The specifications provide the captured area at nearest and furthest distances:
However, both sets of values do not correspond to the same view angle (30 × 24.5° and 37 × 30°, respectively).
I wonder if the view angles (H × V) really differ depending on the distance, or if there is just a mistake in one of these numbers.
I saw a number of times on the forum that, for MINI scanner (not Mini2), the best accuracy is obtained at minimum working distance (10cm for Mini), for instance:
Conversely, with Mini2 in RevoScan, the “Excellent” distance range is not the minimum working distance (12cm for Mini2), but a larger distance (roughly 17 to 20cm).
Both questions thus turn into one: to get the best accuracy with Mini2, what is the optimal working distance, and what is the scanned area at this distance? (if the view angle is constant, it is easy to calculate, obviously).
All 3D structured scanners working the best at the minimal distance in this case Excellent .
I would not recommend to dig outdated old thread info as it constantly changes as the software improves .
So for best accuracy use the excellent distance or very slightly below it depends of the scanned objects because we don’t scan a sheet of paper flat on the surface so the distance from the bottom may be different than the of the top of the scanned object , as long you keep it at the proper excellent-good distance you get best results regarding accuracy .
Angles playing big role as well , again depending of the geometry and position of the object and it’s features and undercuts .
The frame size is the projected frame size of the projector at the specific distance at angle of 90 degree
Of course it will change at the angle but that really don’t matter .
It is like you buying a movie projector that tells you the maximum best viewing resolution is at 100"
The best scanning angle is 45 degrees assuming the direct top is 90 degrees
Because it can capture better the geometry and undercuts at that angle .
With Mini2, the “Excellent” distance range is 170 to 200mm, while the minimal distance is 120mm. Scanning distances between 120 and 170mm lie in the “Too Near” windows in RevoScan.
Ok, thanks for the tip.
I understand. So, to go back to my first question:
I guess that there is a mistake in the capture area values, right?
You can place the scanner at the 90 degrees direct project it to a white paper and measure the frame size at various distances , but do that really matters ? Not really , the important thing here is the amount of points a frame can capture per frame no matter the distance. However how higher the distance from excellent, how far apart the points will be .
I can confirm that not every device scan excellent at the same distance . The same is with camera lenses that each have their own sweet spot .
I recommend you use a very fine small object and capture it at a specific distances and compare the point distances then you know exactly the sweet spot of your device that deliver the best results . It can be a very minimal difference but the results can be huge especially scanning a very fine objects .