I think that it is interesting to explore the relationship between photography and reality. Reality is what exists, what is out there, in opposition to what is immaterial or not tangible. You can’t take a photograph of something that doesn’t exist in our physical dimensions. A photo is always an index pointing to something real, a trace of an event or a group of events that occurred in a particular time frame.
Which is the time frame? An answer could be that the time frame is the one that the shutter takes to trip from one side to the other of the film. This is not fully true: imagine a photograph of a person walking, with the sun visible in background. The photographer presses the shutter in the exact moment when the person’s head covers the sun, to have a backlight effect. What your eyes and the camera see is the person some billionths of a second after he was there and the sun 8 minutes after it emitted the light that now hits the film’s surface. The fact that these events are seen as happening together is a pure coincidence, depending from the fact that you’re much closer to the person than to the sun.
The paragraph above is needed to understand that knowledge is always relative to the position of the observer. A photograph taken from the Hubble telescope will show events that occurred thousands or millions of years from each other, as they were happening all at the same time. An alien sitting on the other side of the galaxy would see a completely different scenario.
These statements don’t hold true only for photography. It doesn’t matter if you write what happens, or record the sounds or just place these things in your memory and keep them there, there is an intrinsic distortion of the observer’s knowledge, therefore of his perception of reality, based solely on his position.
In most practical situations the difference in time will not play any role, but every image recording is a recording of the past even before the light hits the film surface or the retina of the eye. It might be interesting to notice that the 10 billionths of a second that the light takes to bounce off a person a few meters away and then arrive to the lens, are enough for a desktop PC to perform a handful of operations.
When I show the photograph of the person walking in front of the sun, am I showing something real? Yes, the event occurred in that particular time and was visible from a particular point in space. Like people gathering in a certain point, regardless of how much road they walked to get there.
Instead of dismissing the concept of reality or abandoning objectivity, we could ask ourselves: “How would this look from another perspective? How would this look one second before or after?”