Hey folks,
Looking at some Amcrest cameras for a project. It seems the only way to get narrow FOV is with varifocal lenses. For example, on the IP8M-VT2679EW-AI it advertises a F1.5 Max Aperture and 36°~138° viewing angle; 5X Optical Zoom
At max zoom, what is the Aperture then? I can't find this on the tech sheet, and since low light performance is key for my application I am cautious to throw away performance on an already relatively large sensor by zooming in and stepping down the aperture resulting in a darker image.
Impact of varifocal cameras on apeture and exposure
Re: Impact of varifocal cameras on apeture and exposure
Hello and Welcome to the forum..
So the Max is 1.5 so that is going to be the Zoomed in point.
Most times that data can be found on cameras lens it self and or even the data sheet..
However because this data isn't on the Website in the data sheet and I don't own one to see if there might be any extra info in the manual it comes with I will explain on what I know from my own cameras with Vari-Focal lens and give a general idea for this camera..
For a Typical consumer-grade Varifocal lenses, the max aperture narrows as the focal length increases. Commonly, a lens that starts at f/1.5 at its widest will often have an aperture of around f/2.8 to f/4.0 at it most telephoto ssetting. The exact aperture at 13.5mm would depend on the specific optical design and the amount of light the lens can gather. Because it is an 8mp camera it most likely would be f/4.0
To be honest, The counter part Bullet camera that is also offered at the same price looks like it might offer little better light intake and would make sense with it being a longer body for a larger lens area. Personally would buy the Bullet.
So the Max is 1.5 so that is going to be the Zoomed in point.
Most times that data can be found on cameras lens it self and or even the data sheet..
However because this data isn't on the Website in the data sheet and I don't own one to see if there might be any extra info in the manual it comes with I will explain on what I know from my own cameras with Vari-Focal lens and give a general idea for this camera..
For a Typical consumer-grade Varifocal lenses, the max aperture narrows as the focal length increases. Commonly, a lens that starts at f/1.5 at its widest will often have an aperture of around f/2.8 to f/4.0 at it most telephoto ssetting. The exact aperture at 13.5mm would depend on the specific optical design and the amount of light the lens can gather. Because it is an 8mp camera it most likely would be f/4.0
To be honest, The counter part Bullet camera that is also offered at the same price looks like it might offer little better light intake and would make sense with it being a longer body for a larger lens area. Personally would buy the Bullet.
Be Safe.