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OnTarget Feature List
Calculates: group center, maximum group spread (CTC), average distance
to center, group width and height, and group offset from point of aim.
Measurements are displayed in inches and minutes of angle (MOA).
All project information, including the target graphic, is saved in the
project file. Files can be shared between users without recalibration
or adjustment.
Pre-defined values for common target distances and bullet hole sizes along
with user defined custom values.
All settings carry over from one project to the next. No need to
re-enter setup information.
Integrated scanner support using Micrsoft's WIA (Windows Image Acquisition)
system.
Imports and saves popular graphic file types. (.jpg .bmp, .tif, .png)
User defined point-of-aim on target. Aim point is used to calculate
group offset.
User selectable group text displayed in Target View and in saved graphics.
User selectable graphical elements for maximum spread, group extents, and
average distance to center in Target View.
Zoom commands include: graphical zoom, zoom in, zoom out, fit window,
and zoom to selected group.
Graphical ruler for measuring distances in Target View. Correctly scaled
regardless of zoom level or graphic source.
User selectable line thickness and color for the graphical elements
of the group in the Target View.
Entry fields for project title, date, location, name, and project notes.
The average values for all groups in the project is calculated and
displayed in the Target Info tab.
Easy to use image size calibration tool.
Popup menu in Target View for frequently used commands.
Oversized toolbars for easier use.
Measuring Group Size
There are several methods for measuring and calculating
the size of a group of bullet holes in a target. These methods
vary depending on the tools and equipment available but the goal
is always the same; determine the
center points of two or more holes in a target. Once you
know the position of the center points the group information can be
calculated very easily.
Traditional Methods
The two most common methods of measuring bullet hole groups
involve the use of calipers. Both methods are used to calculate the
maximum spread, or center-to-center distance, of the group. Let's
take a quick look at each.
In the first method a standard set of calipers is used to measure the
extreme distance to the outside edges of the holes in the group.
Then several holes are measured and an average size calculated.
Finally the average hole size is subtracted from the overall measurement
resulting in the group center-to-center distance.
The second method of measurement uses a set of calipers modified
to hold a pair of clear circlular templates along with an eyepiece for
optical magnification. The operator looks through the eyepiece,
aligns the two circles with the extreme holes of the group, and reads
the center-to-center distance directly from the caliper.
Both of these methods produce very accurate results and with
practice can be done rather quickly. The first method is more
commonly used because it can be done with a standard set of calipers.
The second method is used to certify groups because if its greater
accuracy.
OnTarget Method
Now let's take a look at how OnTarget calculates group information.
OnTarget uses the center of the bullet holes to
calculate the group information. First an image of the target
is imported. The desired bullet hole size is set along with the
target distance, the point of aim, and the reference distance if
needed.
The user then zooms in on the bullet holes that will be
added to the group, selects the hole input
tool and clicks in the Target View. A circle
is displayed that moves with the mouse. This circle is
drawn at the defined bullet hole size. The user positions
the circle over each bullet hole in the group and clicks
the mouse button to anchor the hole. At high zoom levels
the position of the hole has a resolution of .001".As the
holes are entered the group information is automatically
calculated and displayed.
The use of the circle on the view of the target allows the
user to accurately position the center point of the hole. Even
if the bullet hole does not have a clean edge all the way around
the circle can be positioned accurately with just a few small
sections of the bullet hole edge showing.
OnTarget
Features