There is no single lighting technique that works best for every coin. I keep telling myself I should destroy all my coin photo pages because they only show coins that worked well for the lighting I was using that day. I seem to try something new every time I shoot coins with results varying from better to horrific. That is part of the fun.
The different factor each time is the coin.
Irrespective of whether you are doing
bulk photography (me, some coin dealers) or are seeking individually great results (doug), nothing seems to
work better than inconsistency.
For when I do use lighting, I use a Lumie day-light effect LED desklamp with an array of 96 LEDs that are big enough to photograph a
complete coin tray consistently - this is how I get my red-Abafil trays photographed:
http://andrewmccabe.ancients.info/RRC028.htmlThe
lamp is about 0.5 metres above the coin, offset at a slight angle so the light falls best on the foreheads, and with a white cotton cover (pillowcase etc.) to diffuse the light.
Still, even for these I need to adjust each coin individually afterwards; sometimes the bronzes need more light contrast and the silver may be too bright, so I snap photos at the extreme range of brightness of the
lamp and then merge the pictures. I've
had good success for a long time with LED arrays; when I photographed Phil
Davis' coins these were all done with a 3x8 24 light LED array in an otherwise dark room, and many of the coins look lovely, although that's more likely caused by the
quality of Phil's selection than the
quality of my lighting:
http://www.flickr.com/photos/ahala_rome/sets/72157631141584632/detail/For when I don't use lighting, I've a north-facing balcony that gets no direct sunlight. I seek bright but cloudy days and I place the coins on a grey card on a table, and rotate the whole coin-camera setup a few times to vary the angle. It generally produces
very good results, but of course if I'm photographing all day, the light changes imperceptibly in intensity and direction. The rotating trick is key: put the coins and camera tripod on a rotatable surface e.g. a on a large book or tray with a glossy under-surface, shift it round a few degrees between consecutive shots, and then just select the best obv and rev when screening your pics.
However, some stubborn coins, especially camoflauge pattern bronzes, hard-green
patina bronzes, and reflective silver, and surface-corroded silver (i.e. as YOUR coin) almost never look
good. Sometimes one needs to catch these coins by surprise in a dark corner: the worst possible lighting conditions sometimes provide surprisingly
good results.
I guess my overall recommendation is to mess about a lot.
Success factors for me include: cloudy days, north-facing, LED light arrays, rotating between shots and selecting the best before editing, take camouflaged, corroded, dark or light coins by surprise (experiment!), and if it doesn't
work on one day, try another day with a different setting.
