[CentOS] Simple scan in CentOS 7

I just installed C7 on a new computer and despite Simple Scan being installed as part of C7, I have not been able to get it to recognize my Canon scanner connected to a USB port. I did have it running on another computer with C7 so there should not be any inherent issues.

On a lark I installed gscan2pdf and sane-backends-drivers-scanners and sane-find-scanner found it:

found USB scanner (vendor=0x04a9 [Canon], product=0x1908 [CanoScan]) at libusb:001:010

I perused my notes for the old computer but did not see I installed any additional software to get it going but I might be wrong.

What have I missed?

Thank you.