Why is it important to make the optical setup?
It is important to define the scanning area, the position and orientation of the cameras and their focus.
What is the work distance of a scan?
The work distance is defined based on the scanning area. In Table 1 of the manual: "relationship between scanning area and distance" are described the equivalences between distance and working area.
How can I chose the acquisition field for the object I have to scan?
Based on the object's dimension, the area of work goes from a minimum of 100x80mm to a maximum of 500x400mm. For instance [LINK ALLA MESH DI HULKHOGAN] has been scanned with a working area of 200x160mm and its dimensions are: length 210mm, height 310mm and 80mm of depth.
Can I use a preset work area (Table 1 of the manual)?
No, it's not possible. Chose a scanning area as close as possible to the desired one.
If the object is too big with respect to the maximum acquisition field?
Do partial scans dividing the object in various parts trying to acquire some "features" that the parts have in common to consequently align them, establishing as a limit a field 5 to10 times bigger than the maximum scanning field (5000mm).
What are the consequences of a poor/approximate optical set up?
The scanner's performance would not be optimal: the dimensions of the scanned object would not correspond to the original and the scans could have defects or rough areas.
What if the cameras are moved by mistake after the optical setup?
The optical setup will have to be carried out again.
When is it appropriate to calibrate (9 images) and when to re-calibrate (3images)?
The 9 images calibration should be carried out (apart from the first time the scanner is calibrated) all the times the optical setup of the scanner is changed. On the other hand, if this is kept fixed, the re-calibration must be carried out if the dimensions of the scanned object appear to be imprecise.
Can I also calibrate the scanner with a Master which is not the one provided with Scan in a Box?
No, it's not possible. Some characteristics of our system (such as the work areas, calibration master) have been studied specifically fir our product. Change these parameters could cause issues leading to a INCORRECT scan.
What are the consequences of an approximate calibration?
If the calibration is poor the dimensions of the object will appear distorted. This causes measuring issues concerning the object's dimensions and issues regarding the alignment of the scans.
During the calibration process, between one image and another I noticed a number of markers that were not acquired, what does that entail?
That would entail a NOT optimal calibration of the scanner, leading to errors in the accuracy of the model to acquire.
The Calibration Master's surface is ruined. What does this implicate?
In order to have a correct calibration the Calibration Master must be intact. If there're visible imperfections of the surface, there are bumb that are caused by the humidity or some markers are missing, the custumer will have a not optimal calibration.
On the other hand if the one or more central marker are missing the calibration will fail.
We strongly advice to use the master carefully and put it back on its bag. Do not place on it anything that can scratch its surface. The Calibration Master is absolutely not suited to be used as working plane.
The Calibration Master broke. Should I get rid of it or I can still use it?
The Calibration Master is essential for the correct scanner operation. If the plexiglass plane is completely broken the master can't calibrate the scanner and it must be replaced. If the master is broken in one or more angle, it can be used as long as the 3 central markers are intact. There is always the chance that the corner acquisition is falsified and it may generate errors. It's advised to replace the Calibration master in order to have better results .
I tried to scan an object. The result obtained is a range image with points badly organized in space so the 3d object looks like to the scanned model, but barely recognizable and deformed. What happened?
With this result it's likely that the cameras were reversed . It's advised to check on the cameras' stand if the CAM.01 and CAM.02 signs matches with the one on the aluminium bar. If it's not the case you must put the cameras in the right position and calibrate the scanner afterwards.
I'm about to use Scan in a Box again, after an inactivity period. Do I have to calibrate the scanner again before I scan?
It doesn't need to be re-calibrated if It was kept assembled with a per-configurated set-up.
You must calibrate the scanner if it was disassembled or in some way the camera's position or the optical set-up changed
If I move by mistake the scanner or I tilt it do I threaten what I've done so far?
The scanner can be moved without threatening the calibration procedure, in fact we suggest to take the most of the tripod's movement. Remember to keep the right distance between the object and the projector during the scan
I moved the cameras or changed the projector focus, should I re-calibrate the scanner?
If you close firmly and in the right position the cameras and projector you don't have to worry about it. Scan in a box's technology needs the scanner's re-calibration only if you change the field of view or if you un-assemble it.