Sunsets and why we see the colors

To a photographer the sun is the most important source of light and color effects.

Every day the sun allows us to see our world by providing us with a clear white light. As the sun reaches noon (wherever we are) the sunlight appears at its purest and brightest. This is simply because at mid day it the light will have to penetrate the least depth of the earth's atmosphere.

At dawn and dust the sunlight has to penetrate the atmosphere almost horizontally, so the light has to pass through a greater volume of atmosphere. It is this greater distance that gives rise to the colorful effects we see on the sky, it is not caused by the sunlight it is the atmospheric conditions that produce the colorful effects.

Apart from weather conditions what causes the most of the colored effects are the particles suspended in the atmosphere. These particles cause various colors to appear in the sky, mainly at dawn and dusk.

The particles have various causes, the most common of which are

The Yellow Sunset

There as previously mentioned there are always particles in the atmosphere, as weather conditions vary the particle density also varies. A yellow tinted sunset is simply the sign of a higher concentration of particles, or a high density of atmospheric contamination. Scientifically speaking the filtering effect of atmosphere is increased allowing fewer of the wavelengths of light to be seen. It is the stronger red and yellow light wavelengths you are able to see in these conditions. These particles scatter and exclude the weaker violet and blue end of the spectrum.

The intensity of the sunset effects will vary depending upon of the density of this light the contamination. The yellows with tints of green, the golds and oranges this gives us are breathtaking.

http://www.panoramio.com/photo/118282332

The Blue Sunset

The opposite to the yellow sunset is the blue. The blue sunset is the sign of a low density of atmospheric contamination. Scientifically speaking the filtering effect of atmosphere is high reducing the wavelengths of light that can be seen by the viewer. The wavelengths you are able to see in these conditions are restricted to the blue end of the spectrum. This gives us some wonderful blues, reds and purple effects.

The intensity of the sunset effects will vary depending upon of the density of this light the contamination.

http://www.panoramio.com/photo/118494263

Why the Sky is Blue

Sky is clear Blue, simply because the light from the sun has to penetrate a thinner layer of atmosphere. So the wavelengths of light are subjected to much less particle filtering and so we get a nice blue sky, clouds permitting.

http://www.panoramio.com/photo/118282102

http://www.panoramio.com/photo/118282328

The wide diversity of effects we see are simply variations of the conditions above.

Haze

Haze is a term for local effects caused by particles in the atmosphere. Haze is caused by smoke or minute water droplets suspended in the air. Haze interferes with the visible light, and is most noticeable if viewed over a long distance. Haze is also an effect that is important enough to be mentioned in the BBC shipping forecast.

As photographers some control of haze can be reduced by the use of a haze filter, or polarizing filter. Haze however can be used to create a nice layered effect in landscape and seascape photographs.

http://www.panoramio.com/photo/119668109

If this is your description of your ability,
"I am only an occasional snapper of pictures - my sunsets are usually just a red dot in an uninspiring sky"*.
I hope the following tips will assist you in achieving better results. There are three ways that will help you improve your results.

How To Photograph A Sunset

The most important thing is know your camera, sounds obvious but be aware of what the camera's ability. The problem is intense bright light, which in turn creates of deep black.
First thing to remember expose for the bright areas. Why? Simple you can not recover over exposed areas there is no detail or colour left in the image.*.
The best lens to use is a medium telephoto, his will give you the best possible image of the sunset. Be careful especially SLR users you are effectively looking directly at the sun through a telescope. Dont use a very powerful lens.

Using Filters

Filters are a useful option, neutral density are the best, by way of explanation a neutral density filter is the equivalent of your sunglasses. It simply reduces the glare of the bright areas. Better still is a graduated neutral density filter, as it just covers a selected area above horizon.

A polarising filter is also extremely useful as it reduces excess glare. This filter requires some experimentation*. but it can be used in conjunction with a neutral density filter.

My preference is for the square acrylic filters as they are easier to use as they slide into a holder that fits into the filter thread of the lens. They are tough and they will last you for years, some of mine are over 20 years old.The holder easily transfers onto all your lenses. No filter thread no worries there are also holders that have a ring mount that will clamp on to the lens. The holders allow you to use 2 filters at once, very useful

Editing Your Sunset Photograph

This can be regarded a cheating by some and if over done it is very obvious. However a small tweak to get some detail in the darker areas of the photograph is quite acceptable. Just don't over do things it will show in the final image. The expense of photo manipulation software is not to high, but you probably already have on "MS" dose include a simple but excellent photo editor in the “photo” programme in the more recent versions of windows.
Remember DO NOT alter your original image you might regret it, save a copy.