Arecont Vision MicroDome Duo Tested
Arecont Vision is back with another multi-head camera, this time thinking smaller with the MicroDome Duo [link no longer available], a two-imager model, with the tagline "Look both ways for hallway surveillance", a form factor rarely seen in surveillance.
However, given Arecont's historic (and continuing) reputation, the question is how well this novel approach stacks up against single imager models from other manufacturers.
We bought and tested the 1080p MicroDome Duo (AV4655) recommended by Arecont, against compact domes from Axis and Hikvision, seeing how it compares in full light, low light, and bandwidth consumption, and how well it fits the large or odd shaped intended scenes.
Like Arecont's Omni, the MicroDome Duo is an uncommon concept with a number of potential applications in larger or odd shaped areas which may be more expensive or less aesthetically pleasing to cover with multiple single cameras.
However, compared to current dome models, the AV4655DN had several disadvantages which outweigh these benefits:
- Overexposure/white balance issues: During the day, in an evenly lit office (100-300lx) images were overexposed, making objects easily recognizable/legible in other cameras difficult to read/identify. Additionally, poor white balance resulted in discoloration.
- Poor low light performance: At night (~0.1lx), images were essentially black, providing no detection or details of the subject at all, while competitive non-IR domes (e.g. Axis M3045) produced solid detection/limited details.
- High bandwidth: Compared to others, the MicroDome Duo's daytime bandwidth was very high, with Axis and Hikvision ~66% and 50% lower, respectively. Arecont's nighttime bandwidth was much lower, but this is in large part due to the nearly black images produced.
- Higher price: The MicroDome Duo is expensive when compared to two separate domes from lower cost manufacturers such as Hikvision, Dahua, or even Axis' M30 series, all of which generally offer better image quality and lower bitrates than the Arecont model.
The AV4655DN-28 sells for ~$650 online. By contrast, single imager 1080p domes (such as Hanwha, Dahua, or Hikvision) may be found online for under $200, though also require separate cables, switch ports, VMS/NVR licenses, and installation.
Including all these factors, the AV4655DN's price is likely approximately similar or slightly higher than using two lower cost cameras.
Note that there are few other dual camera options available. Mobotix offers one, the D15 DualDome, though it is MxPEG/MJPEG only and more expensive (~$900+ online), though also higher resolution (6MP imagers) and includes audio, I/O, and other features the MicroDome Duo does not. Hikvision also announced a dual imager model more than a year ago, called MonoVu, though it is still unavailable.
The MicroDome Duo's form factor is different from most dome models, essentially two minidomes merged together, with separate dome bubbles. The imagers have independent gimbals which can be adjusted separately, freely angled and rotated. Note that multiple lens options are available, as well, ranging from wide angle 2.1mm (113°) to telephoto 16mm (15°).
We look at the camera in this physical overview video:
The relative size of the camera is shown here, taller and wider than Axis and Hikvision minidome models:
The MicroDome Duo's sensors are contained in essentially spherical gimbals which allow them to be freely positioned and rotated. We set up the camera to cover two key use cases in our office:
First, we covered an open office area ~90' long, aiming the two cameras opposite each other. In this scene, brightness/contrast were uneven, which can be seen on the overexposed walls of the office to the left. These issues were common, seen in our other sample scene as well as image quality comparative testing (below).
Download a clip of this scene (~289 MB)
Second, we viewed an entry door and adjacent hallway, normally covered by two cameras. Again, some overexposure was present in the hallway. In this example, the left imager was rotated 90° into corridor mode to better cover the hallway without wasted FOV areas.
Note that the 4655DN is not true WDR (though a WDR model is available, the 4656). This example is intended to show coverage/usability, not WDR performance.
Download an export of this scene (~103 MB)
We tested the AV4655 against competitive dome models to see how image quality compares in full light and low light scenes, using this FOV:
With lights on, ~300lx, the Arecont camera shows noticeable discoloration and overexposure of lower lines of the test chart compared to others, moderately reducing details.
At ~0.1lx, the Arecont camera's image is almost completely black, despite being specified with a 0.02lx minimum illumination rating. The Axis M3045-V easily detects the subject, though no details available due to digital noise, and the Hikvision 2522 shows some rough subject details and 1-2 lines of legible text due to its built in IR.
The AV4655DN's daytime bitrates were much higher than other models tested (comparing only a single imager), over 1.2 Mb/s in well lit scenes, where others used 50-60% less bandwidth. At night, the AV4655's bitrate dropped to be the lowest among cameras tested, but no usable images were produced.
Arecont cameras were tested using default settings except for exposure mode, which was set to High Speed / 33ms to avoid blur due to slow shutter.
The following firmware versions were used in this test:
- Arecont AV4655DN-28: 65201
- Axis M3045-V: 220.127.116.11
- Hikvision DS-2CD2522WD-I: 5.4.1