New from Hikvision is Darkfighter PTZ, which combines a large CMOS sensor, strong WDR, a quality 23x zoom lens and 200m IR range to offer a solution of serious power.
WE’VE talked about Hikvision’s Darkfighter PTZ in SEN before but I’ve never seen it in action, so it’s off to the Hikvision head office in Sydney to check out this low light PTZ. It’s a handsome unit, robustly built and nicely balanced in appearance.
According to Hikvision, the DS-2DF8223I-A(AEL) Darkfighter PTZ is the world’s first 1080P Full HD ultra low illumination network PTZ that delivers full colour images in conditions the company says would defeat conventional monochrome IP cameras and competing low-light cameras. This is a big claim but looking at the images, I think it’s justifiable. You’d need to look at a number of top cameras side by side to be sure, but the Darkfighter PTZ is right up there at the top.
In terms of general specifications, DarkFighter PTZ has a 2MP, 1.9-inch high definition progressive scan CMOS image sensor. There’s 120 dB WDR (Wide Dynamic Range) and Hikvision’s 3D DNR (Digital Noise Reduction) technology, along with a 23x optical zoom. MPEG4, MJPEG and H.264 video compression formats are supported and the camera features multiple H.264 compression profiles, allowing users to optimize bandwidth and storage without compromising image quality. There’s also support for ONVIF, PSIA, and CGI standards allowing integration with other video surveillance equipment and systems.
Darkfighter PTZ employs the company’s ultra-low-light MP lens that’s designed specifically to capture sharp color and monochrome images in extreme, low-light conditions. Exactly what this means from a technical perspective is a bit uncertain. My sense is that Hikvision’s wholly-owned lens manufacturer is using superior lens material as well as coatings that are optimised for low light, and possibly a simpler internal design to reduce attenuation of light passing through the lens to the sensor. The wide F1.2 aperture on a lens with a focal range of 6-136mm is going to be contributing to low light performance, too.
Importantly, a lens that works well in low light is not necessarily a great lens in backlight or in daylight but the Darkfighter PTZ, like its full body sibling, handles daytime as well as any other 1080p camera. Something else Hikvision claims is that the new camera allowed license plates to be read at distances of hundreds of metres and yes, I can confirm this is true. I saw the unit resolving license plates effortlessly at 200m and apparently the Hikvision Australia team expects performance to be at least 300m, which is really something.
The company talks about getting colour(!) images down to 0.0005 lux, which is way less than the 0.002 lux of starlight. I didn’t see this sort of see-in-the-dark low light performance in our test though I can confirm the full body Darkfighter is very strong down to 5 lux in street surveillance applications, giving face recognition to about 5m at 7 lux. And with 200m IR capability, Darkfighter PTZ brings some big guns to the party.
Important for a camera with designs on dominating external applications, Hikvision’s DarkFighter PTZ is protected by an IP66 rating against rain and dust, as well as being rated to IK10 against vandalism. This latter is rather unusual in top-line PTZ of this size. Often the thinking seems to be that these bigger PTZs will be pole or wall mounted well out of harm’s way and there’s truth in this. But the fact Hikvision went ahead and fussed around with IK10 reflects well on the engineering team.
Tony Lagan, Hikvision Australia
According to Tony Lagan of Hikvision Australia, performance of the Darkfighter PTZ is excellent and the new camera has blown away audiences at recent demonstrations in Queensland and New South Wales.
“The Darkfighter PTZ has the full range of smart features – the IVA, intrusion detection, face recognition and smart tracking,” Lagan says. “There’s also line crossing detection and audio exception, as well as an IR distance of up to 200 metres, defog ability and electronic image stabilisation. It’s a very heavily featured product.
“The sensor is bigger than half an inch, so it’s a huge sensor and I think that’s what gives this camera its low light ability,” Lagan explains. “This large imager captures much more available light and is the secret to this cameras awesome performance.”
We are viewing Darkfighter PTZ images via a web browser, which is simple and capable, with a functional timeline. Performance of day and night images is very good. The lack of noise is a key thing for me. Noise is conspicuously absent from these images and there are no noise reduction artefacts I can see – none of that sort of blockiness. I am not getting a sense of motion blur from the images, either. It’s a tight performance.
There’s some colour shift towards yellow under streetlights but that’s quite normal – I can’t see any evidence of colour shift in night time scenes illuminated with fluoro and mercury halide. In fact, the scenes of the service station at night are better than they are in the day.
Hikvision Darkfighter PTZ at 12.15am – the intersection is 150m from the lens
We start by looking at Darkfighter PTZ recordings from late at night in a range of views. And yes, this camera is very impressive – it does well, it’s not showing obvious signs of noise despite the stress it’s under. We look at an intersection that’s about 150m away. There are streetlights around but they are low pressure sodium which is not much good for supporting colour cameras.
I’ve measured low light under street lights at sub 20 lux and adjacent to street lights at sub 10 lux so these scenes are not very well lit – some are 15 lux and some are probably down to 10 or even a little less. Darkfighter exaggerates available light so much it’s hard to get a sense of how dark the scenes actually are when viewing the monitor, which mirrors my experience when testing the full body Darkfighter last year. All you can do is get the light meter out and go walking.
Carpark scene at 12.20am – it’s not just the low light performance but the detail throughout a considerable depth of field that impresses
What’s also noticeable as Lagan changes gears on the browser is just how strong the camera is during the day. There are some scenes that are quite amazing – even under streetlight you’d need to have a strong sense of colour shift – a little yellow – to pick that a scene is under sodium vapour not late afternoon sun.
“The other thing to note is that in all of these scenes is that at no time – even 2am in the morning – has the camera not gone out of colour mode,” Lagan says. “But if it does get so dark the camera goes to black and white, there’s the 200m IR range to turn to so it’s a very capable unit. Not many PTZs are capable of supporting such an extensive zoom range with IR.
“So it actually has IR LEDs integrated into it – I can see them,” I say.
“Yes, it does have IR – it’s located behind the 2 panels on the face of the camera so you can’t see them,” Lagan says, pointing them out.
“What’s interesting is that PTZs are starting to become more popular and Darkfighter is right up there with the best. It’s a superb camera solution. We’ve applied this camera in Tauranga in New Zealand and the security manager there is absolutely delighted by the performance.”
Service station at 12.20am – nice colour and great detail – look at the reflections in the silver taxi. And again, the depth of field through this scene is exceptional.
According to Hikvision Oceania sales director, Michael Bates, this new PTZ camera is better than the full body Darkfighter for picture quality. This is a big call – zoom lenses with serious ranges seldom offer images that are better than smaller manual zooms – there’s too much light loss as the aperture closing during zoom, or considerable distortion at widest angles.
“The full body Darkfighter is an impressive camera but I think in terms of the combination of capabilities, the Darkfighter PTZ is a superior camera,” Bates says. “I think the image it provides is better, the lens is excellent.”
Lagan agrees.
“It’s an excellent camera that takes the Darkfighter capability to another level. There’s a big 23x zoom on this camera and you are going to get a lot of detail,” he says. “We are easily reading number plates at 200m and we think it’s capable of reading number plates at 300m. It’s extremely good against backlight – the image sensor, the lens quality, it’s just excellent.”
Great performance in daylight, too.
When we view images against strong backlight and sidelight during the day, there’s no sign of blooming at all, there’s no sign of flaring from the lens and zooming in during the night, the lens retains its strong low light performance. Because most the images we take have reasonable zoom applied, I’m not seeing any distortions of lines or vignetting with the big lens zoomed right in. This is another strong release from Hikvision.♦
By John Adams
