What are the key considerations when you’re setting up cameras for very long range work – what would you recommend? Our requirements are for face and plate identification during daylight hours and situational awareness at night.
A: The key consideration when using CCTV cameras over longer ranges is a stable base – any vibration at all is going to guarantee you won’t get the plates and faces you need, regardless of lighting conditions. We’d recommend concrete wall or roof mounting over pole mounting. Keep the brackets and other mounts as short as possible to ensure the least windage.
And on that subject, try to install the camera somewhere it’s protected from the strongest local prevailing winds. Very strong winds will cause camera shake, no matter how robust your base but bear in mind that such conditions will be abnormal. In windy conditions you’ll be grateful if your camera of choice has electronic image stabilisation. Something to think about if vibration proves to be an issue is vibration resistant mounts.
Other considerations of long range CCTV work will include the fact that longer lenses have smaller apertures – you can partly offset the impact of smaller aperture lenses with larger camera sensors to maximise the available light. You’ll also need to take into account the need to peer through atmospheric dust, fog or smoke. Selecting the right camera will be tricky. Instinct suggests you should probably go for a quality PTZ unit – the best PTZ units currently available are probably those from Bosch and Hikvision – Dahua also makes an excellent 48x PTZ that in a number of tests we’ve conducted has been seriously impressive, but it is a big unit. The most PTZ for the money would have to be the Hik Darkfighter X 4MP.
A more compact alternative would be a very long range bullet camera – we have not tested this but the 40x Fujifilm SX800 would have to be a serious contender. It has EIS, superfast autofocus and fog reduction technology, among other things. Another interesting option would be the AXIS Q6215-LE, which is a mil-spec 30x PTZ with 400 metres of IR range. Alternatively, you could put together a full body camera, lens and housing relatively affordably.
Lensing will be the biggest challenge. The best affordable long-ish range lens of our acquaintance is the Fujinon 15-50mm, which offers excellent performance on full body cameras – it’s a manual lens, however. For serious applications, we think Fujifilm is still the long range CCTV lens of choice. The XA4x7.5DA-DS1 is excellent but something to take into account is the very small F16 aperture at the long end, which will impact on night work.
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