Problem resizing when printing from C1 to Epson R2400?

I want to print from Capture 1 to my Epson R2400.

After selecting the printer from the menu at the top of the C1 print dialog, I have the following problem with image size on the A4 paper I'm using.

I select Print Settings/Preferences/Page Layout.

I then select Reduce/Enlarge Document, and select By Percentage.

I then reduce the image to, say, 50%.

But, nothing happens to the image on the screen. It still occupies the edge to edge of the A4 paper area.

If I print using Photoshop CS6, in this dialog the image area is visibly reduced when I change the % size.

Am I doing something wrong?

Thanks.

D.