You know it if you saw my episode on the subject, which I put above, but the depth of field is influenced by the aperture of the diaphragm, the focal length and the focusing distance. So, that remains true, but you have to know that if you have a tool that allows you to measure the depth of field by putting given values – by saying: I have a Full Frame sensor, I’m at f/16, 40 mm and 1 meter from my subject, and it gives you X in depth of field – you have to know that the value that you are given remains an approximation.
So, I’m not going to go into the technique, because it’s the opposite of the idea of this video, but basically, to make these calculations, we need a value called the circle of confusion.
The problem is that this circle of confusion is bound to remain subjective, because it depends on a lot of parameters that we don’t completely control, and in particular the visual acuity of the viewer.
In short, without going any further because I don’t want to dig into this subject, it is not at all the goal of today, you just have to remember that the mathematical value of depth of field that we can give you, it remains an APPROXIMATION.
Moreover, there is a second thing to know, it is that the depth of field, it is not distributed in an equal way around the place where you made the focus. So, if I focus on my eye and the depth of field is 10 cm, well, you won’t see 5 cm in front and 5 cm behind. That’s not how it works.
In general, the approximation we give is that there is about 1/3 of the depth of field in front and 2/3 behind, even if it seems that in macro it is not exactly the case, so, in fact, it remains an approximation. You can’t know it very accurately because, as I said before, there are approximations even before that.
So, if I remind you of all this, it’s not to be technical, on the contrary, it’s just to remind you that in real photography, in practice, where you have a camera in your hand, not a calculator, it’s just impossible to control the depth of field exactly, to know exactly how it will be, how deep it will be, what it will look like.
There’s an element of vagueness
And that’s exactly what makes it beautiful. You have to assess visually what is interesting for you, what you want to do, but not mathematically. There’s no point in doing calculations, you’re not going to, on the ground, start taking a tape measure, that’s not how it works.
Entry Frequency: one-time
Facebook required: no
Twitter required: no