Using coins for scale is discouraged as it will require people unfamiliar with them to look up the dimensions or guess, both of which defeat the purpose of the object in the first place. Coins can also reinforce a geographical bias, and some coins' designs are copyrighted.
Ideally, a photograph should include a ruler with the subject (example) or an added scale marking.
SI ("metric") units are the most commonly used worldwide (see meter and centimeter).
Rare earth ore, with a cent for size comparison Source: [http://resourcescommittee.house.gov/subcommittees/emr/usgsweb/photogallery/ US Government] {{PD-USGov-Interior-USGS-Minerals}}
Berkas ini mengandung informasi tambahan yang mungkin ditambahkan oleh kamera digital atau pemindai yang digunakan untuk membuat atau mendigitalisasi berkas. Jika berkas ini telah mengalami modifikasi, rincian yang ada mungkin tidak secara penuh merefleksikan informasi dari gambar yang sudah dimodifikasi ini.