Check the color photography is an art mastered only photographers can boast. From a physical point of view, but the color is so since the 20th century known. Starring in this brief explanation of physics: electromagnetic radiation, photons, wavelength and energy.

When the balance of charged particles is compared to an inertial observer, an observer measures the electric field. But if the charged particles moving in the same observer,In addition to the electric field is another area that has been observed, the magnetic field, which appointed. These two fields are used as a set of electromagnetic field. Energy is required to create an electromagnetic field. This energy is constant (for a static electromagnetic field, a field that does not change with time). If the field is independent of time, the electromagnetic energy of change over time. This led to a temporal change of the electromagnetic waves propagatingwith the speed of light. This wave carries energy from the electromagnetic field, and this energy is called electromagnetic radiation.

A photon is the quantum of electromagnetic energy, and is entirely determined by the frequency of the radiation from the mathematical definition of the report of the photon, is related to frequency and wavelength of electromagnetic report:
E = hf = hc / l
where E is the energy of the photon, "h" Planckconstant, "f" frequency, "c" the speed of light, and "L" on the wavelength. There is a one-to-one relationship between energy, frequency and wavelength.

electromagnetic radiation of different wavelengths (or energy or frequency) have different names. For example, if the wavelength is greater than 0.1 meters, the influence of "high frequency", where between one millimeter and one micron is called "infrared", between 0.1 micron and nanometer equivalent to "Ultra Violet", the one betweenNanometers and 0.1 angstrom X-ray, and finally, when more than 0.1 Angstrom gamma rays.

As we all know, photography is concerned about the visible electromagnetic radiation (light). This is a very narrow range of wavelengths, ie 4000-8000 Angstrom. Our eyes are able to demonstrate that electromagnetic radiation in this region, and perceive different wavelengths of different colors. For example, let the electromagnetic radiation at 8000 nm, such as red, 5600yellow in 5000 as green, blue, like the 4500 and 4000 as violet. Black and white are not colors: black is the absence of light, all white, along the overlay of all colors.

All things in our world is rarely emit or reflect light in a wavelength. They are generally aware that a range of frequencies. The curve of energy distribution, ie the light energy reflected or emitted by the wavelength, you can have any desired shape. A well-known curvesuch is the influence of the cavity. If the object we seek a distribution curve of energy, with a maximum given in a certain wavelength, we will probably see this object is the color, wavelength. For example, our sun shines throughout the visible spectrum, but has a maximum corresponding to the wavelength of yellow, which is why we see yellow. It depends on how our eyes react to light.

Here's another example. An object can have twoMaxima in the distribution of energy. This occurs, for example, if we take a little 'color on white paper and blue and yellow. We'll see if green. It is not surprising. In fact, looking at longer wavelengths: green is halfway between yellow and blue. But once again, a physical point of view, a real green with its single wavelength has nothing to do with two maxima centered on white and yellow. This is our interpretation of the vision system.

Thus,Colors of nature and the struggle to save our customers on how our eyes see, the electromagnetic radiation with different wavelengths.

There are so many camera models on the market today. How can you begin to buy, decide? Here are some steps and guidelines for the purchase of a digital camera.

First, determine which of the three categories of camera you need:

1. Compact point and shoot. These cameras are usually the 8 megapixel (MP) range and image stabilization, Face Detection and slow small. They are more suitable for casual users, becausetake small, easy to use, and generally stable. Are not as many features and functions such as larger or more advanced cameras. Some of these cameras are waterproof and / or waterproof. If you buy an external person, ask to look for these functions. Cameras in this category typically retail for $ 150-250.

2. Advanced point and shoot. Even prosumer cameras, these devices often resemble a little larger reflex 'reduced the body and interchangeable lens. Often not, with large areas of built-in zoom (10x to 15x are uncommon). Cameras in this area run from $ 250 to over $ 500 if you're in a prosumer more than $ 400, you think moving to a digital SLR (DSLR). The discount is available to the public, except for the cost of a digital SLR is compatible with the lack of lens interchangeability in context.

3. Digital SLR. These cameras feature interchangeable lenses and usually the best sensorand software. Although not so small, that can be used in both automatic and manual modes, and you have a high level of creativity available. Digital SLR price and functionality has never been better. Ans The initial $ 500 – $ 600 cameras are great, and $ 700 – $ 1,500 mid-range cameras are incredible, with features that would be 2 or 3 has the camera cost $ 3000 or more. This is a highly competitive market. Nikon and Canon are trading blows in many models … whileSony has jumped time their price, performance and capacity in line of Alpha, which comes from the old design Minolta.

Now you have your camera to the selected category. Below you will find detailed instructions on how to choose a camera in one of the categories above.

The election of a slimline point-and-Shoot

Basic requirements – 3x optical zoom or better. Image Stabilization. Face Detection. 8 megapixels or more.

Special Features – The video modeWaterproof. But this will require, if you need to work. New this year is "Smile Shutter", which should take pictures when your subject smiles. I have not tried this … sounds fake to me.

Things to ignore – wireless digital zoom. Most wireless is not the "wireless", used by a laptop computer. Look for this to be really popular next year.

Recommendations – There are over 150 models available. Choose a color, the producer and the price you like. Expect to spend$ 150 to $ 250 Cameras under $ 100 are probably the old models, but may also work for your situation. Taking an old model that can be 6 megapixels or more is a lot.

The choice of a point and shoot prosumer

Basic Requirements – 10 or more megapixels, 10x optical zoom, image stabilizer.

Special Features – Some video output mode and in high definition on an HDTV.

To ignore things – digital zoom.

Recommendations – Kodak 15xZoom equipment up to 10 megapixels for less than $ 300. Canon zoom 10-in 9MP, a model for under $ 250. Olympus has a waterproof 8-megapixel model for under $ 250.

Choosing a DSLR

Basic Requirements – 10 or more megapixels, Live View (for the models published in 2008). All brands are a good comprehensive manual and automatic.

Special features – high-speed shutter, metal panels, stabilization system of the camera (Sony / Alpha), High ISO shots (betterPictures in the dark – under the leadership of Canon at this point), dust and weather resistant organisms.

Ignore the facts – in a sense, ignoring the millions of pixels. 10 or more is good in these times. If you're not going to do a routine 16 "x20" or expansions, not hung up on megapixels.

Recommendations

Best Entry Level DSLR:

– Sony Alpha A300 kit. 10.2Megapixels in stabilizing the camera. With a slow start, surprising $ 599. Wow The only problem is the compatibility of the lens. If youNo Canon or Nikon "glass", is done to them. In stabilizing the camera is amazing. I toured with him for the old Minolta prosumer and function is excellent, from 2 stations of the hand shooting skills.

– Kit Canon Digital Rebel XSi. 12.2 MP with lenses for $ 749 startup.

– Nikon D60 Starter Kit 10.2MP with $ 649 target.

Best Mid Level DSLR:

– Sony A350X 14.2Mp (WoW), image stabilizer and the kit lens for $ 799.

– Nikon D90 12.3MP, HDMovie function! While a kit for $ 1299 this murderess said the picture quality poor light.

– Canon 50D 15.1 (yeah!) $ 1599

In addition to these are at the top SLR is probably not so much to give as a gift for serious amateur or professional to buy their own, so I'm not going here.

Resources

The best place for digital cameras Review (dpreview.com). Your camera reviews highlight the strengthsand weaknesses of each model, and often are compared with their counterparts in the same category. If you spend up to $ 500 or more on a digital camera, do some 'research around. If you're ready to buy, check, visit your local photo shop. They may not be able to beat the weaker electronics store or website, but their service and support, especially for first time DSLR owners to pay the additional costs. Addition, it maintains a store near youlife.

To consider additional items for purchase

I would not leave the house without a good monopod for my SLR. Also consider the memory cards and extra batteries. A good camera bag with space for additional lenses were estimated by enthusiasts SLR. As a UV filter / protection and polarization are also good – make sure you know the size of the lens. It may be advisable to wait for additional lenses, or call the person a greeting card to Amazon, Beach Camera, camera shop or premises, so thatis possible with the camera and their needs before they are used the more expensive lenses.

I hope you have a good idea of what to look for when choosing a digital camera for Christmas. Good hunting!

I am by your inaction or lack of will of others is disabled? If yes, in photography, at least you're not good opportunities.

Sometimes it pays to be persistent. How many times you get into a great occasion, only to have obstructed, or their own inhibitions or the other. Many times photo opportunity is lost because the photographer is not able to find the courage to ask permission of the photo. Maybereception has been lost because they were discovered.

And 'certainly unpleasant, but the bull by the horns and STEELING you, you can learn to feel more at ease in these situations.

Asking someone if you can make your recording, often with a "Yes, yes, and a large photo below, you can share with the subject. In other cases, a polite" is not "the answer, thank you, this case, move the person and politelyon.

Access to land for photography can be an obstacle. But if you see an image potentially important in the production, turning to ask what is the problem with the knock on the door of a residence of someone? If you explain why you want to do and to provide the images that you feel more comfortable to share. Again, a negative answer may simply be disregarded before using.

Perpetuate.

Microelectronic image sensors used in digital cameras such as CCD and CMOS generation of electrons authorization of photons to detect the incident light. We want to give a deeper insight into the physics of this phenomenon.

Photons rec Collide Image Sensor

Provided that the incident photons can break the covalent bonds holding electrons on atomic sites of the network, as the photon energy is sufficient. This is what happens when you press the shutter buttonour camera. The light from the scene that we shot hits the image sensor. Image sensors are made of silicon, like other integrated circuits. Once the covalent bond has been broken, the electrons freed in a position to move in semi-conductors. This process is called "Photo-generation." As for the band structure energy, which corresponds to electrons excited from the valence band to the conduction band.

Sensors respond to infrared radiation

ForPhoton to be able to do so, he must have power equal to or greater than the bandgap energy is the energy between the valence band and conduction. The Gap Band in silicon with no applied voltage and temperature is 1.124eV. This is the most visible part of the electromagnetic spectrum at a wavelength of 1.10 microns. So now we know that digital camera sensors are sensitive to infrared radiation. As a photographerusually do not want to enter into this part of the spectrum, a goal it is necessary to filter the infrared rays before the light reaches the sensor. All cameras are equipped with such filters. Digital cameras allow infrared photography, but have the ability to remove the internal filter.

Absorption coefficient

The incident radiation is absorbed on the surface of semiconductors as it enters the crystal lattice. The equation that describes this processis

I (x) = I exp (-ax)

where "I" is the energy that reaches the surface of the semiconductor (sensor), "x" is the depth in the semiconductor and "a" is a coefficient, the coefficient of absorption. "Since the exponential always says, the absorption is very strong, so that the photons are easily absorbed, as the sensor on. Absorption coefficient is a strongly decreasing function of the wavelength of photons. To give a magnitude, high-energy UV –Radiation penetrates about 10 nm in silicon before dissipating significantly, while the infrared light of about 100 microns, or 10,000 times smaller. The absorption of photons with energy above The Gap Band almost exclusively on the production of electrons.

The obvious difference between the image sensors SLR D90 and Canon Rebel T1i is 15.1megapixels and 12.3MP respectively. With these data and the application may think a little ', many people lead to the conclusion that the transaction Rebel T1i probably better.

Unfortunately, data on exceeding customer radar, which is simply not correct. There are better image sensors (Canon 40D SLR), which are used in planningStage.

I'm sure you've learned in some of my other discussions, such as megapixels are not necessarily the most spectacular shots. The image sensor must be designed to cope with more megapixels.

The sensor of APS-C of Rebel SLR T1i that is used is actually a little 'smaller than the DX-type image sensor with Nikon D90 DX. Of course there are different approaches more pixels than a smaller sensor to achieve. With smaller pixels, timpani and closer than ever.What were talking about is in effect, a different measure of density of pixels. This is not a specific one can find many branded products for the packaging Canon Rebel T1i. Density of Canon Rebel T1i is 4.5 million pixels per square inch, but the D90 is 3.3 megapixels per square inch.

Crowded pixel is a nuisance, but there's more. How can you go in search of additional lenses, more megapixels means is provided which generally fall more money for betterPrice lenses. The goal is a work of high-megapixel digital SLR is designed for a higher resolution, and almost always charge.

Strangely, the objective, which is usually expressed's (EF-S 18-55mm f/3.5-5.6) from the manufacturer with the Canon Rebel T1i, not one that is good in the management of large appliances format megapixel resolution is appropriate. I know it is a bit 'more money, but the Canon 18-200mm AF-S would be a better target for T1i.

IfIt is not enough, you might be interested to know that the high pixel density may affect the performance of ISO, diffraction and dynamic. I do not know how to do it for you, but I'm beginning to believe that it is always less megapixel Nikon D90 12.3MP more money, better treatment for my bank account.

An old measure of image sensors RAW data is provided by DxOMark. DX-O-Mark has the Canon EOS 50D, which has experienced the image sensor is identical to that T1i and employssupports my hypothesis above, that the Nikon D90 produces better image quality. The Canon 50D test should test very close to the Canon Rebel DxOMark T1i once it is presented.