Monday, 3 January 2011

Exercise 28 - Measuring Exposure Part 1

First post of the new year so Happy New Year everyone. I'd like to get TOAP and DPP completed in 2011 and I'd also like to have made a decision about what subject I'm going to use for my next RPS qualification, the ARPS.

But before all that I need to complete the colours assignment for this course. I'm waiting for some colourful items to be delivered by post, so in the meantime I have started reading the next part of the course which is lighting.

I'm a big fan of using light in my photography and I really like the work of David Hobby and the strobist movement. So this will be an interest section for me. I've flicked ahead and read through the assignment for the light part and my brain is buzzing as to which object I should use. I am very tempted to use on of the cats!

The first part of the first exercise is to show an understanding of how camera sensors (not film in my case) measure light and how they can sometimes get it wrong with just an average reading.

 In this first image the camera sensor has produced an average reading which puts the exposure at such a setting that the cat and the immediate area around it is exposed correctly.
The stronger light coming from the sky light is completely burnt out as they recommended settings are too bright for any detail to be picked out.
Aperture F4
Shutter Speed 1/40 sec

 When the exposure settings are changed, the skylight can be shown in much more detail so that the clouds and the blue sky are seen.
This second picture was still at F4 but the shutter speed was changed to 1/2000 of a second to show how much less light was being allowed onto the sensor in order to show the sky detail.
The two images above show an important point but its difficult to see the purpose as there is nothing in the sky.
After the other cat had successfully removed the first from its perch to see what was so interesting I decided to take the photo from a lower angle to make a point.
Aperture F2
Shutter Speed 1/30

note: I had swapped to my compact camera at this point but it still allows for full manual controls
 When it came to taking the second picture, I increased the shutter speed to 1/800 second and the purpose was to capture a silhouette of the cat by exposing for the brighter light behind it.
 This image was taken opposite the home ground of Manchester United. A slightly boring picture (unless you're a fan I suppose). This is an exposure based on the average reading.
Aperture F8
Shutter Speed 1/160
 I decided to increase the drama of the picture and bring out some of the detail in the cloud. This meant darkening the image so I increased the shutter speed to 1/500 second and whilst some of the detail is lost, the drama is increased.

This image of a walkway in Salford Quays was averaged at F8 and 1/160 second.

I decided to make the walking man more of a focus by brightening the image so I increased the shutter speed to 1/30 second. 

No comments:

Post a Comment