Infinity Frame was designed for my wife.  It contains 3 different parts - the main body and the inserts to hold the picture in place.  You can use the inserts as templates to cut the photos to insert into the frame.

I printed this in .3mm draft mode with 10% fill (Honeycomb).  Top and bottom layers should be set at 5 to avoid seeing the infill.  I used PETG gray material.