I wish I could tell you there was a perfect solution, but I'm afraid there is not.

You could connect the Motif XF to your computer via USB and use the "Yamaha Motif XF Editor Standalone/VST" - this allows you edit the Motif XF in Voice, Song Mixing or Pattern Mixing modes. When the Editor is Online it is a 1:1 representative of the Motif XF on the computer. Changes made in the software are immediately registered in the hardware and vice versa.

The other solution, (and forgive me but it is what I finally had to face myself), is reading glasses. The Editor might be a solution or you may find the default font too small as well, but you can adjust resolution of your computer. You cannot just put the XF screen as it isn't on the computer unless you use a camera over the screen.

In the future, with more and more time spent in front of backlit screens, eyesight will either evolve or we will have to have better ways to accommodate aging eyes... we are still first generation computer users, it will be interesting to see how this changes over time.

Other solutions... depending on what you are editing could be iPad... the current apps are light versions of the Editors... they are Voice Editor Essential, Multi Editor Essential, Performance Editor Essential.