Before you start taking photos for the coin scanner app, you must create perfect conditions, stopping mistakes linked to bad light and background usage.
You should choose a background having one color, not showing any patterns, lines, or bright marks. This is necessary, preventing the program from confusing background parts with small coin details.
The background should be matte — shiny surfaces create bright spots that hide the small details of the coin, so it’s better to use thick matte paper, felt, or a piece of plain cloth.
Contrast: The background color must be very different from the coin’s color.
- For light-colored coins, start by using a black, dark blue, or dark green background.
- For dark-colored coins, continue by using a white or light grey background.
Lighting
Having the wrong light is the main reason why apps cannot recognize the coin well.
You must use spread out light, not direct light, because strong light from a lamp or flash makes hard shadows and bright spots, hiding the coin’s relief. Soft light shows all the coin’s details evenly, making the picture better.
It is better using two or three light sources, placing them at a 45-degree angle to the coin, and they must have the same strength and same color temperature.
You need to turn off the flash on your smartphone completely, knowing that the flash creates a very bright spot right in the center of the coin, making the main identification marks invisible.
If you use daylight, place the coin next to the window, but avoid direct sunlight by using thin white paper or cloth as a diffuser between the coin and the window.
Keeping the Device Still
The picture quality really depends on how still your phone is.
You should try using a small tripod or smartphone stand, this is necessary in order to prevent even a slight hand shake, which can make the image blurry.
If you don’t have a tripod, you should use the timer function in the Camera app, remembering that tapping on the screen may cause a slight movement, but the timer allows the phone to stop moving before shooting.
The Coin Shooting Process
With your workspace now ready, you can move to the actual photo-taking process.
Place the coin strictly flat on the chosen matte background, the coin needing to lay evenly without any tilt. Don’t touch the coin surface with your fingers, stopping yourself from leaving marks, and if you need to turn or adjust the coin, use soft round-tip tweezers.
Open the coin value checker, finding many of these apps have a built-in shooting tool like in the Coin ID Scanner, which automatically prepares the image for recognition.
Camera Position
This is the most important technical point, where your camera lens must be placed strictly straight to the coin surface, meaning a 90-degree angle.
If you take a picture of the coin from an angle, the coin’s shape in the picture will look wrong, causing the app to fail in measuring the diameter and comparing it with the database information.
Focus and Sharpness
Make sure the camera has focused exactly on the coin.
If the app allows this, set the focus yourself, pressing on the coin’s center on the screen.
The image must be as sharp as possible, because any blur, caused by bad focus or shaking, will lead to a recognition mistake.
The smallest relief details and letters must be clearly visible, even if they are worn down over time.
The coin must fill most of the picture frame, but without being cut off.
There must be a small area of the same background color around the coin, this area helping the app separate the coin from the rest of the space and process it correctly.
For the coin’s full recognition, you absolutely need two pictures:
- Obverse
- Reverse
Take pictures of each side separately, following all rules for light and straight placement.
Special Cases and Advanced Pictures
Some coins or apps need extra pictures for perfect identification or coin value check.
The edge is the side part of the coin. If your coin has writing, a pattern, or marks on the edge, you may need a separate picture of it, this picture also being important for exact identification.
- Stand the coin straight up, using a special stand or two small supports, and take a picture of the edge from the side, making the pattern or writing visible. The light must be direct but not too strong, stopping bright spots.
For Condition Check
If you want the app or an expert to check the coin’s condition, you may need a series of pictures with slightly different light.
Take a picture, directing the light at a very sharp angle to the coin’s surface. This light shows the smallest scratches, wear marks, and relief details, which might not be visible with normal soft light.
Checking and Fixing Mistakes
Before you upload the pictures to the app, you must check their quality.
Zoom in on the finished picture on your phone screen.
If the letters, numbers, or small details look blurred, washed out, or not clear, the picture is wrong, and you must quickly take the picture again, fixing the cause of the blur.
Look for any bright white spots on the coin, those spots completely hiding details.
If these spots are present, they are bright light spots, the reason being direct light hitting the coin.
Go back to point 1.2 and make the light softer.
The coin’s color in the picture must be as close as possible to its real color, Coin ID Scanner sometimes using color to find the metal.
If the picture has a strong blue, yellow, or green shade, the app might make a mistake finding the metal type.
Using the Data After Scanning
The Coin ID Scanner app compares the shape and design data of your picture with a very large database of correct pictures, looking for matches based on these points:
- Size and Thickness: If you give the sizes, the app uses them, and if not, it measures the size from the picture, using the known distance between pixels or an extra size scale, if you used one
- Placement of Parts: The program looks for matches in fonts, number of letters, shape of the state symbol, position of stars, and other parts
- Year and Mint: Based on the exact reading of small symbols and letters, the app finds the release year and, if needed, the mint mark
If the app gives several options, not choosing one, or if it makes a mistake, you can always make changes yourself. A good quality picture allows you to see all the small details yourself and enter them into the app.
After the coin is successfully recognized, the app usually puts it into your personal digital list, where its details, your photo, and maybe its estimated price are saved.
Important Note About Cleaning: Never clean coins before scanning, especially old or valuable ones. Cleaning can damage the patina, which will quickly lower the coin’s value. The app must scan the coin in its current, real condition. Any dirt that is easy to remove won’t stop recognition, but damaging the patina will affect the value check.