Benefit of a dome cameras instead of a turrets or bullets

[Dave Lonsdale]

After several years, I am going to add a couple more cameras to my system at home (currently a mixture of 11 x Dahuas) and am researching my preferred choice. Most forum members appear to favour turrets. However, my bullets and turrets are plagued by cobwebs, even soon after climbing the ladder to spray with spider deterrent. I have two domes that never get cobwebs. Do other forum members also find this to be the case?

Two are black face PTZs that spin daily to throw off cobwebs and discourage spiders but are far too expensive. To also mention, I tend to use discrete IR illuminators instead of internal IR to avoid reflections.

 

[fenderman]

After several years, I am going to add a couple more cameras to my system at home (currently a mixture of 11 x Dahuas) and am researching my preferred choice. Most forum members appear to favour turrets. However, my bullets and turrets are plagued by cobwebs, even soon after climbing the ladder to spray with spider deterrent. I have two domes that never get cobwebs. Do other forum members also find this to be the case?

Two are black face PTZs that spin daily to throw off cobwebs and discourage spiders but are far too expensive. To also mention, I tend to use discrete IR illuminators instead of internal IR to avoid reflections.

IF your turrets and bullets have an ir ring around the lens that would cause excess spider web problems. Modern turret and bullet design with a single our double IR led away from the lens have very little issues with spiders. Domes have web problems in addition to other ir reflection issues.

 

[Dave Lonsdale]

Many thanks for your feedback fenderman, you have now made me think a bit harder. I don’t use the built-in IR but it’s true to say that my two turrets also don’t normally suffer with cobwebs. It could be the problem especially with two of my four HFW8231E-Z bullets is their location on the house wall, each immediately above large shrubs - holding a larder of grubs for the spiders. I notice the cobwebs hang down from the fully extended sun/rain canopies - I’ve now tried retracting them.

I need a narrow field of view for a new camera looking down my longish drive so if retracting the canopy and being on a clear stretch of wall is successful, I will then be very tempted by the B5442E-Z4E. 1/1.8, 4MP, 43-15 FOV and 0.0006 in colour would fit the bill although severely damage the wallet. Oh, plus a suitably longish range discrete illuminator. I guess, like my 8231’s, the 5442 will have built in IR on each corner (2 near an 2 far) but suffer from rain, snow, fog, bugs (and of course a few spiders occasionally).

Thanks again fenderman for making me think.

 

[mech]

If you need an off-the-shelf long-range IR illuminator, the CMvision IR200 is very powerful and directional. It isn't as highly weather-sealed as some, so mounting it under an eave and not power-washing it would be best. Some time ago I contrasted the IR200 and another long-range emitter with the stock IR on a typical camera, here is some video:



Another note on the IR200: its photocell may not turn the IR on until it's very dark out. You can encourage it to turn on sooner by darkening or obstructing the section of glass that the photocell is looking through. Sticking a patch of masking tape over the glass there, and darkening it with a black marking pen if needed, is a simple way to do that.

Also, what I see as the main benefit of domes is that a vandal cannot re-aim the camera with a stick or by hand. In the case of a Dahua, they'd need a specific hollow-tip Torx tool to remove the dome first. It's also that much harder to steal the camera outright. My own domes have had far less spiderweb problems than my turrets and bullets, and my main downside is that they seem more prone to getting dirty, with lens flares from the dome as a secondary issue. But they have their place.

 

[Dave Lonsdale]

Hi mech, thanks for your message. If I interpreted your video correctly, it looks like the IR200 has a very narrow spot beam and yet according to the spec it’s much broader. I want the illuminator to reach from the house down the drive to the road which is a distance of around 100ft. I think a field of view for the camera set to 20 degrees will be best, needing an even spread of illumination across this range and not giving rise to washed out faces.

I also have to say I doubt my wife would think the IR200 has a sufficiently aesthetically pleasing appearance to mount in a prominent position at the front of the house.

Good comments about the benefit of domes but to further balance the argument, rain droplets on the dome can sometimes spoil the image.

 

[sebastiantombs]

As far as a dome being more vandal resistant, if a miscreant can get to either a dome, turret or bullet with a baseball bat the camera is going down.

 

[mech]

Hi mech, thanks for your message. If I interpreted your video correctly, it looks like the IR200 has a very narrow spot beam and yet according to the spec it’s much broader. I want the illuminator to reach from the house down the drive to the road which is a distance of around 100ft. I think a field of view for the camera set to 20 degrees will be best, needing an even spread of illumination across this range and not giving rise to washed out faces.

I also have to say I doubt my wife would think the IR200 has a sufficiently aesthetically pleasing appearance to mount in a prominent position at the front of the house.

Good comments about the benefit of domes but to further balance the argument, rain droplets on the dome can sometimes spoil the image.

The IR200 is the first of the two spot beams in my video. I estimate its spread is less than 15 degrees, whatever CMvision may say. The third beam in the video is a Black Oak 2x2 emitter pod designed mainly for automotive use (no photocell). If you're planning to get the Z4E camera, you could start with its onboard infrared and see if it does what you want, then supplement it if it isn't satisfactory. A diffuser can soften up the CMvision's beam (something like rice paper), otherwise it is a laser cannon.

One strategy would be to have the camera's own IR illuminate the facial-identification range, and add a long-range IR which is offset from the camera's location, and aimed for the distant part of the scene. That way you have more infrared at long range, but it doesn't swamp a subject who is within face-identification range.