Digital Slr Photography And You

Digital cameras have been around for a number of years. If the individual has a lot of fun using it, perhaps it is time to move up by investing in something better that is available in the market. Technology has paved the way for the creation of the digital SLR camera.

The SLR stands for single lens reflex. In fact, many photographers have decided to use this more often. This is because it gives the user more control in the look of the final product.

When the SLR first came out, this was sold at about $5,000 a piece. With the increasing demand in the market, manufacturers have came out with different models so the average person can buy one of these for less than a thousand. Those who want to do better with the more affordable version then will have to buy extra lenses.

The SLR stands out because of the lens used in the camera. This just proves that the piece of glass in this device really makes a difference when the pictures are developed. The user can change the lens to get a farther shot but this will really boil down to the contrast and color.

Another nice feature about the SLR is that it comes with controls allowing the owner to change certain things in the photo before it is downloaded and printed. This may be complicated for those who are not familiar with it so the user should get comfortable with the camera before using it.

Since the SLR is quite expensive, it will be a good idea to get proper insurance for it. This device fetches a good price in the market if someone should stumble into one which will really hurt anyone’s pocket should this be stolen.

There are many brands of SLR cameras in the market. All of these manufacturers have been in the business for quite some time, which makes it hard to recommend which one is the best to invest in.

Photographers and other hobbyists then should go with the brand that the individual is familiar with and use this to get those digital SLR shots. After all, this is the only way to use this piece of equipment and get the money’s worth out of this investment.

The owner should also know how to store and clean the SLR camera. It is only with proper maintenance and storage that excellent shots can be taken every time this is brought out.

A Holistic Approach To Buying A New Digital Camera

Many buy a new camera based on just a few parameters like purchase price and megapixels. This is unfortunate as there is much more to a new digital camera buying decision. This article will describe a holistic approach to that decision.

In the early days of the digital camera era buying a new camera was relatively an easy decision. Digital cameras did not have many options and checking simple things like price and the number of megapixels was enough. Since then however digital cameras have evolved and became more sophisticated. They have many new features and options. They can work with different accessories and use different technologies. Today when making a decision on a new digital camera a holistic approach that takes the different features and options into account is more suitable.

So what does it take to make a decision on a brand new digital camera? Following is a breakdown of what to check for when buying one. This list is not complete and you should use it as a guide to understanding the complexity of choosing a digital camera.

Cost: Do not confuse cost with purchase price. Purchase price is what you pay to buy the camera. Cost is the total money you need to spend including the purchase price in order to effectively use the camera. In most cases you will spend additional money on accessories and other additional products such as lenses, batteries, carrying cases and more. Failing to budget for those extra expenses can result in buying a camera just to find out it can not be effectively used without spending more.

User knowledge: It is important to buy a digital camera that is appropriate for its user’s photography level. If you are technology and photography savvy you can consider higher end cameras that allow more flexibility and manual options but are harder to use. Digital SLR cameras fall into that category. If you are not into photography or technology you might want to choose a camera that is easier to use such as a digital point a shoot one.

Expected usage: The digital camera you choose should be appropriate for its intended use. For example if you travel a lot for long periods of time you want to pay attention to features such as camera weight, size, battery life and memory storage. On the other hand if you hardly travel at all these features are less important.

Basic features: There are some basic features that are common to most if not all digital cameras. These features are:

Megapixels: you can not avoid the number of megapixels question. Is more megapixels better? It really depends. More megapixels is important if you are going to print photos and enlargements or if you are going to zoom in and crop photos. However if you plan to view the photos on your computer screen and occasionally print 4X6 copies then 2 or 3 megapixels is more than enough. Buying a digital camera with more megapixels is not a drawback but you should make sure that you could not have used the extra money spent on megapixels for other features that are more useful to you.

Batteries: Digital cameras use two kind of batteries disposable or rechargeable. Disposable batteries are easy to buy, carry and replace. They are available in any store and are very convenient when traveling. Disposable batteries however are more costly to use as you need to keep buying new batteries. Rechargeable batteries require only one purchase. However if they are empty during a photo shooting session or somewhere away from home or a power supply you can not just buy another battery. Take into account the cost of extra batteries based on the expected digital camera usage.

Zoom: There are two types of zoom – optical and digital. Optical zoom works by physically moving the camera’s lenses and changing the focal length. Digital zoom works by applying built-in software in the camera to define a portion of interest in the photo. Once chosen the software crops the rest of the photo and enlarges the area you chose. For quality and other reasons optical zoom is superior to digital zoom. From a practical point of view digital zoom should not be considered zoom at all. When you compare different digital cameras zoom figures always compare their optical zoom capabilities. You should ignore the digital zoom figures.

Accessories: Digital cameras can use a large number of accessories. You should be aware of what accessories are supported by your camera and which accessories you deem important to you. These should be taken into account in your buying decision. Some of the common accessories to consider:

Memory cards: Digital cameras store photos as files on a memory device usually a removable memory card. Most digital cameras are sold with a very small memory card. This lowers their purchase price. Such a small memory card can hold a small number of photos and is not practical. When buying a digital camera always check how much memory is included. Then assess how much memory you will need and check the prices of memory cards appropriate for you. Add this cost to the total cost of buying the new digital camera.

PC connectivity: Digital cameras connect to computers in order to download photos. The most common methods of connectivity are USB and plugging the camera’s memory card directly to the PC. Make sure that your camera includes the USB cable needed to connect to the PC. If you prefer connecting the removable memory directly to your PC budget an adaptor that can bridge between the memory card and the slots available in your PC.

Lenses: High-end digital cameras such as digital SLR often require additional lenses. When reviewing your camera check what lenses are included with the camera. If you need more lenses shop around for ones that fit your camera and budget their price. Lenses can be very expensive and can cost more than the camera itself. For example when buying an SLR camera for outdoor photography that requires zoom lenses make sure you budget such lenses that fit the camera you plan to buy.

External Flash: Most likely that you will not need to buy an external flash unit. If do need an external flash in addition to your camera’s built-in one make sure that you shop for one that can work with the camera and budget its cost before purchasing the camera. External flash units prices can vary and can be a costly addition.

Old Fashioned High Resolution Photo Camera

Tired of trying to keep updated with the highest mega pixel resolution digital camera? Well even if one has tried to do that, most certainly he will soon find out that his few months old digital camera is outdated in terms of mega pixel resolution. It’s an ever changing kind of product that has become very hard to keep updated, unless one is willing to spend more money by making purchases every six to twelve months.

If the main intention of purchasing a photo camera is enlarging the image, then mega pixel resolution indeed will become the main factor. In this case one might consider a different option, which will keep his product updated for years to come. I’m talking about a used 4x5" film photo camera, together with a high resolution flat bed film scanner. All of this for less than one thousand US dollars. With all of this, one will get over 100 mega pixels in fine detailed film resolution and fine scanned digital images that can be enlarged up to 30x40" in size with professional quality. These 4x5" film cameras have done a remarkable job in general personal and commercial photography such as wedding, portraiture, product, documentary, advertising and landscape for nearly a hundred years.

Where to find 4x5" used film cameras? Since some of these cameras were mostly used in the past, until the 1960’s, it should be no problem in finding them in American auction web sites. Anyway, a good used 4x5" camera with lens can be found for less than four hundred US dollars.

As for the flat bed film scanner, one can find brand new ones for less than five hundred US dollars. Just make sure the scanner is able to scan films.

Whenever purchasing a 4x5" film camera, one should look for the following features: folds into a compact box, flexible bellows, lenses that can be easily interchanged, accepts sheet film, ground glass focusing screen, easily handheld and optical viewfinder accessory.

As for the lenses, there are four main categories: 1 - general purposes; 2 - wide field (mostly used for close up work and landscape); 3 – extreme wide angles lenses; 4 – special effects lenses (telephoto). However, one might use a general purpose 127 or 152mm lens for most of his photograph sessions. In cases where it requires special lenses, such as architecture or macro photography, one will still find lots of them available in auction sites. Used lenses for 4x5” cameras made after world word II have excellent performances comparable to today’s modern lenses.

Whenever making a purchase of a 4x5" camera make sure that: 1 - the bellows have no light leaks, 2 – the lens shutter works accurate at all speeds; 4 – the lens elements have no fungus and scratches of any kind; 4 – the focus is working properly between the ground glass and the film.

The option of using a 4x5" film camera, together with a flat bed film scanner, for enlarging images with professional quality is viable and accessible. Cheaper than top digital cameras, the 4x5" film camera offers better image quality and will always be updated in the future, maintaining its original value.

For those who wishes the very most detailed image enlargement, one can always use the 8x10" film camera. Four times the physical film size of the 4x5", this option offers so much film resolution that it is considered by many as the ultimate step for photo image enlargement.

Sometimes analog products deliver better results that its digital counter parts. If you are doing the job of enlarging photo images, you should give it a try with a 4x5" camera. You might just surprise yourself.

Photogeneration – Physics Underlying Image Sensors

Microelectronic image sensors used in digital still cameras, such as CCD and CMOS, rely on electron generation by incoming photons to detect light. We want to give a deeper insight to the physics underlying this phenomenon.

Photons Collide against the Image Sensor

Incident photons can break the covalent bonds holding electrons at atomic sites in the lattice, provided that the photon energy is sufficient. This is what happens when we press the shutter release button of our camera. Light of the scene we are shooting strikes the image sensor. Image sensors are made of silicon, as all other integrated circuits. Once the covalent bond has been broken, the freed electron is able to move through the semiconductor crystal. This process is called "photogeneration". In terms of the energy-band structure, this is equivalent to exciting electrons from the valence band into the conduction band.

Sensors Are Sensitive to Infrared Radiation

For the incident photon to be able to do this, it must possess an energy equal or greater than the bandgap energy, that is the energy gap between the valence and the conduction bands. The band gap in silicon with no voltage applied and at ambient temperature is 1.124eV. This corresponds to the far infrared portion of the electromagnetic spectrum, at a wavelength of 1.10 microns. So now we know that sensors used in digital still cameras are sensitive to infrared radiation. As a photographer does not usually want to capture this part of the spectrum, a lens is necessary in order to filter out infrared radiation before the light reaches the sensor. All cameras are equipped with such a filter. Those digital cameras, permitting infrared photography, just have the option to internally remove the filter away.

Absorption Coefficient

The radiation incident on the semiconductor surface is absorbed as it penetrates into the crystal lattice. The equation describing this process is

I(x) = Io exp(-ax)

where "Io" is the energy reaching the surface of the semiconductor (the sensor), "x" is the depth in the semiconductor and "a" is a coefficient called "absorption coefficient". As the exponential expression always implies, the absorption is very strong, so that photons are readily absorbed as they enter into the sensor. The absorption coefficient is a strongly decreasing function of photon wavelength. As an order of magnitude, high-energy ultraviolet radiation penetrates about 10nm into silicon before decaying appreciably, while infrared light penetrates about 100 microns, i.e. 10000 times deeper. Absorption of photons with energies higher than the band gap is almost entirely due to the generation of electrons.

Tips For Buying Fine Art Posters

To be honest, I'm not an expert when it comes to interior design or home decorating. When you visit my home, you will see that I don't have the most expensive furniture, my fabrics and colors aren't coordinated, and I don't make the best use of space. You can be sure that you won't be seeing any pictures of my place in a "Better Homes & Garden" photo shoot in the future.

However, the case is different when it comes to my walls. In my opinion, there's nothing more depressing than a home with bare walls. As a result, I go out of my way to make sure that mine are covered with interesting things to look at. Some of my favorite wall hangings are the framed fine art posters that I've purchased over the years.

I would love to fill my home with original artwork, but I’m not wealthy enough to do that. Fortunately, I've found that I can add a touch of beauty to my home at a reasonable price through fine art posters. I can get everything from famous masterpieces by Da Vinci, Van Gogh, Picasso and lesser-known works by relatively obscure artists because there are literally thousands of fine art posters available.

Purchasing fine art posters from websites that specialize in them is the best way to obtain these posters. This is because you'll get a limited selection and higher prices if you try to buy your posters from a museum gift shop or from a regular store. You can save money through these websites because they often have special sales promotions.

You should buy frames for your posters so that they will look good when they're up on your walls. There are several framing options at your disposal. Websites that sell fine art posters often offer beautiful frames for their posters. Convenience is the advantage of buying pre-framed fine art posters. You'll be able to put the framed piece on the wall in just a few minutes once the package arrives at your home.

Buying the frame separately is a second framing option that you have for your fine art posters. This option is usually less expensive than buying pre-framed prints. However, you'll have to take precise measurements and then search high and low for a frame that is the perfect size, and complements the piece that you plan to showcase. I would not recommend buying frames for your posters separately because this is not as easy as it sounds, unless you have tons of time on your hands and like shopping.

Improve Your Photography With A Polarising Filter

A polarising filter is one of the handiest gadgets you can add to your kit bag, but before you rush out to grab one let's look at what they are and what they can do for us.

First of all, polarising filters come in two varieties, linear or circular. This refers to the way they are polarised, not their physical shape. If you are using an SLR camera the linear type can have detrimental effects on the metering and the auto-focus systems, so it's probably best to stick to the circular filters.

Assuming you are not using one of the filter systems such as the Cokin range, that have their own methods of attatching to the lens, you should bare the following in mind:

If you're using a compact camera that does not have through the lens viewing, look for a filter that has index marks on its rim. Without these it can be difficult to get accurate and consistent alignment.

With a wide angle lens a filter with a thick rim may cause vignetting by intruding into the edge of the field of view. Try to find one with a very narrow rim. Some are as thin as 3 - 4mm.

The rim will often be marked to confirm whether it is circular or linear polarised. Circulars are usually marked PL CIR whilst linear will only carry the PL mark.

You can check the quality of the filter before you buy. Look through it at a silver coin. A good filter will show the coin as black.

Check whether the rim is threaded on both sides. This will allow you to fit other filters on top of the polariser. If it is only threaded on one side, you will need to remove it to fit another filter directly to the lens, then mount the polariser on top of the other filter. As the polariser is likely to be on your lens a lot of the time, it's more convenient to be able to stack others onto it.

A wide range of filters are available from a number of manufacturers in sizes from around 25mm and upwards, so you should not have too much trouble finding one to fit your camera. However it is worth bearing in mind a point I have seen mentioned in some photography forums on the web. The general opinion seems to be that Japanese filters seem to suit Japanese lenses, whilst German filters work best on German lenses. The differences are unlikely to be critical, particularly as some Japanese cameras use German manufactured lenses, but it is something to bear in mind.

In the next article I will look at some of the ways a polarising filter can help improve your work.

A Common Photography Problem: Overexposed Digital Photos

Digital cameras are becoming more and more sophisticated. On one hand they allow high quality automatic point and shoot. On the other hand they allow full manual control of their settings. Regardless of the mode you use there are some scenes that require special care. Without such care your digital photos will be of poor quality regardless of how sophisticated and automatic your camera is.

New digital cameras include sophisticated hardware and software that allow a simple point a shoot usage and result in high quality digital photos. Such high quality digital photos are achieved in most scenarios but in some scenarios solely relying on the cameras automatic feature is not enough. In such scenes the camera hardware and software will make the wrong decision as to the optimal camera setting for the best digital photo. The result will be a poor quality photo.

Being aware of such scenarios can help in avoiding such poor quality digital photos. When you identify such a scenario you can use some simple techniques, by manually setting the camera, by changing the photo shooting angle or by manipulating the scene.

One of the common problems with automatic digital camera photo shooting is digital photos that are overexposed. Overexposed digital photos have blown out areas and sometimes are completely saturated and white. Their color is not rich and the objects tend to look white and not “alive”. The reason for overexposed photos is setting the exposure too low. Although the camera can measure ambient light and make the exposure decisions for you it can be confused by scenes that are more complex. Many times such scenes do not really have one perfect exposure setting and the best exposure depends on the results and the objects in the scene that you care about the most.

For example if there is a very bright light source in the photo it can confuse the camera to believe that there is enough light in the scene for a low exposure setting. The result will be a photo that captures the bright area but darkens all the others. Usually you can assume that scenes that have extreme lighting gaps between different areas confuse the camera – for example if a quarter of the photo is very bright and the rest is very dark the camera is likely to set the wrong exposure. When you identify such cases you can manually set the exposure to the right value for the results you are looking for. Another options is to pan the camera a bit and point to a scene that does not have such light gaps (for example that does not have a very bright object in it) but that its objects are in the same focus distance as the scene you are planning to shoot. At that point you can press the shutter half way down (or use any other specific camera mechanism) in order to lock the camera focus and exposure settings. Once you have done that you can pan the camera back to the original scene and shoot the photo.

The best way to learn how to avoid overexposed digital photos is by experimenting and practicing. Try to find scenes that will confuse the digital camera into taking overexposed digital photos. Take a few digital photos using the camera automatic mode and review the results confirming the expected poor quality. Now correct the problem and take a few more photos. Review the new digital photos and make sure that indeed the overexposed digital photos problem is gone. Practicing in a controlled environment will help you be prepared to quickly and efficiently handle such scenes in real time photo shooting.A common photography problem: shaded objects in digital photos