Hello Steve!

If I understand it well, you want to print an 8x10 sized picture on an A4 paper. If the situation is this, the process is the following:

-open the image in Photoshop
-select the zoom tool
-on the tool line click the Print Size button
-go to File-Print with preview
-Page setup set to A4 (landscape or portrait as you like)
-Center Image is signed but Scale To Fit Media should be empty!
-switch the print button and does not touch the printer's page setup parameters, the PS will set it automatically. If your printer is allow that, switch the "preview before printing" function.
-and print
In this process, as you see you don't have to deal with 8x10 size, the program will recognise and print it very punctually.
As a result you will get a print, with your exact 8x10 picture on a middle of an A4 paper. Thats all.

Regards
cleano

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