Advice needed on focal length for 5442

Rubke

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Dear all,

Already got an IPC-T5442T-ASE 2.8mm as an overview camera for watching my driveway and the cars. It's a great camera.

I'd like to buy another one, so I can also guard my frontdoor and garden. Which makes it a little bit difficult is the fact that the public road is right in front, and there is a big tree in the garden. That makes it difficult to attach a camera to the house. Therefore I placed a pole at the beginning of the driveway on which I'd like to attach another 5442 from Andy. I'm not sure on the focal length, hopefully you can give me some advice. I've circled the current 5442 above the driveway (note that in some pictures it is still an old Foscam and not the actual 5442). Distance from pole to front door is about 7 to 8 meters.

Frontview of the house:

More sideways, showing the pole:

Attached to the pole:

Old Foscam attached to the pole (2.8 mm):


2.8 mm would be too wide I guess. Image of the frontdoor and garden is relatively small, and I don't need to film the other camera. In the corner there is a flood light that is triggered by motion. I don't think that one needs to be filmed as well. So I guess a 3.6 mm or 6 mm might be better, or even a varifocal? But which one?

The current camera would also film the camera on the pole. Will it be blinded by the IR?

All the advice is more than welcome!
 
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sebastiantombs

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You could try a 3.6mm which will give a little tighter FOV. You will need to prune the vegetation or the camera will be blinded when using IR. The other camera will "see" the IR of this camera as a bright spot, but it should, note I say "should", not seriously effect the video. Here's a screen cap from a 3241 zoomed in about half way looking at a 5442B-ZE that's about 15 meters away.

5442-IR.JPG

A quick, rough, guide for focal length versus distance for field of view -

lens sizes.JPG
 

nelgnl

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Aren't you able to mount a 2.8 mm turret/dome next to that downspout (regenpijp), pointing it towards your door? It's even closer to people that will walk to your front door or kitchen window.
 

Rubke

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Aren't you able to mount a 2.8 mm turret/dome next to that downspout (regenpijp), pointing it towards your door? It's even closer to people that will walk to your front door or kitchen window.
It would be really hard getting network at that location. Besides that, I would still miss everything happening on the small piece of public road in front of my garden because of the big tree blocking the view. Therefore I figured that this pole over there would give me better possibilities.

@sebastiantombs : indeed, I placed the pole already a little while ago, so I'd need to cut away some of the vegetation. Hopefully not too much, so the camera won't be too obvious. When choosing a 3.6 mm I guess I would still see a lot of the cars as wel as off the side of the house. This is in my opinion not necesarily necesary, as the car is already captured by the 2.8 mm. In this case my focus is on the front garden and the frontdoor, not so much on the car. Would 3.6 mm be good enough, or 6 mm even better?
 

sebastiantombs

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That is for you to decide. A simple solution would be to use a 5442T-ZE so you can set the focal length exactly where you need it. No guessing wrong that way.

Personally, I have three cameras covering our vehicles. One is specifically installed for that purpose, and the other two include the vehicles in their view. Generally two cameras are used for vehicle over watch, one on each side and with opposing views so there is no blank/hidden areas at all.
 

bradner

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Depends or your lighting situation or the trade-off but it's still a darn good camera.
 

Rubke

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Varifocal with the use of @bp2008 Dahua sunset/sunrise utility. Day time = wide FOV. Night time = tighter FOV, away from oncoming headlights.
That's a nice idea! However, you're not allowed to capture the public road without a reason here, so I was planning on filming as less as possible of the public road. Therefore headlights won't be a problem. Still in doubt, I'd prefer a fixed focal length camera because of the light sensitivity, but I'm not sure whether 3.6 mm will be enough for capturing everything that happens at the frontdoor/garden.
 

sebastiantombs

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The difference in light sensitivity is meaningless. It's nowhere nearly enough to be noticeable. If your a purist, yes there is a small difference compared to a fixed lens, but that's what tuning a camera is all about, getting the best out of it under all circumstances. A marginally better F rating may be a bad tradeoff if the FOV isn't what you want or need.
 

Arjun

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Buy a varifocal camera. I will never buy a fixed lens camera again, just isn't worth it. Not a drastic difference in size. The varifocal has better depth of field and has versatility. The 5442 varifocal turret is the way to go.
 

The Automation Guy

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Use IPVM Camera Calculator to overlay different camera models on a satellite image of your property. If you overlay a variable focal length camera, you can adjust the settings and see exactly how it changes the coverage. I have found it to be very accurate. IMHO it's the easiest way to figure out where to install a camera and what focal length to use.

Also watch the PPF (pixels per face) number (the higher the better) as it is a great indication of the DORI principal.
 
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Rubke

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What do you guys think would be optimal height for camera positioning? I was thinking around 2.4 meter, which is about the same height as the one above the driveway. However, the pole itself is around 3 meter so I could go higher with the camera, also making it harder for bystanders to get to it.
 

wittaj

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2.4 meters or lower would be ideal.

Most people are oblivious to cameras, so mounting higher to try to prevent damage usually means then that your footage gets the tops of heads and hoodies, which doesn't do much good either.

We try to have every camera protected by another camera, so in the event someone is dumb enough to mess with a camera then you have them picked up on another camera.
 
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