A door-knocker at an entrance to Italy’s Central Military Library on the Via Venti Settembre in Rome. Picture taken Oct. 7, 2015. Nikon D7100. RAW. Sigma 70.0-300.0 mm f/4.0-5.6. 1/1250 sec. f/8. ISO 500. 240.0 mm (DX 360.0 mm). Click on image to enlarge and see the photographer in the reflection.