The viewing angle provided by the main camera of the DVR. As a rule, it is indicated along the diagonal of the frame, less often - horizontally, because of this, models with the same numbers in the characteristics may differ somewhat in the actual field of view. So if you have doubts about this, when choosing, it does not hurt to find and watch video samples from different models.
Other things being equal, a wider viewing angle allows you to cover more space, but individual details in the frame are smaller. In addition, wide-angle lenses give geometric distortions of the image (however, DEWARP can be provided to eliminate them, see "Functions"). As for specific figures, viewing angles
up to 120° inclusive are considered relatively small for modern registrars, values of
121 - 140 ° can be called average,
141 - 160 ° are above average, and the most wide-angle models are able to cover a space
of more than 160 °.
The largest size of the memory card allowed for the device. This limitation is primarily due to the fact that more powerful hardware is required to work with larger volumes. In addition, there are nuances associated with individual subspecies of cards. Anyway, this value cannot be exceeded: with a high probability, the registrar will either work incorrectly, or will not be able to work at all, or even completely fail.
Most modern registrars support cards
up to 32 GB or
64 GB, but there are models that are compatible with more capacious cards —
128 GB or even
256 GB.
