Category Archives: 02a- Focus at different apertures

Focus at different apertures

This exercise aims to demonstrate the way that aperture can affect the focus in a shot. For this exercise I chose to photograph coloured pencils from a very low angle. I set the camera on a tripod and focused on the orange pencil in the centre of the image.

18mm, F3.5, ISO 800

I set the camera to Aperture priority, allowing the shutter speed to be automatically selected by the camera, and  took the first picture.  I set the lens to it’s widest available aperture, F3.5.

18mm, F11, ISO 800

I took the second photograph with the lens set to F11.

18mm, F22, ISO 800

The photograph was taken with a small aperture of F22.

I then printed the photographs and compared them. There was a noted difference in the limits of sharpness between each.

In image 1  the yellow, red and orange pencils are the only items which are sharp, with the pencils further back becoming increasingly blurred.

In photograph 2 the limits of sharpness become a little wider. The first 6 pencils are sharply focused with even the text printed on the navy blue pencil becoming clearer.

The third photograph has an even wider area of sharpness with more detail becoming noticeable such as the grain in the wood of the table and the text printed in the rear pencils.

I found the difference between these 3 images quite remarkable. I personally liked photograph 1 the most. I liked the blurring of the pencils and colours at the end of the row as it conveyed a sense of distance.