Wednesday, 30 September 2015

One for the money...

What's this blog about?

I've just enrolled on the BA 3D Computer Animation course at Swansea College of Art (UWTSD). The first year includes a module called Performance & Audio/Visual Techniques and requires this blog as a record of our investigations and thoughts around the subject.

Having received some initial input, an introduction to the module from Dave Morgan this morning, I wanted to get this blog going with some of the subjects he covered.

Don't quote me, I'm investigating!

Cameras: The very basics (in no particular order)

In order to build an understanding of the use of virtual cameras in 3D applications (such as Maya), we need a foundation in the physical world.

First up; That tricky f-stop

The aperture is the opening of the lens that allows light to enter and be captured either on film or (for our purpose) by the camera's digital sensor. The larger the opening the more light is allowed through. The f-number (or f-stop) is derived from the ratio of the lens's focal length to the diameter of the aperture. The f-stop is inversely proportional to the aperture size so...

smaller f-stop value, larger aperture, more light...

larger f-stop value, smaller aperture, less light...

Got it?


Image from: http://photounleashed.com/wp-content/uploads/2015/05/Photography.pdf

So what does that do for the images we manage to capture?

This really hairy guy makes good use of a Kermit model to demonstrate the effect of varying the lens's f-stop value.


The effect can also be seen in this series of images:
Image from: https://jchan1996.files.wordpress.com/2010/04/50mm_f1.jpg

Q. What is the effect? A. A variation in the depth of field

The smaller the f-stop value, the shorter the depth of field

The larger the f-stop value, the longer the depth of field.

Q. What is this depth of field thing?
Q. If less light is allowed through a small aperture, aren't my photos going to be darker?

Good questions. I shall investigate further.... next time....

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