1. Macro mode allows the camera to focus on objects closer to the lens...normally your camera won't focus on something until it's at least 2 feet away or more. Some will focus closer, some further. The issue with non-macro mode is that if you have to be 2 feet away, you end up zooming in to fill the screen with the coin (or cropping) and losing quality.
2. Macro mode also widens the aperture, so your depth of field is greatly reduced. This just means only objects a specific distance away will be in focus (see the flower pic taken on our vacation last year below, the petals are in focus but everything else is blurry).
3. If your coin is dark, place it on a dark cloth or a dark something that isn't shiny. The camera will take the white balance value automatically based on objects in the picture, so if it's on a light cloth your coin will be even darker in the photo. If you use a dark cloth, the coin will be brightened up! See photo #2...the brown in the picture is actually much darker, but because everything in front of the lens was dark, the camera compensated by lightening it up. If I had taken the photo on our light carpet, the details of the coin would have been lost completely.
Take pictures of light objects on a light colored cloth, opposite of dark object rules.
3. In macro mode, light is very important. make sure your light is behind you (ie: put the coin on the floor, centered under the light in the room). This will make sure your shutter speed is fast enough to take a photo that isn't blurred. Low light will cause the shutter speed to be slower so the camera can take in more light.
4. If the coin is silver or the object is shiny, take the photo from a little bit of an angle. When the flash goes off or the light behind you is shining on it directly, you'll get a huge white spot on the coin in the picture.
Any questions, I'm happy to help
