Even after using a huey to calibrate my iMac, letting Photoshop take care of colour management, and disabling colour management in my Epson R800 printer, I am still getting prints that are too dark

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I'm assuming tht this is due to the fact that the iMac monitor is still too bright. This begs the following questions: as my iMac has a brightess setting, what setting should this be set at before calibrating with the huey? Or am I failing to do something wrong?
Any assistance would be helpful!
Onesimus