Nicola's learning log: Measuring Exposure

7th December 2012

In the following photographs I have used partial metering and exposure compensation to make the photos deliberately lighter or darker than average.

1/125 F13 ISO200 Focal Length 24mm Exposure Compensation -1

By setting the exposure to 1 stop less than the camera suggested, I was able to make the blue sky darker than it looked to contrast against the silver birch trunks and branches.

1/350 F13 ISO400 Focal Length 105mm Exposure Compensation -1

Some of this pond was still icy and there was a little contrast between the blues and browns. By altering the exposure, I was able to make the colours richer and have a more even exposure than I would have achieved using the camera's recommended meter reading. I used a high ISO as it was very windy which helped to stabilise the reeds as the shutter speed was faster.

F180 F13 ISO400 Focal Length 105mm Exposure Compensation -1

This composition requires 2 very different exposures to create what the eyes sees. Because of this I decided to concentrate on bringing out the yellow of the gorse which meant that I would loose the detail in the sky giving it a 'blown out' effect. Even though the exposure is -1 stop the sky is 'blown out' because the gorse is darker and therefore needs a longer exposure.

1/1000 F13 ISO400 Focal Length 40mm Exposure Compensation -2

This sign is made from a reflective metal, and when the sun shines onto it, it becomes difficult to see. When experimenting with this subject, I found that the faster the shutter speed, the more balanced the exposure was. Below 1/750sec, the photo became overexposed.

1/125 F6.3 ISO200 Focal Length 105mm Exposure Compensation +2/3

I took this seed head photo earlier in the year as an experiment with snow exposures. There is still room for improvement as the snow is blue in places. Having read around the subject a little, I need to be more confident and practice setting the exposure compensation at up to +2 and expose accordingly. I will also experiment with the white balance in future. I was pleased with the direction of light through the flower. It rim lights some of the feather like flower.

1/125 F6.3 ISO200 Focal Length 105mm Exposure Compensation +2/3

This thistle picture was an experiment with high key which I took earlier in the year. It has a blue colouring which would probably disappear if the exposure compensation was set at up to +2 and expose accordingly. I will also experiment with the white balance. The brown of the seed head is a focal point for the photo and the stem provides direction for the viewer.

For the following photos, I have used evaluative metering.

Savoy Cabbage

The central exposure is what I saw when I set this picture up. As the shadow falls on surface of the cabbage, it looks slightly too dark in the centre. I think the +1/2 Exposure Compensation gives a more even contrast of the cabbage and the background. I like the light being a little luminous at the bottom of the cabbage.

1 sec F8 ISO100 Focal Length 70mm 0.5 sec, F8 ISO 100 Focal Length 70mm Exposure Compensation +1 Exposure Compensation 0

0.7 sec, F8 ISO 100 Focal Length 70mm Exposure Compensation +1/2

0.3 sec/F8/ISO 100/FL 70mm 1/4 sec/F8/ISO 100/FL 70mm

Exposure Compensation -0.5 Exposure Compensation-1

Gingerbread Men

The central exposure was the scene in front of me. The camera set the same speed for the shutter on what it thought was the correct exposure and the –1/2 exposure compensation. The glitter and white piping on the –1/2 is less bright making the overall picture more evenly exposed.

1 sec F8 ISO100 96mm 0.7 sec F8 ISO100 96mm 0.5 sec F8 ISO100 96mm

Exposure Compensation +1 Exposure Compensation+1/2 Exposure Compensation 0

0.5 sec F8 ISO100 96mm Exposure Compensation -1/2

1/4 sec F8 ISO100 96mm Exposure Compensation -1

Pot Pourri

I noticed that the normal exposure was fairly bright. By stopping down –1/2 stop, the brightness was lost from the picture which allows more detail to be seen.

2 secs Exposure Compensation +1 1.5secs Exposure Compensation +1/2

F8 IS0100 Focal Length 58mm

0.7 secs F8 ISO100 Focal Length 58mm

Exposure Compensation –1/2

IMG_1304 crop altered to normal exposure compensation web

0.7secs Exposure Compensation 0 0.5secs ExposureCompensation –1

F8 ISO100 Focal Length58mm

Shiny flowerpot with black background

I thought this would challenge the camera to focus on three different subjects – shiny flowerpot, white bubbles and black background. I expected the bubbles and background to become grey with an incorrect exposure.I focused on the bubbles so that they would stay white with the correct exposure.The best exposure was +1/2.

1sec +1 Exposure Compensation 0.7secs +1/2 Exposure Compensation

F8 ISO100 Focal Length 88mm

0.7secs 0 Exposure Comp 0.3secs -1/2 Exposure Comp 1/4 sec Exposure Comp

F8 ISO100 Focal Length 88mm

Reflection of cooking utensils in saucepan lid

The normal exposure shows balanced shadows and contrast and colours. As the exposure time becomes shorter, the picture becomes too dark and shadow depth is increased. As the photo becomes overexposed, detail is lost. Normal and –1/2 are acceptable.

0.7secs Exposure Comp +1 0.7secs Exposure Comp+1/2 0.5sec Exposure Comp 0

F8 ISO100 Focal Length 105mm

0.3secs Exposure Compensation –1/2 1/4sec Exposure Comp -1

F8 ISO100 Focal Length 105mm

Tea set

The normal exposure is what I expected it to be. The exposure is still acceptable at –1/2 but by –1 the white shows the reflections and the painted detail loses definition.