The i1 devices are known to be sensitive to low powered USB ports. Those port are common on MacBook and other laptop computers. Using these devices (even the separately powered i1 iO) with a low power USB port result in the following reported behavior:
- Blocking device : device starts calibration but fails, the light in the i1 stays on. No report in the software or device-not-found error.
- Beep(s) in i1 iO : measuring works until at a certain point the i1 iO starts sounding the beep several times and then the software reports and error or even the i1 iO driver crash and taking the software down.
These problems are usually solved by selecting another USB port or using a powered USB hub.
The device is delivered in several revisions. There are significant behavior differences between rev. A and rev. D. The revision number can be found on the serial number tag of the device.
- Rev. A : When the difference between neighboring patches is small (e.g. linearization strips) then this revision is known to merge patches together and reporting less patches to the software than actually measured. This results in a reading error in the software.
- Rev. D : When the patches are not clear (e.g. fast movement or low printing resolution) then this revision is known to generate more patches than actually are printed. This results in repeated patches with the same color and thus a shift in the patch sequence. This error is easily detected in an ICC or device-link target but can be undetected in linearization strips when there is little difference between neighboring patches.
A common cause for reading- and calibration errors using the iO device is improper installation of the i1 in the holder. The head of the i1 should firmly be pushed into the holder until a click sounds. During calibration there should be almost no stray light visible, if there is; check the head positioning.