2.8mm vs 3.6mm, which do you prefer for a fixed-lens?

CCTVCam

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@aristobrat that is a very good placement of the 2.8mm at the front door.
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I'd like to see it a few feet lower. Best height for capturing faces is face height!
 

tigerwillow1

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With the new 1/1.8" sensors out you need to consider the sensor size just as much as the focal length. For example, the new 4MP 6mm cameras with the 1/1.8" sensor have about the same FOV as a 3.6mm 2MP startlight using the 1/2.8" sensor.
 

aristobrat

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If I understand correctly, if I would like to see only the alley in front of my house, I would have to choose a 6mm fov camera(T5442TM-AS)?
So the 6mm would be a good choice, right?
Have you tried using IPVM Camera Calculator V3 to see?

I added the 5442 3.6MM (orange camera) to the front of my house (facing out), then added a second camera (5422 6MM, blue) and positioned it right on top of the other camera. You can see the difference in field-of-views between the two fixed lens sizes.

Screen Shot 2019-12-05 at 7.53.02 AM.png
 

Arjun

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How wide is your alley? Also what is the distance from front to back? A varifocal saved me the headache from trying out multiple fixed lens cameras

Sorry to revive this old thread, but I did not want to open another thread about the same subject.
If I understand correctly, if I would like to see only the alley in front of my house, I would have to choose a 6mm fov camera(T5442TM-AS)?
 

tibimakai

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I would really like to get a 4-5 MP vari-focal, but they are not available yet. All my other cameras are vari-focal. Since the 4-5 MP cameras are showing up, I thought why not buy one, at the front door, to be the best one there.
I have used that calculator, but I wasn't sure, if I used it correctly. There it lists three angles and not by millimeter. I wasn't sure which one is which. So am I right in assuming, that I need the 6mm? Alley width is a regular width alley, it is not wide.
 

aristobrat

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I have used that calculator, but I wasn't sure, if I used it correctly. There it lists three angles and not by millimeter. I wasn't sure which one is which. So am I right in assuming, that I need the 6mm? Alley width is a regular width alley, it is not wide.
Of the three angles, the widest is the 2.8mm, the middle is 3.6mm and the narrow one is 6mm. If you could post a Google maps image of your house/the alley it'd really help us "see" what you're working with.
 

tibimakai

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Actually I have a picture posted yesterday, but in the installation picture section. I will post it here as well. I'm also having issues placing this camera, at the porch "entrance". Not sure where to place it. I have marked it with an arrow, where I'm thinking that I may place it. The camera is wider, than the columns(3-3/4").
I don't want to go up in the attic and fish it down into the wall. I have a serious back issue. Initially that was the plan, to put the wedge camera there, but I won't do that anymore.
 

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tibimakai

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The narrower the fov, the better I can identify somebody from up close, right?
 

aristobrat

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The narrower the fov, the better I can identify somebody from up close, right?
That's usually true when talking about the same camera. A 5442 6mm will have a more narrow FOV and be able to ID further away than a 5442 2.8mm. You can test this on the IPVM calculator tool. As you drag the person icon to different distances the tool will show you two estimated images on the right with a PPF value between the images. The closer the PPF value is to 100 (or higher) the easier it should be for you to ID someone. A bigger focal length (i.e. 6mm vs 2.8mm) will give you more PPF (and also make the FOV more narrow).

I'm still a little lost about the "alley" .. are you talking about the walkway from your driveway/the street?

For the arrow you drew on the one photo, I know it's hard to show depth on the photo, but would the camera mount on the house where the arrow is or on the rail? And how would you run the wire to that location?

Here's how I have my front porch setup. It's not ideal, but it works well enough for everyone in the house. The bright light in the pic below is a camera mounted to a horizontal beam (which I imagine would be the porch ceiling in your case, which I know you don't want to do, but just wanted to show you how mine was setup). This porch camera points towards the door. If you look above and to the right of that camera, you should see two LEDs from a 5231 that covers the front yard. Both the porch and front yard cams catch folks as they walk up. Again, not ideal as porch setups go because nothing's "in your face" when on the porch, but I don't have any easy way to get Ethernet down a wall closer to the door.




View from porch camera:

PIR 2019-12-04 01.04.16.432 PM.jpg

View from front camera (washed out because setting sun this time of year comes fully in shot for a few weeks).

Front 2019-12-05 03.44.08.20 PM.jpg
 

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tibimakai

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Here is another picture, with more explanations.
The Ethernet cable I will run it on the inside of the beam and down on the column. I may use a PVC pipe, with some clamps.
On the left side of the porch, on the garage wall, I have a 5321 there, that is like your right camera, overviewing the porch.
All I need is to view that narrow angle in front of my house.
I have the 59225 right on the corner of the garage(not pictured here, old picture from previous owner), also a 5231 between the garage door and corner. Others may have two light next to the garage door, I have two 521s there ;)
 

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tibimakai

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Yes, I'm kind of made up my mind about the fake birdhouse. I just need to find the right house. The 5231R-Z has a ball diameter of 3.540", but I need the size for the 5442.
 

CCTVCam

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I'd mount it higher personally. A bird house wouldn't look correct mounted that low but simply from a camera perspective, you get the best facial shot from straight on. So around head height to slightly above / below is ideal. Most go slightly above just because the extra height adds a little security and pointing down reduces glare.

Looking at your last photo, I'd also raise the question of what you're trying to protect here, the house or the cars?

The 5231R seems to be pointing back towards the front door / windows. That's good but leaves the footpath, cars and garage as areas to consider along with the garden - a thief won't necessarily use the path if they realise there is surveillance or strong path lighting.

Looking at the Google overview from earlier in post #30, you have vulnerabilities along the right side also. Your own picture also shows the garage will mask the view of the cars. I don't really see this as a simple 2 camera set up if you want total coverage. The house shape is awkward to cover given that's it's not a simple square area. I'm personally a great fan of crossing camera views as then each camera protects the next one from any physical interference, although it does often take more cameras. If you were going to use disguised cameras then a birdhouse in the corner on the fence to the left of the garage (when viewed as per google standing from the road), with the camera looking back towards the road, depending on fence height, might provide good coverage of cars / garage and although it would be vulnerable to someone attacking it from over the next door fence, as a bird house, it's probably not going to be a target unless obviously not a birdhouse. I like the position of the 5231R. I'm not so keen on the porch camera or the uncovered area to the right. I'd be tempted to move the porch camera back onto the house under the porch almost like a doorbell view, so it's covered by the 5231 although it could still be bird housed. It would still get a great view of the path and should be shielded more from the sun. Your drawing shows it at an angle although realistically as a birdhouse, it's going to be square to the wall or porch frame if the original mounting position so that might be an unrealistic view you've marked there. The vulnerable area will the right hand side of the house although the 5231 should cover that side of the porch, just not access to any side window or the rear from up the side. Just some thoughts although I defer to those with more experience here.
 
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