A new form of iris control, called P-Iris, is emerging as a challenger to manual and auto iris lenses. P-Iris can more 'precisely' control the aperture size than auto iris lenses. P-Iris providers claim this can provide important quality benefits. For the P-Iris 'pitch', see Axis's P-Iris whitepaper.

While Axis introduced P-Iris, many manufacturers are going to offer cameras with P-Iris lenses. For instance, Vivotek and CBC have already announced P-Iris offerings. From our conversations with other camera manufacturers, quite a number of other companies will release P-Iris enabled cameras later this year.

We recently tested the Axis P1347 which includes a P-Iris lens. In addition to testing that camera's general performance, we were interested in understanding how much of a benefit the P-Iris lenses provided specifically.

Test Methodology

We executed a series of test cases relevant to video surveillance applications comparing P-Iris against DC Iris and Manual Iris performance.

For each test case, we used the same P1347 camera with the same settings, cycling through a p-iris, dc-iris and manual-iris lens. We then review the results, and provide a video analyzing the differences found (if any) for each of the test cases. We key in on what impact to video surveillance, if any, these differences might provide.

Megapixel lenses tested:

• P-Iris: Kowa F1.6 / 3.5 - 10mm (LMVZ3510-IR)
• DC-Iris: Fujinon F1.4 / 2.8 - 12mm (FVL2812AI-MP)
• Manual-Iris: Tamron F1.6 / 4.5 - 10mm

Note: The P-Iris lens was included with the Axis P1347. The Manual iris lens was set to fully open for all tests.

We performed tests across 6 scenes:

• Daytime/Indoor
• Low-Light/Indoor
• Daytime/Outdoor
• Daytime/Outdoor/Bright
• Nighttime/Outdoor
• Depth of Field

The series consists of three different daytime tests. The daytime/indoor shot is a basic indoor scene with a fairly narrow FoV. The daytime/outdoor is of a busy traffic scene during the day featuring a wide field of view and plenty of objects in motion. The daytime/outdoor/bright features a park scene large degree of direct sunlight into the camera lens.

Within the series is also a nighttime/outdoor and a low-light/indoor test. The nighttime/outdoor scene is identical to the daytime/outdoor scene, except that it is at night and the camera switches to b/w mode. The low-light scene is a 1.0 lux and 0.3 lux environment.

Finally, we performed a depth of field test. This scene is of a long hallway roughly 50ft in length. This test includes four (4) different scenarios. Two of them focused the lenses to a rear-field subject, and the other two focused on a near-field subject.

The combination of these tests provide a broad range of common scenarios to demonstrate the potential differences P-Iris might provide.