Part 2 Exercise 2.7

For this exercise, to explore maximum depth of field I have chosen two sequences, one indoor and one out.  In each case the series were taken with a 10-18mm wide angle lens, set to 10mm focal length.  The camera was mounted on a tripod to achieve consistency of view, and to avoid shake as ISO was 100 and some of the exposures were relatively slow.  For both the camera was set to Aperture Priority and for the purposes of comparison the apertures were set to variously f/22, f/20, and f/18.

A couple of things strike me.  One is that without close inspection it is not startlingly obvious how the depth of field changes between the different apertures, although the difference is clearly there.  The images that feel more inclusive are, for me at least, clearly those taken at f/22 – the greater depth of field gives a greater sense of immersion and inclusion in the view.

The other is the amount of distortion that is evident in the interior shots, much more so than those taken outside.  The square tiles on the floor have become lozenges!  This effect is perhaps more noticeable in this sequence because of the strong geometric lines formed by the tiles and the structure of the space generally.

From a compositional point of view I prefer the exterior shots: the shadows on the right counter-balance the bright rendering of the cottages to the left; the road and the overhead telephone lines draw you into the scene more effectively; and the depth of the scene is not truncated in the same way as the interior shots by the far wall at the end of the room.  I think it also helps that with the exterior shots there is a stronger visual element on the left hand edge of the picture that is close to the viewpoint, anchoring the image more successfully.  For some reason the structure of the room does not seem to work in quite the same way for the interior sequence and the exposed stonework on the right is a little too far away to serve a similar function.

. IMG_4232copy

f/22, 1/40sIMG_4233copy

f/20, 1/50sIMG_4234copy

f/18, 1/60s

f/22, 100s

f/20, 1/125s

Since originally posting this I have decided that just two exterior images are not enough and that only two different f-stops does not do this issue justice.  I have therefore now added the following additional sequence, ranging from f/22 to f/16.  All taken at 10mm focal length, ISO 100, Aperture Priority.

f/22, 1/20s

f/20, 1/25s

f/18, 1/32s

f/16, 1/40s

This longer sequence gives a clearer indication of how shutter speed changes with aperture.  It is though again difficult to see easily how the depth of field has been affected.  I suspect that to see significant differences it would be necessary to go up to higher f-stops than f/22 but none of my current lenses appear to be able to go beyond that limit.


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