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Processing and analyzing magnetic copy stitching
z
Rotate the stitched copy to match the original, using manipulation functions: image
rotation and mirror imaging.
z
Evaluate the quality of stitching visually. If the quality is satisfactory, save the initial
file and start processing and analyzing. If the quality is unsatisfactory, repeat magnetic
copy stitching or make a new magnetic copy.
z
Process the stitched image using software functions. In general the following functions
give the most effective results: threshold processing with the possibility of brightness
levels band spreading, image differentiation and spatial filtering.
z
Analyze magnetic copy stitching:
{
Visually determine if there are any signs of number alterations. The main
signs of alterations examined are the following: traces of mechanical
processing taking the form of traces or nicks (Figure 4: 2nd, 4th and 6th digit
positions); original number fragments (Figure 4: 2nd and 6th digit positions);
non-ferromagnetic materials fragments (Figure 4: 4th digit position); welded
seams and borders of pressing in (Figure 4: 4th digit position).
{
Additional signs of number alterations examined are the following: deviation of
form and arrangement of digits in the number; different intensity (clearness)
of the number digits contour; non-uniformity or absence of the object surface
texture processing. It should be taken into account that the last two features
can result from a poor quality copying (magnetic tape does not fit closely to
the surface).
{
Compare the images of the digits with the specimen numbers of this model of
firearms or with digits repeated in the examined number.
{
Measure geometric dimensions of the images of the digits and analyze their
position. The software allows measuring linear and angular image dimensions.
z
Analyze examination results.
Documenting examination results
z
Save the initial file of magneto-optical visualization of the number platform. It is also
possible to save processed images.
z
The magnetic copy can be saved as material evidence.
z
Print the obtained images.
Magnetic Copying Accessories Set
2.2.2.1 Operating limitations
z
Only ferromagnetic materials (iron, steel, cast iron) can be examined. For nonferromagnetic
materials (aluminum) the corresponding eddy-current scanner must be used (supplied
optionally).
z
The thickness of examined lacquer-and-paint coating shall not exceed 0,5 mm.
The thickness of an examined rust or scale layer shall not exceed 0,3 mm.
z
Examined surface unevenness shall not exceed 0,5 mm at the basic width of 11 mm
when using the
CMS
flat concentrator.
z
Examined surface unevenness shall not exceed 1 mm at the basic width of 20 mm when
using the
CMS
rotary concentrator.
z
Protect the CMS concentrators from blows and falls to avoid damaging magnets and loss
of magnetic properties.
z
Damaged rubber protective sleeve gaskets of the
CMS
rotary concentrator should not
be used during device operation.
z
Do not use MT strips shorter than 150 mm (see paragraph 2.2.1.1).
2.2.2.2 Preparing the MCAS for operation
Set inspection:
z
Check availability and proper arrangement of the set components.
z
Make sure that there is MT and ethyl alcohol in reserve.
z
Check MT surface integrity and cleanliness (see “The Order of Refilling”).
z
Visually control the integrity of the rubber sleeve gasket of the CMS rotary concentrator.
If necessary, replace the worn out sleeve gasket with a new one (see paragraph 4.2).
2.2.2
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