# Start Calibration

Before capturing any images for observations, it is important to ensure that the majority of the markers can be detected properly by the system.

* If a marker is visible by the system cannot pick it up as a valid marker, there will be no overlay drawn ontop if it. From the capture window, you would just see the marker itself.
* When a valid marker is picked up by the system, an overlay would be drawn over the marker showing the ID of the marker with a colored background.
* When a marker is picked up by the system but it does not match the ones that should be in the associated calibration screen, an overlay would be drawn over the marker but with a greyed out background.

{% hint style="info" %}
Adjust the iris, gain, brightness of the display, and general lighting give the system a better chance at picking up the markers from the camera feed
{% endhint %}

{% hint style="warning" %}
Bring the iris/exposure to the highest possible F-Stop number (iris closed as possible) to have a high range of focus within the optical system.
{% endhint %}

{% hint style="info" %}
The back focus of the camera (if applicable) should also be adjusted and not change anymore once the calibration process has started
{% endhint %}

![](/files/FHBZMm6Y6YWOtKo968LQ)

Multiple images would need to be captured for the same Zoom and Focus step. Therefore, before you are ready to move to the next zoom/focus step, it is important that the zoom / focus values stay the same during the entire period.

To capture an image click on the icon: ![](https://manula.r.sizr.io/large/user/17749/img/camera-calibration-wizard-capture-frame.png)

{% hint style="info" %}
Press “F9” on your Keyboard to captures frames.
{% endhint %}

{% hint style="warning" %}
It´s very important that the camera and image for each single capture doesn’t move any more, to make sure that the captured image and the incoming tracking data really belong together.
{% endhint %}

Once an image has been captured, it would appear on the left hand side of the Calibration Wizard window.\
Repeat the capturing process until the entire image sensor of the camera has been covered.

{% hint style="info" %}
Try to get the calibration markers to be as close to the edges and corners of the image sensor of the camera as possible.
{% endhint %}

Move the camera to multiple locations within the tracking space to capture different locations as well as different rotations from the system.

{% hint style="warning" %}
It is important to go to the edge of your tracking space as much as possible while maintaining good tracking data.\
It is also important to change the pan and tilt as much as possible when taking these captures.
{% endhint %}

{% hint style="warning" %}
If possible, try to capture some images at a slight angle on all axis and not have the camera always looking at the calibration screen straight on.
{% endhint %}

![](/files/BLeikblcrt6hlg6INEhs)


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