastic material with a fine grid structure printed on it, with millimeter markings - kinda like a "two dimensional" ruler. You would somehow attach this grid onto the screen so that it doesn't move. It doesn't have to be flush against the screen, but it would be better if it was.
You'd then be able to take measurements without having to hold a tape measure against the screen (which is actually the most tricky part of the whole process). You'd be free to move your body around so that your line of sight is matched up to whatever point you're interested in.
And, this would have an advantage for geometry adjustments. You could easily assess whether the lines are parallel to the bezels by using the grid as a reference.
Any ideas on where one could find such a plastic grid (or any other ideas on how to deal with this challenge)?
A large part of the WinDAS calibration involves adjusting parameters so that the image dimensions match specified values (in mm).
So for example, it may ask you to increase the horizontal size until the image is 474 mm wide.
I've found doing these measurements extremely tedious and time consuming, because of the parallax error issue. You need to ensure that your line of sight is perfectly centered the point being measured. You can easily see what I mean by doing the following experiment:
touch the screen with your finger, and try to line up the center of your fingernail with a point on the image (choose an edge of a displayed line). Now move your head around. Notice how the finger no longer lines up when you change your line of sight?
The solution I've been using for now is to hold a straight object, like a chopstick, against the screen, so that the end of the chopstick is flush against the screen, and centered on the point I'm measuring. I then use the chopstick as a line of sight guide and read off the measuring tape accordingly.
This is extremely tedious, however, and requires a lot of dexterity and flexibility!
I had another idea that might work. You'd have a clear plastic material with a fine grid structure printed on it, with millimeter markings - kinda like a "two dimensional" ruler. You would somehow attach this grid onto the screen so that it doesn't move. It doesn't have to be flush against the screen, but it would be better if it was.
You'd then be able to take measurements without having to hold a tape measure against the screen (which is actually the most tricky part of the whole process). You'd be free to move your body around so that your line of sight is matched up to whatever point you're interested in.
And, this would have an advantage for geometry adjustments. You could easily assess whether the lines are parallel to the bezels by using the grid as a reference.
Any ideas on where one could find such a plastic grid (or any other ideas on how to deal with this challenge)?