I use Aperture on both my MacPro with a 21" Apple cinema display and a 2012 MacBookPro with 15" display. When I put the displays alongside each other with both displaying the same picture I noticed a difference in the colours. One looked more yellow than the other, I forget which way round.
So I thought I'd better get them calibrated and purchsed a X-Rite i1 Display Pro calibration device and went through the calibration process on both computers.
Folowing this I ordered two 24"x16" poster prints and they arrived today looking a bit washed out and lacking contrast. I've used this print supplier before and have always been happy with the results so I suspected my recent recalibration has caused this.
Sure enough when I switch back to the old colour profile in the display prefs panel the monitor is much brighter and closer to the actual brightness and contrast of the prints received.
Is there a way I can use the calibrator to match the results I get from a print supplier? Or is it just a case of trial and error?
Also, I sell my pictures via a website and I've often wondered what is the ideal brightness level to use on my monitor when preparing pictures to match how they'll be displayed to people viewing them on their home computers, most of them aren't photographers and won't have callibrated monitors. If they're likely to have their monitors set to full brightness and I adjust my pictures with the monitor set to only half brightness (as the X-Rite calibrator suggests) then they could look over exposed on the customer's monitors.
Any help/suggestions on this topic much appreciated.