Below is “make a portable spy scope” video tutorial. This video explained us about how to capture an image in long distance. If your camera zoom is not big enough, this is the solution. What we need only a cellphone (have camera feature), binocular, 2 tripods, binocular holder, and belt clip.
To assemble the device, put the binocular into the tripot using binocular holder. Then put the cellphone into the tripot using the belt clip. What you need now just alligning the binocular into cellphone camera carefully to capture the image. Now you have a portable spy scope.