Re: Closed loop system
Closed loop refers to working within limited constraints of calibration and workflow based upon your current hardware, with no means of correcting for the introduction of new input types or hardware, or outputing to unknown devices. For example, if you shoot with one camera, use only one computer and one software package, and of course only one printer.... you could create a closed loop calibration easily. After a little trial and error, you will have it all down pat. Every picture you produce will look great. Yet, let me introduce a new type of image to you, or maybe swap out your printer and see what happens.
However, most ventures today strive for an open-loop calibration/workflow. In this scenario, we create profiles & calibrate each piece of equipment to known standards. We then work within defined color spaces. All this is done so that we can generate intermediate or pre-final output that is usable across other platforms. As long as we tell others the proper color space to view the image in, and as long as their equipment is calibrated, the resulting output should be very close to what we intended.
By todays standards, closed-loop is bad, open-loop is good... with only a few exceptions.