Canon Camera Hackers Manual page 32

judging of the outcome if you plan to print in 6" x 4" format, for instance.
The 1/3-rule grids are mostly used for positioning the horizon in landscape
photography; dividing the image by a ratio of 2:1 or 1:2 is more pleasing
than placing the horizon in the center.
The CHDK greatly extends the range of available grids. You can even
define your own grids in the form of a simple text file. Each grid is imple-
mented as a .grd file in the folder CHDK/GRIDS/. If you want to roll your
own, you will find the necessary instructions in the file README.TXT in the
same folder. Predefined grids are:
f 3to2grid. Indicates the 3:2 crop ratio, e.g., for 6" x 4" prints.
3to8grid. Organizes the image horizontally and vertically into 3:2:3 di-
f
visions. This is very close to the Golden Ratio. It can be used to compose
an image in a visually pleasing way by aligning the prominent struc-
tures with the grid lines.
golden1. Indicates the "Golden Point". The most important subject in
f
the image should be placed where the two lines meet. Horizontal or
vertical reflections of this grid can be used, too, resulting in four "golden"
points.
golden2. Identical to golden1 but showing two "golden" points.
f
id. Based on the ISO/IEC 19794-5:2005 standard for administrative
f
identity photos (passports, identity cards, driving licenses, etc.). The
large red ellipse shows the maximum head size, the small green ellipse
the minimum head size. The gray area is where the eyes have to be.
rulecross (rulecr~1 on DryOS). A grid typically used in aerial photogra-
f
phy and micro/ macro photography.
rulers. Similar to rulecross, but without the crosshair pattern.
f
sports. A grid simulating a sports finder. The nested frames represent
f
the different cropping lines. The idea is that you shoot at the highest
resolution and later crop along the lines shown in the grid—resulting in
a telephoto shot with lower resolution. The main advantage over digital
zoom is that the display shows the events outside the cropping area,
too. This gives you time to prepare for the shot and enables you to catch
the event in time.
stolen. A grid for the paranoid. When activated, the grid darkens the
f
screen showing only the words "STOLEN CAMERA!" The idea is that a
person unaware of the CHDK will not be able to use the camera. A new
memory card, however, would cure it.
third_h. Organizes the image horizontally into equally sized divisions
f
(horizontal 1/3-rule).
third_v. Organizes the image vertically into equally sized divisions
f
(vertical 1/3-rule).
4.2 Customizing the user interface
Figure 4-12
The rulecross grid
Figure 4-13
The Grid Lines submenu. Normally, grid
files define the colors for lines and
background. However, by enabling
Override Grid Colors you can override
these colors with your own color
selections.
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