I have a x50 zoom camera and here is some specs of the camera and lens:

  • Focal length: 6 mm ~ 300 mm
  • Field of view: 58.4° ~ 1.4°
  • Resolution: 2 MP

I drew a scheme to explain my question properly, you can see below:

enter image description here

I have a 500 meter diameter circle area 6 km distance to my camera. My question is that is this camera able to zoom to this target area or not ? Can we calculate this with these camera specs ? If yes how ?

Thank you all.

  • 1
    On what size sensor? You won't do it on full frame & looking out of my back window to as far as I can see, maybe 1.5km, I doubt it on an APS-C. 2MP sounds like something very small or very old, but the sensor size is what will enable the calculation. [Whether you can discern anything useful at that distance would be a different matter]
    – Tetsujin
    Jun 16, 2021 at 7:24
  • @Tetsujin In datasheet of camera, sensor size not mentioned. But with focal length and field of view, isn't it possible to calculate sensor size ? Jun 16, 2021 at 7:29
  • 1
    @YunusTemurlenk The focal length essentially scales with sensor size. A 150mm lens on a Micro Four Thirds has the same field of view as a 300mm lens on a full frame sensor.
    – wilkgr
    Jun 16, 2021 at 10:12
  • @wilkgr so lens and sensor is becoming closer according to focal length and also field of view angle by keeping sensor size distance. Field of view angle and focal length are changing by keeping a ratio between each other ? Jun 16, 2021 at 12:20
  • @YunusTemurlenk Wikipedia can explain it much better than I can, sorry: en.wikipedia.org/wiki/Crop_factor
    – wilkgr
    Jun 17, 2021 at 8:16

1 Answer 1


By calculation angle (which is to the camera) of this triangle is around 4.7 degree.

So on one of the length of zoom you will be able to fill the frame with this object.

But the quality on such distance is under question....

  • 1
    @YunusTemurlenk, correct, will edit my answer Jun 16, 2021 at 7:34
  • 1
    Thanks again. I ll accept this answer Romeo but one more question mark. I also thought in this way. Field of view we calculated which is 4.7 degree between the 58.4° ~ 1.4° . But there are many cameras even x30 x20 zoom cameras satisfy 4.7 degree field of angle but of course their focal length is smaller. So whats the relation with focal length and distance. Longer focal length difference(higher zoom range) is better to catch or this only increase the quality of image = Jun 16, 2021 at 7:39
  • 2
    @YunusTemurlenk, longer focal length give you the option to project on sensor bigger image so have bigger object on the image. But my personal observation show me those superzooms do not provide good quality especially on long end Jun 16, 2021 at 8:01
  • 2
    @YunusTemurlenk Comparing X50, X30, or X20 is meaningless unless all of them begin at the same focal length, and they very often don't. Focal length is the key number, not the ratio between the widest and narrowest fields of view provided by a zoom lens. It's quite possible a 20X lens goes from 20mm to 400mm in focal length while a 50X lens goes from only 5mm to 250mm.
    – Michael C
    Jun 16, 2021 at 14:38
  • 5
    @RomeoNinov Not only are such lenses usually of low quality, but even with the best prime lenses at 6 km subject distance atmospheric conditions often degrade image quality significantly.
    – Michael C
    Jun 16, 2021 at 14:41

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