How to fix oval looking circles on your screen

[jovivier]

CALIBRATING FOR DIFFERENT SHAPED MONITORS

Most displays, especially CRT's, are not perfectly calibrated for their onscreen sizes. This error is generally inconsequential and can be ignored. There are, however, some cases where the vertical and horizontal errors can be different enough that there is noticeable distortion on the screen: for example, circles appear as ellipses. One common problem is with LCD displays larger than 17". The software drivers for the display can incorrectly report the monitor’s dimensions and a horizontal/vertical aspect mismatch occurs.

IRRICAD can compensate for these errors with two entries in the VCADD.ini file. If you installed IRRICAD to the default path, the VCADD.ini file is located in the Programs folder as follows:
C:\Program Files\AEI Software\IRRICAD Pro 10\

When you first open the VCADD.ini file you will see the following. The first two entries are for monitor corrections, the last two for solving memory conflicts:
[VCDefaults]
HorzCorr = 1
VertCorr = 1
NTSize =
NTBase =

In general, only one entry is required to compensate for the aspect error, but both can be used to calibrate the onscreen dimensions. The procedure to correct an aspect problem is the simpler approach.

To correct an aspect problem, do the following:
1. Start IRRICAD and draw a square, then do a “Zoom All”.

2. Use a ruler to measure the onscreen height and width of the square.

3. Divide the height by the width.

4. Exit IRRICAD.

5. Edit the VCADD.ini file with any text editor and change the value from "1":
[VCDefaults]
HorzCorr = answer from step 3
For example:
[VCDefaults]
HorzCorr=1.065

6. Save the VCADD.ini file and restart IRRICAD.