2.8-12mm vari-focal lens

[novelwolf]

Hi,

I need a cam to zoom at an object (gate) 90 feet away. Not interested in a PTZ as i wont be using it to look at anything else.

i saw this camera:

1.3 MP Vandal-Resistant Network Dome Camera

Hikvision’s DS-2CD2712FWD-I Vandal-Resistant Network Dome Camera provides important new technology for any security application. The 2.8 to 12 mm lens option provides 80° to 28.7° viewing angles.

us.hikvision.com

I has the the following main feature:
2.8-12mm vari-focal lens

Would i be able to:
1) Zoom in to view a gate 90 feet away?
2) Maintain the zoom even if it loses power briefly ( like an outage), but then comes back online?
3) Should i go for a manual zoom or motorized zoom?

Thanks
K

 

[alastairstevenson]

i saw this camera:

That's an old, low-resolution dome with poor low-light capability.
You'd be so much better with a current model high-resolution low-light camera, of which there are quite a few reviews on the forum.

To answer your query about whether a camera would provide a good enough image for your target, try the simulation tool here :

IPVM Designer / Calculator

Using Google Maps, layout and design cameras, choosing from 10,000+ models, delivering FoV and image quality previews plus export to PDF, Powerpoint and more

calculator.ipvm.com

 

[mech]

If your system has interoperability with non-Hikvision cameras, try the IPVM Camera Calculator and throw in the IPC-HFW5241E-Z12E from their database. This is a Dahua bullet camera with an extra-long-range lens and decent low-light sensitivity. @EMPIRETECANDY has them listed here if it looks like a contender: US $229.99 5% OFF|2019 New Arriving Model IPC HFW5241E Z12E 2MP Starlight WDR IR Bullet AI Network Camera ,free DHL shipping-in Surveillance Cameras from Security & Protection on AliExpress It's 2MP but will be able to land all the pixels on a gate at 90 feet with no waste.

Along with that, if you needed a very long-range and powerful infrared emitter to assist the camera's own IR, CMVision IR-200 is uncommonly powerful and directional, and easily found on Amazon.

 

[novelwolf]

Ok thanks.
Question: does the varifocal mean that once I set the zoom, it will save the setting and I won’t have to keep adjusting the zoom setting if I have a power interruption?

Also can the “mm” value be converted into distance I.e. feet or meters? The tool will help with that?

thanks

 

[mech]

For a Dahua varifocal camera, the short answer is it should stay at the zoom you've chosen. You can have it hold different zooms for Day and Night modes if you like.

Try out this circle calculator and put in 90 as your radius and goof around with the angle until you get the horizontal field of view you need: Circle Calculator - Metric Now compare this to the field of view of whatever cameras you're looking into. A 13-degree FOV (about 20 feet wide) would be right up the 5231 Z12's alley, it can do that. Alternately, you can put in the angle of the camera at maximum zoom, and see the horizontal coverage you'd get (top arc length).