Creation of milling data in GridPhoto.
GridPhoto is a convenient
solution for 2D photo engraving. Grey scale images are converted from
programs using a few Mouse
clicks into high quality milling data for almost all 3 or 4 axis
machine tools. In GridPhoto,
grey scale images are
processed and converted into dotted or linear milling data. The photos
should be available as grey scale images with 256 colours (exception
.JPG). The imported images can be edited, scaled, filtered, mirrored
and very rapidly converted into milling data.
With
milling there results a gridded image which resembles a photo, for
example in a daily newspaper The light/dark variations (grey scales) in
the photo are created through dots or lines with appropriate intensity
or density.
Using
Milling data graphics you can monitor the
calculated milling data and, as required, repeat the calculation with
modified settings as often as you wish.
GridPhoto has available various
grid, dither and hatching
processes for the creation of optimum milling data. In the grid process grey scales
are created through dots with varying diameter and the same separations
(3D milling data). The dither process creates
grey scales through dots with the same diameter and variable
separations (2Dmilling data). With the
hatching process the grey scales are represented
through 2D hatching lines in adjustable directions and separations.
Help
on the functions can be obtained with the activated navigator using <F9>,
in the menu also using [?] and clicking-on the
function.
Import photo.
|
Import
a grey scale image and adjust dimensions (measurements). The program
imports Bitmap files (256 Grey scales, 8Bitgrey scales, 1Byte/Pixel) in
the following formats:
BMP
|
Windows Bitmap
with 256 gray shades.
|
GIF
|
CompuServ Bitmap
with 256 gray shades. The GIF -format
contains no information on size or resolution.
The image dimensions must be adjusted
manually after import.
|
PCX
|
Paintbrush Bitmap
with
256 gray shades.
|
JPG, JPEG
|
JPEG Bitmap
with 256 gray shades, 8Bit colours and 24Bit
colours. JPG images with 24Bit colours are converted into a
gray shade image on import.
|
TIF, TIFF |
The
TIFF - import is qualified for 8bit (1 byte/pixel) and
16bit (2byte/pixel) unpacked grayscale pictures. With 16bit TIF,
reliefs with higher resolution can be saved or opened. Optional is a
fee required TIF - import/export extension obtainable for more picture formats and packed formats. |
Before
calculation of the milling path a photo should be processed into a
photostyler (e.g. Corel PHOTO-PAINT) and saved as grey scale image
(8Bit/Pixel - not in colour, exception .JPG). Images in the .JPG -
format can also be saved as colour images (24Bit). On import these are
converted into grey scale images.
Gridded
photos (e.g. from periodicals) have a very rough surface and should as
far as possible be avoided or reworked in a suitable photostyler.
Gridded images can also be improved using approximate fine/strong.
Height
- width ratio (Input in mm):
Proportional
:
|
YES:
|
All
axes modified proportionally the same.
|
No:
|
The
axes are input individually.
|
|
Dimension X/Y/Z [mm] |
Input
of the measurements in mm. |
Modify frame.
|
Edit
the relief limits (clip or expand relief).
Extract
XY: |
Take
over the area to be framed by a rectangle. |
Add
border: |
Create
a border around the relief.
Border width [mm]: |
Input of the additional border
around the relief. |
Same level [Y/N]: |
YES: |
The
relief is continued outwards around the border using the outermost
level. The subsequent border level input is inactive. |
No: |
The
relief is continued outwards using the value given in 'Border level'. |
|
Border level [mm]: |
Z value for the border around
the relief. This value is only effective with the setting 'Same level =
YES'. Only numbers between minimum and maximum relief Z values can be
entered. Default is the lowest relief point. |
|
Limit
top / bottom: |
Limits
the relief in Z (cut off relief top/bottom).
For Z value input first select a suitable (Z) point using the cursor in
relief. The Z level can be corrected to the correct value in the
subsequent input. Only numbers between minimum and maximum relief Z
values can be entered. Following confirmation the relief is
correspondingly limited. |
Scaling.
|
Adjust
a relief in size and resolution.

Scaling
%: |
Adjust
measurements in X/Y/Z (input in %). With Proportional = YES
all axes are the same, with No the axes are entered
individually. |
Dimensions XYZ: |
Height-Width
ratio (input in mm). With Proportional = YES all
axes are the same, with No the axes are entered
individually. |
Reduction
%: |
Enlarge
image in X/Y remove dots and with this reduce resolution and amount of
data. |
Levels: |
Grey
tone grading, coarsen image in Z. |
Double
resolution: |
Double
resolution of the overall image in X/Y. The position and enlargement
remain unchanged. |
Filter.
|
Revise/smooth
the photo. Suitable filters are, for example, approximate.

Error
pixels: |
Regional
filter. The dot, which deviates from all its neighbouring values by
more than the specified value, is approximated (smoothed). |
Outliers: |
Regional Filter. Delete large deviations to the neighbouring dots. |
Approximate/ approximate heavily: |
The
relief is smoothed. The approximating can, as required, be repeated
several times. |
Smooth: |
The
relief resolution is doubled and the image is, at the same time,
lightly smoothed. This filter gives significantly higher amounts of
data and should therefore be used only for coarse images. Images with
too high a resolution can be reduced again using 'scale . reduce (e.g.:
[%] = 50)' |
Radius
filter: |
Smooth
the relief, all edges are rounded off. |
Correction filter 1: |
Smooth
the relief, all edges are rounded off on one side. |
Correction filter 2: |
Fill
holes (e.g. after STL import). |
Mirror + rotate.
|
In
the case that it has still not taken place the image can be rotated or
mirrored in all axes. Mirror complete image in X, Y, Z and rotate by
+/-90°.

Mirror
X/Y/Z: |
Mirror
image in X, Y or Z. |
Countershape XZ: |
Simultaneous
mirroring for a countershape in X and Z direction. |
Rotate
+90°/-90°: |
Rotate
image by +90° (counter-clockwise) or -90° (clockwise). |
Line gridding. |
 |
 |
Using
line gridding grey scale images are
milled using a conical tool in 3D lines. The tool, depending on image
brightness sinks to different depths in the material and thus creates
the photo in the workpiece. Light areas of the image result in small
milling depths and, through the tool cone, small line widths. Dark
areas of the image, on the other hand, result in large milling depths
and wide lines.
With import of the photo the image is converted into a relief. The
measurements X/Y are the dimensions of the photo (reliefs). These ca be
adjusted using 'scaling'. The milling depth is determined by the relief
depth (input/modification, for example using scaling . dimension Z).
For the engraving of photos no large milling depths are necessary,
usually a few 0.1 mm suffice. The normal procedure is the engraving of
the image and subsequent covering (filling) of the cutter track using
colour. With the employment of multi-layer material the thickness of
the upper milling layer must be noted (set the safety height (Off)
higher and incise slightly deeper).
Display in upper window.
Measurement X/Y [mm]: |
Measurements of
the image and the engraved workpiece. |
Max.
milling depth Z [mm]: |
Indication of the
tool insertion depth in the material (relief depth). |
Milling
path separation: |
The milling path
separation (separation of the milling lines) is tool radius multiplied
by the line separation (/100%) with max. depth. The milling path
separation is heavily dependent on the tool angle TAn) and the relief
depth. Smaller tool angles or smaller milling depths result in more
milling data. The more lines which are milled the better effect the
image has. But with this the milling time increases. |
Line
number: |
Number of
determined milling lines. |
No. of
layers: |
Calculated number
of layers. If the 'layer depth' is selected >= 'Max. Milling
depth Z', then there is only one milling layer. |
Inputs.
Tool
#: |
Selection
of a suitable milling tool.
For milling, conical tools (with cone angle (CAn) >0°,
e.g. 20..30°)are always to be employed. The cutter tip should
be selected as small as possible (CuT <0.1 mm). For small cutter
tips always pay attention to sufficient rpm. |
Line
separation [10..500%]: |
The
line separation is related to the tool radius with max. milling depth
(100%). The milling path separation is determined by the line
separation. A larger line separation results in a larger milling line
separation and an image with a lighter effect. Recommended settings for
photo engraving are 100% .. 300%.
Reliefs (e.g. Lithophane for transmitted light) can be milled using the
program. For this a tool with larger tip radius or spherical radius and
smaller line separation (ca. 10..50%) is to be selected. With line
gridding only a tool offset of the cutter tip is calculated. We
therefore recommend the relief module or the program eMillRelief for
correct relief production. |
Angle
[-90..+90°]: |
Setting
of the angle of the milling lines. 0° produces horizontal lines. |
Procedures: |
Milling method selection:
 |
Hatching:
Simple lines without
turnaround. |
|
Cross hatching:
Simple lines without turnaround +
90° rotated crossings. |
 |
Hatching meander:
Lines in zigzag order. |
 |
Cross hatching meander:
Lines in zigzag order + 90°
rotated crossings. |
 |
Rectangle:
Rectangles concentrically ordered. |
 |
Circle:
Circles concentrically ordered. |
 |
Spiral:
Elliptical spiral. |
|
Radial lines:
Simple radial lines without turnaround. |
 |
Radial lines meander:
Radial lines in zigzag order. |
 |
Spiral > rectangle:
Elliptical spiral go over to rectangle
form. |
|
Layer
depth [mm]: |
Dependent
on the Max. Milling Depth Z the image can be milled
in one or more layers. If the layer depth is
exceeded, the program creates several milling layers. |
Contrast
[-0.5..+0.5]: |
With values >0 the image is higher-contrast (light and dark grey
scales are reinforced). With values <0 are milled with less
contrast. |
Inverse
[Y/N]: |
YES:
The brightness levels are inverted. Light areas are milled dark, dark
areas are milled light. |
Lines 100% |
Cross-hatching 150% |
Gridding.
|
Using gridding the grey scales in the image are
created by dots of various diameter and the same separations. The
variable dot diameters are created using a conical tool, which is sunk
(inserted) appropriately deep into the material. Small dot diameters
are achieved through small insertion, large dot diameters through
strong insertion (3D milling data). Conical tools and a 3D machine tool
are demanded for the grid process.
Display
in upper window.
Dimensions
X/Y [mm]:
|
Dimensions
of the image and of the workpiece.
|
Max.
milling depth Z [mm]:
|
Indication
of the greatest milling depth (for black dot) in the material. The max.
milling depth results from the dot separation and the tool angle.
|
Number
of dots X/Y/total number of dots:
|
Possible
number of dots if all dots in the lines are milled. At 'white' points
in the image no dots are milled. Please not the indication of the
number of dots during the input. The milling time (ca. 1-4 dots/sec)
can be estimated easily using the number of dots.
|
Inputs.
Tool
tip radius [mm]:
|
Smaller
dot separations and a greater total number of dots can be achieved
using a small tip radius. The tip radius should be selected as small as
possible (finest grid dot).
|
Tool
angle[°]:
|
Conical
tools are required for gridding. Convenient tool
angles lie at 40..49°. Smaller tool angles increase the milling
depth.
|
Safety height (SH) [mm]:
|
Safety
clearance of the cutter tip to the surface of the material for
withdrawn movements. The smaller the safety height is chosen the more
dots can be milled at the same time.
|
Processes:
|
Milling processes for the image.
Vertical:
|
Each dot is milled vertically from the safety
height into the material (long movements).
|
Inclined from Mat.:
|
The
dots are milled into the material inclined along the tool angle. Up to
the next dot an inclined movement takes place up to the material
surface (short 3D movements).
|
Lines:
|
The
individual milling depths are connected together by lines so that
milled lines of different depth and thus different stroke widths result
(short 3D movements).
|
Inclined
from SH:
|
The
dots are milled inclined along the tool angle into the material. Up to
the next dot an inclined movement up to the safety height takes place
(long 3D movements).
|
|
Dot
separation [mm]:
|
Separation of the grid points.
The dot separation must be selected at least 4 x
Tool tip radius, otherwise no contrast is possible within the
image. The greater the ratio Dot separation/
Tool
tip radius is
selected, the more contrast is possible in the milled image.
|
Density
value:
|
A density value < 0 results in a lighter
image after the engraving.
|
Example for dot grid. |
Example for line grid. |
Dithering.
|
New
process from Ver. 7.022
The
dither process creates the grey scales in the
image through dots with the same diameter but variable separations (2D
milling data). Cylindrical or conical tools can be employed for the dither
process. A 2D (2.5D) machine tool suffices for the milling processing.
The dither milling data can, in a wide range, be matched
to the job definition. An image milled using the dither process is
effective from a minimum viewing separation. A sufficiently large image
should also be milled. The program offers 3 milling processes:
Dithering 9p, Dithering 16p and Dithering 25p. Dithering 25p should be used for large area images only,
Dithering
9p is suitable
for rather smaller images.
To test a suitable milling image select Settings (see below)
and Start. You can repeat the calculation using
changed settings as often as you like. For a rapid graphic set the Milling data aspect
to Milling point
Through the relatively large-area dither dots the dimensions of the
graphic cannot be adhered to exactly. The deviation of the milled image
is visible in the graphic.
Display
in the upper window.
Dimensions
X/Y [mm]:
|
Dimensions
of the image and of the workpiece.
|
Max.
milling depth Z [mm]:
|
Indication
of the tool inserted (sunk) depth in the material.
|
Number
of columns X / lines Y:
|
Possible
number of the dither dots if all dots are milled in the lines. No dots
are milled at 'white' points in the image, a dither dot consists,
depending on the process, of several (up to 9, 16, 25) 2D
dots.
|
Inputs.
Tool tip radius [mm]:
|
Smaller
dot separations and a greater total dot number are achieved using a
small tip radius. The tip radius should be selected as small as
possible for a high image resolution.
|
Tool angle[°]:
|
Cylindrical
[0°] and conical tools [>0°] are employed for
dithering. Convenient tool angle lies at 10..20°.
|
Safety
height (SH) [mm]:
|
Safety height of the cutter tip to the material surface for withdrawn
movements. The smaller the safety height is selected the shorter is
insertion (sink) movement and the more dots can be milled at the same
time.
|
Inserted (sunk) depth [mm]:
|
Milling
depth of the tool measured from the tool tip to the surface of the
material.
|
Density
[-0.5..+0.5]:
|
Change
the milling dot density. With values <0 the dots are more dense,
with values >0 are wider displaced.
|
Spread
[0..1]:
|
Spread
of the individual dots. With the setting 0 the dots are placed at
regular intervals (best quality). Using larger settings the dots are
dispersed. A spread results in a small reduction in quality. The image
appears somewhat washed out/blurred.
|
Brightness [-0.5..+0.5]:
|
With
values >0 the image is milled lighter, with values <0
milled darker.
|
Contrast [-0.5..+0.5]:
|
With >0 the image is milled with higher
contrast, with values <0 with less contrast.
|
Inverse
[Y/N]:
|
YES |
The brightness
level is inverted. |
No |
Brightness
distribution as in the model. |
|
Processes:
|
Dither
milling processes for the image.
Dithering
9p:
|
For
rather smaller images with reduced grey scale intensity.
For 1 dither dot 0(white) .. 9(black) individual dots are milled (fine
resolution).
|
Dithering
16p:
|
For
medium-sized image sizes with sufficient grey scale intensity. For 1
dither dot 0(white) .. 16(black) individual dots are milled (medium
resolution).
|
Dithering
25p:
|
For
larger images with many grey scales. For 1 dither dot 0(white) ..
25(black) individual dots are milled (coarse resolution).
|
|

Comparison
of the dither processes. From left to right 9p, 16p and 25p. Above
spread 0, below spread 0,5.
 |
 |
Same
image as above but double dimensions and brightness + contrast
respectively 0.1. Setting s. image.
Milling data
view setting Relief view.
|
Hatching.
|
Convert
grey scale image into hatched image. For this the grey scale number is
reduced and the individual level replaced by hatching so that a gridded
image results. For an as high as possible contrast result a photo
should be processed in a photostyler beforehand. Here, disruptive
elements should be removed and a stronger contrast selected. For the
hatching a tool must be determined whose tip is to be selected as fine
as possible (Cutter tip [CuT] 0.05..0.1mm). The hatching separations
are determined automatically using the cutter tips, the grey level and
the following settings.
Hatching
levels [1..32]:
|
A
grey level image (256 levels) is reduced to 1..32 hatching
levels. Sensible are 4..32 hatching levels.
|
Density
[-20..100%]:
|
Change hatching density (line separation). The
effect corresponds with the contrast setting. Values < 0 reduce
the contrast, values > 0 raises the contrast.
|
Brightness
[-20..100%]:
|
Change
hatching separation for all hatching levels uniformly. The effect
corresponds with a brightness setting.
|
Hatching
contour separation [0..100%]:
|
Determines
the safety separation of the milling tracks in the milling direction to
the contour (track). With the selection Combine hatching lines = YES this value must be > 0 and lie at ca.
50% (>10% .. 70%).
|
Hatching
angle [-2,-1.0..180°]:
|
-2
|
The hatching angle is
automatically set for each layer with increasing value.
|
-1
|
The hatching angle is automatically set for
each layer with increasing value and alternatively displaced by
ca.90°.
|
0..180
|
The hatching angle is set for
all angles at the specified value.
|
|
hatching directions [1..6]:
|
1
|
Hatching lines in set direction only.
|
2
|
Hatching lines in set
direction, displaced + 90°.
|
3
|
Hatching lines in set direction displaced +
60° and 120°.
|
etc.
|
Join
hatching lines [Y/N]:
|
YES: The
hatching lines are joined together.
|
Add
hatching contours [Y/N]:
|
Yes: Save
the hatching limits to the created paths.
|
Tool
input for hatching.
For
the creation of milling data complete tool information is required. The
tool data are entered in the tool list. The tool list can be reached
with Tool Input.
Milling
data view |
 |
This
setting of the milling data view is employed if milling data has been
calculated using gridding, dithering or hatching. The black
indicated form of view is set. The forms of view in
blue
can be selected. |
Milling point: |
Drawing
of the milled image in plan view with filled cutter trace (cutter
simulation, rapid display). |
Relief
view: |
From
the milling paths a relief (3D form) is calculated and drawn in grey
scale image (slow display due to the high computing time). |
Render
view: |
A
rendered image is calculated from the milling paths and is displayed
(slow display due to high computing time). |
Relief
colour: |
Representation
of the relief and render view.
Standard: |
Standard grey
values. The background is white,
milling points are presented dark. |
Inverse: |
Inverse grey
values. The background is black,
milling points are presented light. |
|
Milling data graphics.
|

|
Drawing
of the milled image in plan view with filled cutter trace (cutter
simulation).
|
Milling data > Layer.
(Only for CAD/CAM complete system)
|
Take
over the milling data in a graphic layer.
Milling data export.
|
Following
calculation, the milling paths can be exported in various formats.
Navigator.
|

|
In
the Navigator the most important program functions are
summarised in the correct processing order. The Navigator leads you
through the processing. Processing takes place from top to bottom. You
can select the function marked in black. If a function is not to be
selected then, using next you switch to the next
operation. Using back you switch to the previous
function.
|
Open (Import photo):
|
Import
a grey scale image and adjust the dimensions (measurements).
|
Filter:
|
Rework/smooth (finish) the image. Suitable
filters are, for example, approximate.
|
Mirror+rotate:
|
In
the case that it has still not taken place, the image can be rotated or
mirrored in all axes.
|
Raster
photo:
|
Gridding.
|
With
Gridding
the
grey scales are created in the image through dots with different
diameters and the same separations.
|
Dithering.
|
The
Dither processes create the grey
scales in the image through dots with the same diameters and variable
separations (2D milling data).
|
Hatching.
|
Convert
grey scale image into hatched image. For this the grey scale number is
reduced and the individual levels is replaced by hatching so that a
gridded image results.
|
|
Milling data export:
|
Following
calculation the milling paths can be exported in various formats.
|
End Navigator:
|
Program
operation without Navigator. Now all menu functions are available. For
operation please follow the program help [?] or <F9> and
click-on the function.
|
|