Today’s Question: I am the digital chair for a camera club. We’ve calibrated our projector using a high-end calibration system using the club’s laptop. My question is this: when a guest speaker comes in with their own laptop, if we copy the projector profile from the club’s laptop to the presenter’s laptop will we get the proper calibration?
Tim’s Quick Answer: If you are using a digital connection (DVI) for your projector, you can achieve relatively consistent results among multiple computers, provided all other conditions (including the screen and ambient lighting) remain consistent. If you are using an analog connection (VGA), your results will be less consistent (or even wildly inconsistent) from one computer to the next.
More Detail: When you calibrate and profile a digital projector (just as with a monitor display), you are measuring the behavior of that projector in the specific context of the current environment. That includes the computer (and therefore the display adapter) being used to send information to the projector, as well as the screen being used, ambient lighting conditions, and other factors.
If you are using a completely digital connection (from the computer’s display adapter to the cable to the digital projector) the results will be much more consistent. Therefore, it is possible to get very good results with a single ICC profile shared among multiple computers.
On the other hand, if you are using an analog connection (via a VGA cable), the analog signal (and the conversion between digital and analog) may introduce significant variability from one computer to the next. In this situation I would recommend creating a profile for each computer that will be used with the digital projector.