Photo tips
How to photograph a coin
NumisPair works with ordinary phone photos. A few habits make the results even better.
Obverse first, then reverse
Take the obverse first. Then turn the coin over in the same spot and take the reverse. On the desktop, for bulk processing, NumisPair uses the order the photos were taken to pair them.
A grey background works well
A plain grey surface suits most coins: cloth, card or paper. Patterned or busy surfaces make the edge harder to find.
Darker coin, darker background
The camera sets its exposure for the whole picture. On a darker background a dark coin comes out brighter and shows more detail. Bright silver and gold coins do well on mid grey.
Fill the frame
One coin per photo, filling most of the picture, with the whole coin in view. Keep it roughly in the middle.
Soft, even light
Daylight from a window, or a lamp off to one side. Turn off the flash, which flattens detail and causes glare.
Hold the phone flat
Straight above the coin, so it looks round rather than oval. Up close, the NumisPair camera switches to the phone's macro lens by itself, like the Camera app. If it won't focus, lift the phone a little. Resting your elbows on the table helps keep it steady.