WORK IN PROGRESS
It was a bright sunny day, not the ideal day to use a wide aperture. Some of the first photographs I took were well and truly over exposed due to the sun being behind me, and others were under exposed due to being in shadow, as in the images below. The camera was set to aperture priority, and centre focus, ISO was set at 100. Eventually I got it right.
Getting the balance between aperture and shutter speed is all important as this goes a long way to getting the image you want. I wanted a shallow DoF, which meant that the wider the aperture, the better chance of getting the image I was after. But as I say, it was a really bright sunny day. Opening the aperture meant that I was going to let a lot of light in. There for I had to compensate with the shutter speed to make sure that the shutter was only open for a short time. Thinking about the environment, weather and position you are in, will need to be addressed if you are going to get the right exposure for the image you want to create.
If we think of the aperture and shutter are like a see-saw, increase one, and decrease the other. The higher number of the f stop ( equals smaller aperture ie f/32) dictates more time (shutter speed) is needed to allow the light in. One the other hand, the lower the number of the f stop (equals larger aperture ie f/1) has more light, therefore less time (Shutter speed) is needed to allow little light in. The diagram below gives an indication of the settings required for specific scenarios.
The images below have not been processed and are as taken, with the exception of some cropping, where indicated.
This exercise is dealing with a combination of of wide apertures, long focal lengths and close viewpoints. I am to take a number of photographs, composing the out of focus parts with the main in focus subject.
F/5 1/800 sec ISO100 18mm Cropped
f/5 1/640 ISO100 18mm Cropped
f/5 1/1250sec ISO100 18mm Cropped
f/5 1/80sec ISO100 18mm Cropped
f/5 1/125sec ISO100 25mm Cropped
f/5 1/320sec ISO100 25mm
f/5 1/640sec ISO100 25mm
f/5 1/60 ISO100 25mm
f/5.6 1/1600sec ISO100 mm55
In the image above the shutter speed was 1/1600 this was a very quick exposure as not only did we have bright light, but the reflection from the glass and white table cloth would have an impact on the light sensor in the camera. Whereas the image immediately above of the tap, I was in the shade, so it was not so bright and the there were no white reflective areas, so the shutter speed was greatly increased to 1/60.
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