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5. Natural light – Project 39, Using Faster film & higher sensitivity (III)

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Higher sensitivity helps a lot when we consider shutter-speed and its effect on subject/camera movement. The price that has to be paid for this “stability” is Digital Noise (what used to be “grain” when using film).
These two images are sections of the previous ones, one shot at ISO100 and one at ISO400. The faster setting (ISO400), though in sharper focus, shows how much Noise is present.
This is actually only important when printing at larger formats. The subject may also be that important that a little “Grain” becomes an irrelevance or we may even find it an attractive feature of the image.
27th Aug 2009, 21:53   comments (0)

5. Natural light – Project 38, Measuring the intensity of light

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5. Natural light

Light, whether natural or artificial, is the Raw Material of Photography. Without light we cannot produce an image, it is the essence of photography. Fast films (with a high ISO) will record an image with less light. Also, the “quality” of light is important. Time of day, season within the year, will affect how a scene appears. We need to be able to recognise and choose our light and be able to control it. Knowing why a scene looks attractive enables us to go out and find similar scenes with similar (attractive) light conditions.
The intensity of light.
Brightness varies throughout the day. When the sun is low in the sky it must pass through thicker layers of atmosphere than when it is high in the sky. Our eyes adapt easily to these changes, cameras less so.
We can measure the brightness of the light at any given time of day using our camera’s light meter. ISO is a system for indicating how sensitive a particular film is to light. Digital cameras have, of course, no film and the ISO system has been adopted, for reasons of continuity, to indicate changes in a sensor’s sensitivity to light.

5. Natural light – Project 38, Measuring the intensity of light

This project aims to familiarise us with the kinds of brightness one can expect at different times of the day.
With the camera set to ISO100 and 1/125th sec exposure (for consistency) I took a number of readings throughout the day, from 7am to 6pm. Pointing the camera at a piece of neutral grey foam card I adjusted the aperture to give a “correct” exposure each & every hour of the day, in full sunshine, recording the changing f/stop readings along the way.

As we can see in the graph, the light intensity does not go on increasing as the sun gets higher in the sky (as we might expect) but after about 40 degrees of inclination light levels remain fairly constant until the same 40 degrees are reached in decent.
These readings were taken in mid-summer (August in NL). I would expect the curve to be similar in winter, though shorter due to there being less hours of daylight, and the light would be less intense at its highest levels so a larger aperture would be needed than the f/16 recorded here.

Indoors the light levels were much lower.
27th Aug 2009, 10:58   comments (5)

Assignment 2, Colour (I)

16 images (plus 16 diagrams)

This assignment required four (each) examples of;
“Colour Accents” (a dab of colour that stands “alone”)
“Contrasting Colours” (colours positioned at one third distance around the colour wheel)
“Harmonious Complementary Colours” (Colours that sit opposite each other on the wheel)
“Harmonious Similar Colours” (Colours that find themselves adjacent to each other)
________________________________________
Colour Accent #1

Nikon D80, 18-135mm lens fitted (with circular polariser)
f/5.6
1/500th
ISO-100
Minus 1 stop exposure bias

This image of rows of red tulips contains just one “lost” yellow example which I thought stands out rather well as a colour accent.
________________________________________

Colour Accent #2

Nikon D80, 18-135mm lens fitted (with circular polariser)
f/5.6
1/30th
ISO-500

The colour of this paint is very typically Dutch (my front door is painted in this shade of green) The brass door handle stands out nicely against the expanse of green.
________________________________________

Colour Accent #3

Nikon D80, 18-135mm lens fitted (with circular polariser)
f/3.3
1/1000th
ISO-200

Oxford is the town of the Punt (as well as Cambridge of course). All these unoccupied vessels are brown and drab, the blue interior of the one in the foreground, as well as the man’s shirt, jumps out of the frame.
________________________________________

Colour Accent #4

Nikon D80, 18-135mm lens fitted (with circular polariser)
f/3.5
1/500th
ISO-200

A red British post-box stands out nicely against a dull grey stone wall as a splash of colour in the greyness (however nice the texture of the stone might be).
14th Aug 2009, 19:52   comments (5)

Assignment2, Colour (II)

Contrasting Colours #1

Nikon D80, 70/300mm lens fitted (with circular polariser)
f/4.5
1/90th
ISO-800
Minus 0.5 stop exposure bias

The blue and yellow of the Dutch NS railways are a good example of two contrasting colours. Blue and yellow are at “thirds” around the colour Wheel. I waited until the cyclist was in shot before releasing the shutter. I liked the kind of “frame” the roof, pillars and platform provide.
________________________________________

Contrasting Colours #2

Nikon D80, 10/20mm lens fitted (with circular polariser)
f/4
1/350th
ISO-200
Minus 0.5 stop exposure bias

The (faded) red & blue of the Castle Barge, Newark, are a third of the way around the colour wheel, making them a contrasting pair. The colours in the Barge’s reflection in the water are stronger, richer.
________________________________________

Contrasting Colours #3

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/5.6
1/125th
ISO-400
Minus 0.5 stop exposure bias

This Carnival image contains three contrasting colours, Red, Yellow & Blue, which are all at “thirds” on the wheel.
________________________________________

Contrasting Colours #4

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/3.5
1/10th
ISO-800

The gorgeous colours, textures & shapes of the Lowry centre, Salford keys, fascinates me. I keep going back. This purple/orange combination is an eye-catching contrast.
14th Aug 2009, 19:47   comments (2)

Assignment 2, Colour (III)

Harmonious – Complementary Colours #1

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/5.6
1/500th
ISO-800

This violet & yellow combination in what was a sea of these flowers is an example of two complementary colours, violet & yellow being opposite each other on the colour wheel.
________________________________________

Harmonious – Complementary Colours #2

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/8
1/640th
ISO-200
Minus 1.7 stop exposure bias

The green sprinkling of chives on these orange prawn sushi (or is it “sashimi”?) make a good complementary combination, orange & green being opposites on the colour wheel. The lighting is simply from the sun through the kitchen window.
________________________________________

Harmonious – Complementary Colours #3

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/6.7
1/125th
ISO-100

Red & Green are two complementary colours, this field of red tulips and their green leaves are very much complementary to one another.
________________________________________

Harmonious – Complementary Colours #4

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/5.6
1/45th
ISO-800

The evening sun gives this stainless steel structure (the Imperial War Museum of the North) an orange/yellow glow which complements nicely the darkening blue of the sky behind it.
14th Aug 2009, 19:43   comments (0)

Assignment 2, Colour (IV)

Harmonious – Similar Colours #1

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/3.3
1/750th
ISO-100

This “downpour” of yellow flowers in between the shades of green of the tree’s leaves gives a lovely harmonious effect as these shades are adjacent on the colour wheel.
________________________________________

Harmonious – Similar Colours #2

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/5.6
1/30th
ISO-200

From green, via yellow, through to orange, this sunflower and its leaves contains colours that are all adjacent to each other on the colour wheel.
________________________________________

Harmonious – Similar Colours #3

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/5.3
1/60th
ISO-200

The yellow and the green in this image of a wilting sunflower are adjacent on the colour wheel and therefore similar colours.
________________________________________

Harmonious – Similar Colours #4

Nikon D80, 18/135mm lens fitted (with circular polariser)
f/3.5
1/2000th
ISO-800

The various shades of yellow and the shades of green here are all neighbours on the colour wheel, making them “similar”.
14th Aug 2009, 19:09   comments (0)

4. Colour - Project 37, Filters with Black-and-White film

Strongly coloured filters will change the tonal relationships in a black & white photograph. They allow certain wavelengths to pass but block others.
Setting up a still-life containing the same three colours as the three filters (yellow mustard jar, Red rose, blue dish) as well as a piece of grey card for reference I took four photographs. One without filters, one with the yellow filter fitted before the lens, one with the red filter and one with the blue.
The resulting images were converted to black & white and are seen here.
It is clear to see that each filter lightens the object of the same colour and darkens the others, especially its complimentary colour.
9th Aug 2009, 14:44   | tags:,,comments (0)

4. Colour – Project 36. Warm & Cool colours

The strongest division on the circle is between the Warm and the Cool colours.

In P 32 & 33 I produced images of Primary and Secondary colours. The warmer colours are the Reds & Oranges, the Warmest, in my opinion, being the orange of the indicator lens. The cooler colours are the Blues & Greens. The coolest, I think, is the blue.

Light too can be warmer or cooler, consider the difference between a “Warm” (red/orange) sunset scene and the much “cooler” feel to subjects in shade under a crisp, blue sky.

In addition to the “Coolest” and the “Warmest” choices from P32 & P33 I have here one image that is a combination of Warm colours (the reds, oranges and yellows of the Dutch tulip fields).

One image that is a combination of Cool colours (the blue Iris and its green leaves).

The next three are combinations of Warm & Cool colours in the one image;

The orangey-red (warm) sunset against the dark blue (cool) evening sky at the Angel of the North.

The wonderful blue (cool) & red (warm) display colouring on the Turkey’s head and neck.

The sprinkling of green (cool) chives on the orange (warm) salmon Sushi.
9th Aug 2009, 13:00   | tags:,,comments (1)