A resource for collectors, metal-detectorists and students
Coin Photography
Set-Up
Simply put, ‘set-up’ is the way the camera/smartphone and the coin to be photographed are physically prepared and arranged. At its simplest (and most unsatisfactory), it is pointing the hand-held camera at the coin and pressing the shutter. This approach is invariably unsatisfactory for the following reasons.
The coin is very unlikely to be truly parallel to the focal plane of the camera. This results in a round coin appearing oval, and the letters of the inscription appearing to vary in height. It is one of the most common faults encountered with images uploaded to the UKDFD, and one of the most difficult to rectify via image-processing.
It is virtually impossible to create matching (same size/same shape) images of obverse and reverse. This is another very common issue with images uploaded to the UKDFD. Provided that the difference relates solely to size, it is relatively easy to rectify via image-processing.
Poor focus may occur due to camera-shake. To some extent the effect of this may be lessened by AI technology, but this is less than perfect and not necessarily available on lower specification devices. When it occurs, it is impossible to rectify images satisfactorily.
No account may have been taken of the background. Unsatisfactory backgrounds can ruin otherwise technically sound images. Although they can be removed via image-processing software, it can be very time-consumimg.
Little or no account has been taken of the lighting. There are many aspects of lighting that affect image quality, some of which cannot be corrected by post-processing. The subject is covered in depth in the section entitled 'Lighting'.
Any loose foreign matter on the coin has probably not been removed. Depending on its extent and location, it may or may not be possible to 'remove' foreign matter on images by image-processing. It is surprising how quickly dust settles and surfaces become soiled.
The majority of the shortcomings identified above can be avoided by the simple expedient of using a tripod. When photographing a coin, the best configuration is to place it on a horizontal platform, vertically below the camera/smartphone, such that it can be illuminated from above. A set-up similar to that shown on the adjacent photograph is recommended. Here, a small piece of plywood has been used to make an extended platform at the top of the tripod to support the smartphone (a camera would be attached directly). A second platform, to support the coin, is made of clear glass held in a grooved plywood holder. A plastic clip is screwed to the holder to allow it to be moved up and down the stem of the tripod. The use of clear glass eliminates unsightly external shadows (see 'Lighting' section). For safety reasons, the side and back edges of the glass should be ground or taped (as illustrated). A third plywood platform with a similar plastic clip is provided to support the chosen background (here a sheet of white paper).
The remaining point to stress in respect of set-up is the need for scrupulous cleanliness. Immediately before taking a photograph, the glass platform should be carefully cleaned and the coin lightly brushed. The camera lens will also need periodic cleaning, and the background should be regularly checked for marks, and replaced as necessary.
Tip
When photographing a button, use a short length of metal tube to support it, just wide enough and deep enough to accommodate the loop with a little clearance. This permits easy adjustment of the squareness of the front, and ensures that the back and front of the button are the same size on the images.