# SLR Cameras via USB connection

<img src="https://helpdesk.vioso.com/wp-content/uploads/2020/03/815iZYNaLNL._SL1500_-300x262.jpg" alt="" height="262" width="300">

Digital SLR cameras made by Nikon or Canon can be used for calibration, connected with a USB cable.

For this purpose, the camera has to operate in the *web-camera mode*.

While some cameras have this mode in their firmware, most cameras do not , so a different third-party software can be used for this conversion:

* <https://sparkosoft.com/how-to-use-dslr-as-webcam>\
  Commercial solution
* <http://www.instructables.com/id/Use-your-Canon-EOS-1000D-as-Webcam/>\
  Free of charge, but seems complicated and not capable of delivering the full resolution.

{% hint style="info" %}
**Please note:** Since there are so many types, brands, and models of cameras, as well as a lot of third-party software converters, we can’t test them all. As a result, we can not guarantee that your camera will work for the calibration process. Please perform some tests beforehand.
{% endhint %}


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