Scanning targets

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In order to scan a target you simply need to take a photo of each target and visually inspect the scan correctness. Even though TargetScan will try its best to process every target there is a lot you can do to improve the accuracy and consistency of the scan.

Choosing Quality Cards

Always prefer quality targets such as: Krüger, Edelmann. There are many reasons to do so:

  • Pattern Design - the pattern is expected to be exactly as stipulated in the corresponding Rule Book, if the targets has the 'Approved by ISSF' mark or 'Official Competition' NRA seal you can be sure that the pattern is correct
  • Paper Colour - the pattern recognition has been fine tuned to beige paper, also holes must have different colour than the paper which is easier to achieve on the beige card
  • Clean Holes - quality targets are made of special heavy pulp paper in which pellet/bullet cuts a clean hole easy to score
  • No reflections - the matte black paint has no reflections

Choosing the background

One of the key assumptions made in the automatic hole detection is that holes are lighter than the paper. You need to take a photo of the target making sure that on the photo holes are white or light blue. You can use for example:

  • iPad screen – iPad is perfect for scanning small targets, just open TargetScan on iPad and select the 'Lighttable' tab and place the card on the screen. When you take a photo it should be perfect.
  • Laptop screen – open /scan-backround page on your laptop and rest the card against the screen, make sure the screen is slightly dimmed
  • White sheet of paper - in good light conditions, especially when all shots are within the black aiming mark it is usually sufficient to just put a white or light blue sheet of paper under the card.
  • Wall or Window - you can also hold a big card against a window or well lit wall.

Taking the photo

Taking the photo make sure that:

  • Camera lens is clean – use a clean, soft cloth to clean the lens from dust, grease, and fingerprints
  • Entire Aiming Mark is captured - compose the photo in a way that the black Aiming mark of the pattern occupies 20÷100% of the photo
  • Ring lines are visible – TargetScan must detects inner ring lines in order to calibrate the pattern
  • Avoid perspective - if possible take the photo from the right angle, TargetScan will try to straight the photo if taken from an angle, but it is always best to take the photo from 90° (+/- 15°)
  • Hold Camera Still – if the photo is blurry you will not get accurate result

Editing the scan

TargetScan should recognise the pattern and localise holes automatically, but you can always edit shot location using 'Eagle Eye' on the scan preview.

Keep in mind that your smartphone has not been designed to be a scoring machine. In order to get accurate and consistent results you need to learn a little how to use it for scoring your targets.