CCTV

Clearfix
Thu
07
Dec
JohnA's picture

How Sharp are Wide Angle Camera Lenses?

Wide views give loads of detail at the cost of sharpness
Wide views give loads of detail at the cost of sharpness

HOW sharp are fixed wide angle camera lenses? We do often use angles of view of 90 degrees at F1.6 and we like them as they are set and forget, with no drift of moving parts as you might get with varifocal lenses. But we sometimes wonder if we are missing out on quality with a fixed lens and such a fast aperture. What does SEN think?

A: Typically, any lens is sharpest a couple of stops down from wide open – for an F1.6 lens that will be around F4. The correct apertures to shoot front to back of scenes are the narrowest aperture numbers – F8 at least and preferably F16 or narrower, diffraction (and light levels) permitting. 

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Tue
21
Nov
JohnA's picture

Camera Review: Mobotix M16 – First Impressions

Mobotix M16 - properly installed it will give nearly a decade of service
Mobotix M16 - properly installed it will give nearly a decade of service

MOBOTIX M16 is a modular, dual sensor surveillance camera system that offers installers and end users much more than meets the eye. It’s a PoE, 6MP day/night camera with an integrated housing, rated IP66 and IK10, supported by MxManagementCenter and MxAnalytics software and offering H.264 for the first time in a Mobotix camera. 

Holding the Mobotix M16 in the hand is instructive – it doesn’t feel like a modern surveillance camera. The M16 is compact but at just under 1.2kg it’s a hunk, with the camera system buttoned up inside a Polybutylene Terephthalate (PBT) housing reinforced with glass fibre to increase strength, stiffness, impact resistance and the ability to withstand heat, acids, oils and sunlight. Strength is a design characteristic – this camera has an MTBF of 80,000 hours – that’s around 9 years of constant operation.

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Fri
15
Sep
JohnA's picture

Samsung Wisenet XNO-8080R Bullet Camera Review

Samsung Wisenet XNO-8080R
Samsung Wisenet XNO-8080R

Samsung Wisenet XNO-8080R is a 5MP bullet camera with WiseStream II support, a speedy F1.2 motorised varifocal lens with a range of 3.7-9.4mm, 30ips of resolution, H.264 and H.265 compression, 50m IR range, IP67/IP66, NEMA 4X and IK10 ratings against weather and vandalism, and video analytics including loitering, sound classification, fog detection, digital auto tracking and tampering. 

SAMSUNG’S XNO-8080R 5MP bullet camera with WiseStream II support is a capable all-rounder, specifically designed and build for tough outdoor applications. Everything about the spec is hardy – holding this camera in the hand is a pleasure and I get no sense of shortcuts in construction. Fortunately for SEN, manufacturers tend to only send us their top-end gear to play with so it’s never hard to get excited about the high-quality cameras we test. Some are better than others and the 8080R is definitely in the better group. 

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Thu
07
Sep
JohnA's picture

Very Wide Angle Views: Hemispheric or Multi-Head CCTV Cameras?

Fisheye cameras offer hemispheric views
Fisheye cameras offer hemispheric views

FROM the point of view of image quality, would you argue hemispheric cameras are the best option to provide all-round surveillance in bigger areas – such as shopping centres, airport retail precincts, universities and the like? Or are we better to think about multiple cameras with smaller fields of view?

Let's get this straight right from the start – hemispheric cameras with 360-degree fields of view spread their pixels. Depending on sensor size this pixel spread will render the image soft from very close in to quite close in – less than 10m and in some cases closer still. As light falls, detail will be lost earlier, too. Depending on what you are trying to achieve, this softness in larger applications may mean no court-admissible face recognition. 

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Thu
31
Aug
JohnA's picture

Crushed Blacks: Dealing With Detail Loss in Dark Scenes

Crushed blacks may not only be evident in dark scenes
Crushed blacks may not only be evident in dark scenes

Something I see a lot of with video surveillance is a complete lack of detail in the dark regions of a scene. This need not be at night but can happen when part of the scene is overexposed and sometimes for no apparent reason at all. What do you think is the cause of this loss of detail and how can it be rectified?

It sounds like crushed blacks – essentially the black point of an image is being shifted so the dark regions of the scene are all represented as being devoid of light – and thus stripped of detail. It’s important to bear in mind here that crushed blacks are not about tone but about detail. This may be caused by engineering, improper camera settings, or poor monitor calibration. Blacks may also be crushed in software to enhance the appearance of other parts of the scene, reducing the appearance of over exposure and increasing contrast and saturation. 

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Wed
23
Aug
JohnA's picture

Samsung Wisenet X XNO-8080R Bullet Camera: First Impressions

Samsung XNO-8080R bullet camera
Samsung XNO-8080R bullet camera

Samsung Wisenet X XNO-8080R is a 5MP bullet camera with WiseStream II support, a speedy F1.2 motorised varifocal lens with a range of 3.7-9.4mm, 30ips of resolution, H.264 and H.265 compression, 50m IR range, IP67/IP66, NEMA 4X and IK10 ratings against weather and vandalism, and video analytics including loitering, sound classification, fog detection, digital auto tracking and tampering. 

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Wed
23
Aug
JohnA's picture

Pros and Cons of Wide Angle CCTV Camera Lenses

Wide angle lenses should be matched with appropriate applications
Wide angle lenses should be matched with appropriate applications

As a long-term reader of SEN and a CCTV installer, I get the feeling you’re not in favour of wide angle lenses because of their negative characteristics. Are there conditions in which wide angle lenses are ideal?

A CAMERA lens is ideal if it gives court admissible evidence such as face recognition, from the front to the rear of its assigned target area. Every lens is a double-edged sword. Long focal lengths concentrate pixels and give lovely compression at huge distances but you can rob some poor soul under the camera’s nose and it will not see you.

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Wed
09
Aug
JohnA's picture

High Resolution Video Surveillance: The More the Better?

High resolution video surveillance - 4K from Sony
High resolution video surveillance - 4K from Sony

Video surveillance is becoming more pervasive and the more automated management systems become the greater the requirement becomes for high quality video footage that allows the best possible situational awareness for security response teams and for later investigations. High quality means higher resolution – anything above 3MP.

RESOLUTION is vital in video surveillance – it’s not everything all the time but all other things being equal, more resolution is better. It used to be that end users desiring high resolution video surveillance were required to invest enormous sums of money, or compromise on frame rate, bitrate or storage but times have changed over the past 5 years. You can know buy a 4K CCTV camera for an extremely competitive price that offers full frame rate, good low light performance, moderate bitrates, thanks to smart codecs and H.265. 

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Fri
14
Jul
JohnA's picture

Review: Bosch MIC IP Starlight 7000 HD PTZ

Bosch MIC IP Starlight 7000 HD is a powerful surveillance solution
Bosch MIC IP Starlight 7000 HD is a powerful surveillance solution

Bosch’s MIC IP Starlight 7000 HD is a special video surveillance camera that puts huge power into the hands of operators. It’s flexible, easy to drive, has a quality camera and lens, does well against backlight and in low light. There are particular applications for which it’s likely no other camera will do. 

PTZ cameras are fun to review because they are so flexible in terms of their capabilities and the flexibility of this Bosch MIC PTZ made it the most fun of all. This is a strong surveillance solution, offering operation in layers. It’s tough as an old boot but there’s no scrimping when it comes to the camera system. There’s no scrimping when it comes to the lighting system, either, but more on that later. 

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Fri
07
Jul
JohnA's picture

Affordable Video Surveillance: Plug and Pray?

Plug and play video surveillance solutions have their merits.
Plug and play video surveillance solutions have their merits.

Plug and play video surveillance is a kind of digital Holy Grail and an implicit recognition of the fact end-to-end analogue CCTV solutions have certain key advantages for smaller installers, including simplicity of installation, modest hardware outlays and easy operation. 

CAN plug and play IP solutions match the fundamental simplicity of analogue? It’s an interesting question because there are some real variables. For PnP to match analogue it must be very inexpensive. Yet even the most basic and affordable PnP CCTV solutions – think DVR and 4 cameras – offer the end user search functionalities that traditional analogue can never match. And just to shove a broomstick through the spokes, there’s also digital analogue, which offers analogue simplicity with digital resolution offering improved searching via digital zoom. 

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