Re: The iris of the eye cannot control the amount of light?
A good quality 35mm camera can probably adjust from f2 to f16 which would correspond to a change of light intensity of 64:1. If the pupil of the eye has a maximum diameter of 9mm, then the minimum would need to be about 1.1mm for the same result. The problem is that the camera has two more adjustments for light levels - the shutter speed and the film speed, so even for the camera the iris aperture is insufficient to manage all the expected variations in light levels.
According to this Wikipedia page
https://en.wikipedia.org/wiki/Adaptation_(eye) the human eye can handle a variation in light levels of 1,000,000,000:1. That would imply that the narrowest pupil would be about 0.0003mm. I have only looked closely at my own eyes, but my pupils do not have that range of adjustment. I find that if I stand in front of a mirror in a darkened room and use a small torch to adjust light intensity, my pupils vary in size by no more than about 2:1. Other Wikipedia pages say that the pupil dilates or constricts in response to pain, drugs, disease, interest and imagination.
I say that the main way that the eye adjusts for different light levels is in the individual light sensitive cells in the retina. If you use a digital camera to photograph something like a working wall light, I think you will find it impossible to obtain an image which looks the same as what you see with your eyes. The camera adjusts for light level but it can only adjust the entire image and not small parts of it.