During Bai’s birthday lunch. I pestered him about fiddling the DoF on my AV-1. Turns out, there was no Depth of Field preview for it. All I can hope for is twiddle with the aperture and hope for good results. Nyaha.
Anyway here’s the full blown, nose-bleeding, formula-counting terminologies @Wikipedia, but as always a sort excerpt for the photog33ks :)
In optics, particularly film and photography, the depth of field (DOF) is the distance in front of and beyond the subject that appears to be in focus.
//insert really, REALLY long explanation about
I tried reading…the keyword is tried and tried to understand before posting anything relevant in fact I have some crazy examples on how lame I am on the aspect of DOFs. :D
Bai explained how DOFs depend on the aperture and the lens. The higher the aperture (meaning smaller the number), the smaller the DOF is. So most probably, I shouldn’t be using a f/1.8 if there are 3 people in the scene…like so…
roovin’s the only one focused here. haha.
I am guessing I’m using a f/1.8 or a 2.8 here. I focused Roovin on the center, and left harmy and helen to sort of blur in the background. To correct this, I should’ve used a lower aperture like a 5.6 as suggested by Bai when shooting groups.
With regards to lens (and I cannot really tell on my own since I only have my kit lens here with me) effect, I remember one example. For shooting insects on a macro lens, you have to lower the aperture to around 16-22, or your bug’s eyes will be the only clear thing you’re seeing.
some other formal explanation from the Wikipedia site earlier.
The image format size also will affect the depth of field. The larger the format size, the longer a lens will need to be to capture the same framing as a smaller format. In motion pictures, for example, a frame with a 12 degree horizontal field of view will require a 50 mm lens on 16 mm film, a 100 mm lens on 35 mm film, and a 250 mm lens on 65 mm film. Conversely, using the same focal length lens with each of these formats will yield a progressively wider image as the film format gets larger: a 50 mm lens has a horizontal field of view of 12 degrees on 16 mm film, 23.6 degrees on 35 mm film, and 55.6 degrees on 65 mm film. What this all means is that because the larger formats require longer lenses than the smaller ones, they will accordingly have a smaller depth of field. Therefore, compensations in exposure, framing, or subject distance need to be made in order to make one format look like it was filmed in another format.
I basically understood about that on most part. What really got me was the Camera Movements and the DOF as well as the…come again..Scheimpflug principle…oh boys…let’s read on shall we?
Normally, the lens and image (film or sensor) planes of a camera are parallel, and the plane of focus (PoF) is parallel to the lens and image planes. If a planar subject (such as the side of a building) is also parallel to the image plane, it can coincide with the PoF, and the entire subject can be rendered sharply. If the subject plane is not parallel to the image plane, it will be in focus only along a line where it intersects the PoF, as illustrated in Figure 1.
Figure 1. With a normal camera, when the subject is not parallel to the image plane, only a smallregion is in focus.
I was reading that part over and over again (even tried gazing once or twice at the diagrams and got a nosebleed). I have an example that’s quite like Figure 1 over there,which is this one.
looks the same!
Will continue on this tomorrow…my brain is spinning *laughs
note: I continued on hyperfocal distance at the next entry :D
