Hi Jeff,
They take much more light than Phals.. But you will want to move them gradually so they don't get burned. My plants get a couple of hours of direct sun and dappled bright light the rest of the day. Morning or late afternoon sun is easier on the plant than mid day... Just like us at the beach!
The leaves of the Catts should be a nice bright/ light green and the Phals darker green ( more light makes the leaves lighter, less.. Darker)
Here' a Phal on the bottom and a Catt on top.