Have played with my POP3 for about 2 months now and noticed that the calibration is sometimes off. Not a lot but enough to bother me. After reporting in this forum I was advised to calibrate the scanner after using it for 30 minutes. “Using” means the scanner need to be scanning, not just powered on.
Then I did the following test using a plywood board 123 x 64 x 17.6 mm in size as the object. The steps and results are as follows :
- do a dummy scan for 30 min. Calibrate immediately. Scan immediately. Average error +0.06
- switch off the scanner for 30 min allowing it to completely cool down. Scan. Average error +0.13
- do a dummy scan for 30 min. Scan immediately ( NO re-calibration ). Average error +0.07
- Let it cool down. power it on for 30 min, NO scanning. Then scan. Average error +0.13.
- Let it cool down again, do a dummy scan for 30 min. Scan immediately. Average error +0.06
It appears that the scanner does need be warmed up to the temperature at which calibration is done to achieve maximum accuracy and effective warm up does require the scanner to be working, not just powered on.
The obvious problem is that the scanner need be warmed up for 30 min before each use. Just wondering if there are less time consuming ways to achieve the same result.