Subscriber Discussion

In A Long Hallway: A Lot Of Cheaper Cameras Or A Few Better Cameras In Hallway Mode?

DM
David Matyas
Feb 17, 2015

Im in the porcess of spec'ing out a camera system that will have a few 250 foot hallways.

I can either put in multiple (close to 8) cheaper (hikvision) 3mp cameras. Or I can put in 3 higher end (avigilon) cameras in hallway mode.

In a case like this, what do you like doing?

Thanks

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Ethan Ace
Feb 17, 2015

Can you not run the Hikvision's in hallway mode? They should support it, depending on firmware.

Also: what's in the hallway? Do you need every inch covered or just key points in it?

DM
David Matyas
Feb 18, 2015

I have mainly dealt with the DS-2CD2132 series and I didn't see that they have hallway mode.

The hallway is in a school, and the staff just want to be able to see what is going on, if someone is in the hallway during classes, etc... They do not need to see the face of someone all the way down.

JH
John Honovich
Feb 17, 2015
IPVM

David, why would higher or lower end cameras make a difference in a hallway specifically? Is there some specific feature tradeoff?

Here are 240+ cameras that support corridor mode. Btw, are you using Avigilon's VMS? How else are you going to get their cameras to do hallway / corridor mode otherwise?

DM
David Matyas
Feb 18, 2015

Honestly in the past, I have mainly dealt with Hikvision, Acti, Vivotek and Avigilon. Acti and Vivotek I have dropped for Hikvision. And so far I didn't see that Hikvision was able to do hallway mode properly. I have used Avigilon in the past in hallway mode and was pretty happy with it. Using their VMS, I was able to zoom in during playback and it didn't pixilate that much.

I was going to offer them Avigilons VMS as one of the options. I didn't know that I can't do hallway mode with Avigilon cameras with a non Avigilon VMS.

Thanks

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Paul Grefenstette
Feb 17, 2015

The bigger question for those 2 options would be does the customer want to do pixel search on these hallways or can they get away with just doing a regular search to pull video as the hik cameras cant do pixel in avigilon but the avigilon camera can obviously. But the Hikvision cameras do work well with Avigilon, I have a system I am putting in next week with 11 of the turrent style cameras (3mp 4mm) using Avigilon ACC5 for an industrial client that was on a tight budget and we gave them both options on cameras and they picked hik

DM
David Matyas
Feb 18, 2015

I explained to them about pixel search but they dont think they need it. I am able to do a motion search using Hikvision/Avigilon.

I too have used hikvision/avigilon combo in the past. It lets me offer a great NVR while saving the customer money on the cameras.

MI
Matt Ion
Feb 18, 2015

I don't get why Avigilon would need specific support for hallway mode... I've been doing it for a couple years now with both Dahua and Axis cameras on Vigil recorders, I just use the function in the camera to rotate the image 90 degrees, and Vigil sees and records it as it would any other stream, it's just tall and narrow - 1080 x 1920 rather than 1920 x 1080, for example.

One thing with hallways, unless there are a lot of side doors you need to cover, you should generally be able to get away with one camera at either end - you should have good enough image to see what happened along the length of it, and anyone in there will have to pass the camera to get out. 250' long, you may need to add one or two spaced along the length of it just to fill in, but identifying people shouldn't require massive coverage, you just need to get them at the choke points.

JH
John Honovich
Feb 18, 2015
IPVM

"I don't get why Avigilon would need specific support for hallway mode..."

Presumably a business decision rather than a technical one, so that you only get that feature if you use the whole Avigilon 'solution'.

But yes, since a number of competitors provide that on the camera side, it's a limitation.

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Jon Dillabaugh
Feb 18, 2015
Pro Focus LLC

Just my opinion, but I would look into staggering 180 degree wall mounted panoramics, similar to this:

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JH
John Honovich
Feb 18, 2015
IPVM

That's a very novel solution!

My gut feel is that it would be bad though :)

Mainly my concern is that you are spreading the pixels too 'thin', wasting them on the opposing walls, ceiling, etc.. For example, a 1080p 180° camera delivers only 30ppf at just 10' away. By contrast, a conventional 1080p 60° camera delivers 30ppf at ~55' away.
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Jon Dillabaugh
Feb 18, 2015
Pro Focus LLC

The issue I see in a full hallway is there is little chance you will see unobstructed for that 55' distance. You are more likely to see only 10-20' unobstructed anyways.

As far as wasting FOV on the floors and ceilings, I don't see it that way. I look at it from the perspective that I don't want blind spots. I don't want it to be easy to obscure a camera without being seen by another either. Having the opposing, staggered views acheives this IMO.

All that said, it was just an off the cuff idea I had when reading the OP. I'm not saying it is "THE" way, just one way I would model it and see what the coverages look like.

Also, if your VMS doesn't support dewarping, a lot of models do support camera side dewarping. I tried seaching Finder for these models, but dewarping isn't a search option.

If you are opposed to panoramics all together, then simply stagger 2.8mm wide angles in the same manner, but you will need more to cover the same space. It all depends on how much pixel density you really need.

JH
John Honovich
Feb 18, 2015
IPVM

"The issue I see in a full hallway is there is little chance you will see unobstructed for that 55' distance. You are more likely to see only 10-20' unobstructed anyways."

Are you saying the dead space / spot in front of the camera from the zoom?

There's certainly going to be some but it won't be 3/4ths of the distance as your estimation implies.

"As far as wasting FOV on the floors and ceilings, I don't see it that way."

My point is that you will need many more cameras to maintain the same pixel density on target on the subject walking down the floor with a 180 approach.

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Jon Dillabaugh
Feb 19, 2015
Pro Focus LLC

John, when I say unobstructed, I mean there are likely other subjects in the way in a span of 55'. Lets say your object of interest is 20' away from the camera, which should be a rather high PPF, but there is someone taller at 16' away, blocking your shot. It is going to be fairly common over a 55' span. Especially in high school, crowded hallway.

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U
Undisclosed #1
Feb 18, 2015
IPVMU Certified

Seems like a lot of FOV going to the floor, ceiling and walls, no? Plus wide angle lens distortion and no-straight on face shot. Also hard to get a good situational view of the whole hall without viewing several cameras.

What are the benefits that you see?

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Paul Grefenstette
Feb 18, 2015

We have tried to make 360 and 180 cameras work in school hallway applications but it never results in a good solution so we always go with 2mp recessed domes in the drop ceiling and turn the image 90degrees(hallway mode) to get the best result -- 2mp is the best because of the 16:9 aspect ratio so you can flip it and get the best result just be aware of ceiling mounted exit signs and soffits when doing your walk-through design as those can get in the way of the best shot - good luck

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Jon Dillabaugh
Feb 18, 2015
Pro Focus LLC

Paul, in your installs, do you find you get a lot of "top-of-head" shots being ceiling mounted? That is the concern I would have with ceiling mounted cameras shooting subject nearby.

The other side of that coin is using a longer throw lens (>8mm) and getting a better angle for facial details, then you have issues with other people obstructing the view.

I haven't had one of these scenarios so I am just curious how it worked for you.

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Paul Grefenstette
Feb 18, 2015

You do get top of heads when they are directly under the camera but they are walkign down the hall so at most points you have a face shots so they can id students for incidents very easy

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Jon Dillabaugh
Feb 19, 2015
Pro Focus LLC

Do you have any notes about your camera angles? I'm wondering what your downward angle is for a ceiling mounted camera. My concern would be having to balance the downward angle, lens zoom, and frequency of subjects being obstructed by other, taller subjects in front of them when in a crowded hallway.

U
Undisclosed #2
Feb 23, 2015

I see a lot of installations where the cameras are at both end of the halls. Although the camera at one end may be able to see the door at the other end, the long distance may not yield a very clear view. Try ceiling or wall mounted cameras directed toward each other (more toward the middle of the hall). This should cut the distance to target and minimize blind spots (i.e. under the cameras). You may be able to cut the number of cameras as well.

MB
Michael Blumenson
Feb 23, 2015
IPVMU Certified

We have used the Mobotix Dual dome technologies for hallways for many years. It is not a cheap solution but if you factor in less network drops, less install labor, less VMS licensing it is an attractive option. I've been asking other camera manufacturers for years to provide another dual dome option but for some reason they resist or perhaps the request never reaches the right ears. Or maybe we are on an island liking this solution. The quad sensor options are overkill for hallways in my opinion.

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