Understanding wide open apertures #photography

When we take a photograph the shutter snaps open and closed. The aperture is how wide that doorway to our camera opens.

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Imagine the shutter as a doorway, the stops go behind the door and so a large stop say F/16 only allows the door to open a little. At f/30 and we have a tiny pinhole and at f/3.5, on most lenses, it wide open. On my 35 mm prime lens, wide open is even wider at f/1.8.

Wide open

This is Libby and I shot this picture wide open at f/1.8 and used the light from the window to backlight her hair. The depth of field is shallow and so the view outside the window is blurred and the bottom of the image isn’t as focused on Libby’s face. My focus point was exactly between her eyes. Next time I’ll focus on her right eye and use a reflector to put more natural light on the left of the frame.

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Bokeh

Bokeh is that blur in the background and you can see now that have taken a shot closer that the pattern on the seating to the left is blurred and so is the window. The depth of field is shallower. You have to be careful not to make it too shallow.

Smartphone cameras

I’ve recently bought a new LG G5 smartphone and so at the weekend, I tried out the camera. It was set on manual and so I naturally set the ISO, white balance and shutter speed, as you do. That was time-consuming and so I switched to auto and it didn’t take great pictures. I’m not used to smartphone cameras and so I took another look at it today. Then I realised they always shoot wide open. You can’t change the aperture, which means they are great for selfies and close up shots like this one, but for landscapes, you really need a narrow aperture. So no, smartphone cameras are not as versatile and hence not as good as a camera, especially a DSLR which has a larger sensor.

Looking at both of out pictures today, there is a softness to them. That is partly the light and partly the lens. The images are quite sharp and you can see individual hairs but next time I would like to get eye colour and that requires light reflected at the eyes.

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