Digital Dust Spots

Dust Busters!
How to clean dust off of your DSLR's sensor without ruining it (hopefully!)

Do you see mysterious dark spots on your DSLR images?

If the answer is no, ignore the rest of this article and be happy. But if you have seen these spots, read on. Your DSLR probably has dust on its sensor--a normal, but inconvenient, fact of life when using digital cameras with interchangeable lenses. Removing this dust from your sensor requires a delicate touch.

I'll show you how.

A tough spot: 100% enlargement of highlighted area in above image at right reveals two spots caused by dust on a DSLR's sensor. It's a common problem, and fixing it yourself comes with risks...unless you do it right.


Where did those spots come from?

Spots on a digital image are sometimes attributed by users to dirt on the lens or SLR mirror, but this is almost never the case. The mirror is out of the optical path when an image is made, so even large amounts of dirt on the mirror will not show up in the image. Dirt on the lens elements will also very rarely show up as spots on the image since it's so far out of focus. You might see dirt on the front element of a fisheye lens if it's set to its minimum focus distance and stopped down, but the optics of normal lenses won't produce images of dust particles inside the lens.

Dirt can potentially enter your camera whenever you change lenses. That's why this isn't a problem with digital cameras with built-in lenses. One way to minimize dirt is to point the camera down while changing lenses. It won't stop all dirt, but it may minimize spots.

Check your sensor

If you don't know if your sensor has dust, here is how to check. Put a lens on your camera, set focus to infinity, exposure compensation to +1, and the aperture to its smallest value (largest number)--at least f/22, f/32 if you have it. Hold the camera a foot or two in front a uniformly illuminated target that fills the frame and shoot. Exposure may be several seconds, but that's OK. You don't need to hold the camera particularly steady. You want the exposure to be uniform, which is why you've deliberately defocused, so camera motion will make no difference. Look at the image. Do you see dark spots? If so it's 99% certain you have dust on the sensor.

At wider apertures, the dust specs will be much less visible. At f/11 they may be very faint and at f/8 or wider apertures they may be undetectable. If the aperture setting doesn't affect the appearance of the spots, and they are very sharp and well-defined, they are more likely to be sensor defects than dust.

Can you spot spots?

Below are three 100% crops from a test image. On the left is a portion of the original image, which was shot at f/5.6. It's very, very hard to see any evidence of a dust spot. In the center is the same shot, but with an extreme histogram stretch to bring out the very low contrast detail. You can now see a large circular area that's somewhat darker the the background. That's the shadow of the dust spot on the sensor. Finally on the right is a crop from exactly the same position in a test frame shot at f/32. The dust spot is quite obvious without any manipulation of the image.



Some cameras, notably the Olympus Evolt DSLR bodies and the new Sony Alpha DSLR, take some pains to remove dust from the sensor by rapidly vibrating, "shaking" the dust off the surface. By all accounts this system works pretty well, but it doesn't help owners of Canon, Nikon, Pentax, Leica, and earlier Konica-Minolta DSLRs. Even Olympus and Sony DSLR owners might one day encounter dust/dirt on the sensor that can't be shaken off!

If you see dust on your sensor (and eventually, everybody will) you really then have only three choices:
1. Ignore the dust spots and clone them out if and when you see them. This will get very tedious and time consuming, so it's really not a very good option if the spots are visible under normal conditions. If you only see them at f32 after increasing the image contrast then you can probably live with them. All sensors will show some dust if you look closely enough.
2. Send the camera back to the manufacturer or your favorite repair shop for cleaning. It will probably cost you at least $50 and you may be without your camera for 2-3 weeks, but there's a good chance it will come back dust free. There's also a chance it will come back with less dust, but still a few specs. Even if it does come back clean it will probably pick up dust with a few weeks of use. Then what do you do?
3. Clean it yourself. This would be the obvious choice if it were not for a very small chance you could do some damage and end up with a $200 repair bill. Many, many people have cleaned their sensors themselves without any problems, but if you are clumsy, you don't use the right cleaning tools, or are just very unlucky, there is small chance you could have problems.
Why I vote for option three

Since even after you (or someone else) has cleaned your sensor it will eventually get dirty again, learning how to clean it yourself will save you a lot of time, money and frustration in the long run.

The surface of the sensor (see the diagram at right, which shows the construction of the Canon EOS D60's sensor) is about as delicate as the surface of a multi-coated filter. In fact it is pretty much the surface of a multicoated filter since the actual sensor itself sits behind anti-aliasing and IR blocking filters in almost all DSLRs. If you can clean a muticoated filter without damaging it, you can probably clean a digital sensor surface. The only caveat here is that even the smallest scratch will show up on the sensor, while a small scratch on the filter may go unnoticed.



Technical note: The dust isn't actually on the sensor surface. It's on the surface of a filter which is in front of the actual sensor itself. This is why dust shows up more at smaller apertures. Since the dust spots are some distance from the actual sensor pixels, a wide aperture lets in light which can "go around" the dust spot. It's a bit like using a large softbox for lighting. Shadows (and what shows up in the image is the shadow of the dust spot) are light and soft. At small apertures it's like using a small pinpoint spotlight and shadows are dark and hard edged.

The following images show small dust spots as f/22 and f/11. They have been greatly processed to show the dust spots as clearly as possible. On the straight images the spots are totally invisible at f11 and only very faintly visible at f/22



Here's what very dusty sensor looks like at f/29. This is a 100% crop from an original image, no processing applied. After cleaning no dark spots could be seen.



There are several ways to try to remove dust from the surface of a digital sensor. All require first raising the DLSR mirror and opening the camera's shutter. Most DLSRs have a Cleaning mode which does both of these things, leaving the sensor visible if you remove the lens from the camera.

Method 1 - The Blower

This is the safest way of trying to clean a sensor, though it's probably also the least effective. Canon, for example, recommends a blower bulb, with the tip of the bulb held no further into the camera than the lens mount. The theory is that with bursts of air you can blow dust off the sensor. What you may actually do is redistribute the dust inside the camera. If there's more dust on the sensor than around it, you'll may end up with less dust on the sensor. However my attempts at this method usually resulted in more dust on the sensor than I started out with!
• Good points: Zero possibility of damaging sensor. Even if the shutter should close you're OK if you're outside the body with the blower. Easy to do, so it's always worth a try.
• Bad points Doesn't seem to work very well; may result in more dust than you started out with.

Caution: Do not use any sort of "canned air" for this. It may be too powerful and the types that are liquid driven can "spit" liquid in the gas stream and if that happens you may find residue left on the sensor.

Method 2 - The Brush

If you can't blow the dust off the sensor surface, maybe you can brush it off. The brush actually picks the dust up and removes it from the camera, rather than just dislodging it and having it land somewhere else inside the camera body.

A company called Visible Dust introduced a line of very high-tech brushes which have bristles made of specially-shaped materials and are treated in a high-tech way (in a plasma chamber), producing a brush that won't damage the sensor but will attract dust onto the bristles rather than just pushing it around on the sensor. From all accounts, the Visible Dust brushes do a very good job of sensor cleaning, though they are not inexpensive (up to $280 for complete brush kits for 1.3x, 1.6x, and full-frame sensors.
• Good points - Usually works, very little chance of doing any damage
• Bad points - Commercial brushes aren't cheap, but they're cheaper than a new sensor and cheaper than having a professional clean the sensor a few times.

The Brush technique--DIY version

The research scientist in me wondered if I could get away with using a cheaper brush. The basics of a desirable brush are that it should use fine, soft, synthetic fiber bristles and the handle should be insulating. This will, in theory, enable the brush to hold a small electrostatic charge which will attract dust and "vacuum" it off the surface of the sensor as the brush passes over it.

I found a very inexpensive makeup brush at Wal-Mart (shown). I don't remember what it cost. Probably less than $1.

The most important property of the brush isn't that it removes dust, but that it doesn't mark the sensor. The brush has to be clean and free from grease and oil. You can wash it with a mild detergent and thoroughly rise it with clean water, then test it by brushing it over a clean multicoated filter a number of times. If you see any marks left, it's not clean enough to be used on a sensor. You can put a small static charge on the brush by blowing air through the bristles (which also should blow out any trapped dust) using either a blower bulb or compressed gas. The small static charge attracts and holds dust particles without risking sensor damage.


For me, this brush worked quite well in removing the dust on my sensor as shown by the series of images above. Since the brush is only about 1cm wide it took a couple of passes to go over the whole sensor. Sometimes it's necessary to do a 3rd or 4th pass to remove all the problem dust particles. The Visible Dust brush is wider and can clean the sensor in a single pass.


Is it better than a Visible Dust brush? Probably not. Is it safer? I don't think so, in fact it's probably more risky. Is it cheaper? Yes, it is. Could it damage the sensor? I can't say for sure it won't, but it hasn't yet.




Method 3 - If all else fails...full contact

If the dust refuses to move with either a blower or a brush, somewhat more drastic measure may be called for. You may have to make harder physical contact with the sensor surface with some sort of cleaning device. Since this method has the most physical contact with the sensor, it's the most effective at removing stubbornly attached dust or dirt--but it also has the highest chance of damaging (scratching) the surface of the sensor assembly.

The first method of removing stubborn individual dust specs is to use a SpecGrabber, made by Kinetronics. This is an insulating plastic rod with a small pad on the end. The pad provides a high adhesion surface for individual dust specs, higher than the force holding them to the sensor surface (if you're lucky!), so it will lift the dust off the sensor. The pad leaves no residue and uses no solvent. It can be washed and reused. The only trick here is finding the individual dust specs! They are usually too small to be seen with the naked eye and the tip of the SpecGrabber is only a few mm in diameter, so you may have to hunt around for them, checking the sensor each time to see if you've got them.

The second full-contact method is to use a lens tissue in conjunction with a solvent cleaning fluid. This will clean the whole sensor at once so for a sensor with a lot of dust will be faster and easier than trying to remove each with with a device like the SpecGrabber. You can make your own tools to do this, or you can buy them.

To make your own what you need is a soft but fairly rigid support, about 15mm wide by a few inches long and 1-2mm thick. This could be a Popsicle stick, a modified plastic knife, a modified kitchen spatula or a strip cut from an old credit card. The idea of a soft but rigid support is that if you should turn out to be physically inept and instead of wiping the tissue across the sensor you tear the tissue and/or scrape the support across the sensor, you'd rather it was soft like plastic than hard like steel. You then take a sheet of lens tissue, fold it lengthways several times until it's about 15mm wide, then fold it in half and place it over the stick as shown in the figure below. 15mm is the approximate height of an APS-C digital sensor.

Do not touch the tissue in the area which will contact the sensor. Not only will you transfer grease onto it from your fingers, you may transfer dust and grit. Running a greasy, dusty, gritty tissue across the face of the sensor is not recommended.



You then moisten the end of the "swab" with pure methanol or other high-quality, no-residue cleaning fluid such as that made for cleaning muticoated optics. Do not use Windex or any similar household cleaning fluid! The key here is "moisten". You don't want liquid dripping off. It should be wet, but not that wet.

Hold your breath, engage the sensor cleaning mode on your camera to expose the sensor and gently wipe the swap across the sensor from one side to the other. The idea is to contact the whole width (height) of the sensor as you wipe across it from edge to edge. If you have to do it again you will use another clean sheet. "Clean" is important word here. Don't try to economize by using the same tissue twice.

You don't need to scrub the sensor or apply too much pressure, but you do want to apply enough pressure that the tissue fully contacts the sensor surface. The trick is that you don't know how much pressure this is until you've done it. Perhaps a couple of practice swipes across a filter might give you a better feel for what's required. Obviously you use a fresh piece of lens tissue before cleaning the sensor.

Now, do another dust test by taking a shot of a uniform bright surface with your lens stopped down to f/22 or smaller. If you are lucky you will see very few (if any) dust spots. If you are unlucky you will still see multiple dust spots.

If you see some dust left (and you don't see any damage!) you can repeat the process and hope to remove it. However the trick here is not to push things too far. Removing every last tiny spec of dust that's visible at f/32 is not necessary. Even if you do manage to do it, within a day or two I'll bet you'll find a few small dust specs back on the sensor. You do not want to clean the sensor any more frequently or vigorously than absolutely necessary. The less contact you have with the sensor, the lower the risk of doing any damage.

You can buy special cleaning swabs for this purpose such as those sold under the name Sensor Swabs made by Photographic Solutions Inc. They are assembled in a clean room and sealed. The chance that they will scratch the sensor is very, very, very, very, very low (unless you get dirt on them yourself after you unwrap them). The downside is that they are $4 each and sold in packs of 12, so they will cost you $48. However this is much less then the cost of replacing a scratched sensor. You can also buy special cleaning fluid (such as Visible Dust Smear Away Solution Kit, Tough Sensor-Stain Remover (shown), which costs around $20 and will not damage the sensor or leave residue.

Lens tissue is much cheaper (about $2 for 50 sheets of Kodak Lens Tissue). You want optical grade lens tissue. I've used lens tissue on lenses for years without a problem, including cleaning some pretty delicate optics such as dielectric laser mirrors, so I'd say the chances of a problem are very, very small, but they are never zero. I've also cleaned my DSLR sensor maybe a dozen times with then, again with no problems.

Note: Be sure you buy untreated lens tissue, not silicone impregnated lens tissue sold in eyeglass stores. If you smear silicone oil on your sensor you will not be happy and you'll be spending quite a bit of time trying to clean it off.

Caution and Disclaimer
While many people have reported success in cleaning their sensors using these techniques, I have seen one report of someone who scratched their sensor trying to clean it using a tissue. They probably weren't working in a clean environment and picked up a tiny spec of grit on the tissue and they may have used too much pressure on the sensor. If you don't have good mechanical skills and a delicate touch you might want to think a fewtimes about whether you really want to do this yourself. I've used the brush technique many times and I've also used lens tissue supported on a modified plastic knife. There was no damage and the sensor ended up very clean in each case If I hadn't managed to do it without damage or it hadn't removed the dust, I wouldn't have written this article. When using the proper professionally produced cleaning tools designed for digital sensor cleaning (rather than home made devices) the risk of damage is very low, however there are no absolute guarantees.

A scratched sensor isn't a total disaster, but replacing the sensor (or more likely the covering filter) will probably cost around $200-$300.

Best Digital Camera

Every month manufacturers are coming up with a different digital camera to entice potential customers. You can spend hour trying to figure out which is the best digital camera out there.
You can go the mall and you may see a seven mega pixel camera, 1G expandable memory, a built in microphone and surround stereo, even video playback capability with different scenic modes.
And we get confuse because the manufacturer claims that this is the best digital camera out there on the market. And so we always want to have the best, and so splash out our hard earn cash and makes the purchase. Then in a few months or so , there is another best digital camera.
And so it confuses us. What makes a digital camera, the best digital camera? So eventually we are left confused. What makes a digital camera, the best digital camera?
One of the most important feature of a digital camera is the mega pixel category. The higher the mega pixels the better the actual photograph will come out. One mega pixel is equivalent to one million pixels. The actual resolution of your image is determined by the mega pixel of your camera. This means that as you enlarge the picture, you would get more detail and less blurry colors
A good digital camera will nearly always have a large LCD screen to help you frame your subject without you having to use the view finder. This also helpful when reviewing your images, the best LCD size would be 2.5 inches and higher.
The zoom feature is also very important. Some digital cameras have both digital and optical zooms. The higher the optical zoom the better. Optical zoom is always better than digital zoom. Optical zooms of between 3x and 10 x are better, the higher the optical zoom the better the digital.
Another important feature of a digital camera is the memory card. Always make sure you have the right memory card. There are many different types of memory cards out there like XD, SD, flash card and the memory stick. These different types of memory cards works with different digital cameras. Choose the size of memory that you need, if you want to take many pictures 32MB to ! G
The key point to find the best digital camera is to find one that will best fit you and your lifestyle. The final decision in choosing the best digital camera, is to buy one that best fit you and the purpose for which it is intended. Do not buy the latest or the one from any manufacturer that claims there's the best digital camera on the market. The best digital camera you can buy will be the one that will enjoy.

Batteries

You need batteries to power your digital camera otherwise you won't be able to use it. Most digital cameras use the standard-sized AA batteries which are reasonably priced and easily available anywhere. However, you must invest in rechargeable batteries as digital cameras tend to use a lot of power and you might find that your batteries are dead after a few shots. A lot of people especially when they are sightseeing tend to leave their cameras on. This, too tends to drain the battery.
There are different kinds of batteries available for digital cameras today. The regular alkaline batteries are all right to use in an emergency but not on a regular basis. They just don't have the power to last for more than a couple of shots. When they are recharged, the power you get from them is even less. Digital cameras need batteries that can cope with the high amounts of energy they need, especially when you use the flash.
The most popular batteries for digital cameras are the rechargeable NiMH or Nickel Metal Hydride batteries. They don't cost much and are definitely better than the standard ones you get. They could give you up to one hundred shots if you are careful with how you use your camera, switching it off when you don't need it. Of course, if you are into more than just the aim-and-click photos, you must be prepared for the charge going fast, especially if you use the flash or you adjust the focus and zoom a lot. Yet another advantage is that these are environment-friendly as they are non-toxic.
When it comes to charging these batteries, make sure you have a good, reliable charger. Remember that batteries can get overcharged so look out for one that has an automatic switching-off when the batteries are fully charged. Always charge all the batteries your camera needs to be powered at one go - whether two or three or four. This way, they are all equally charged when you put them in.
Some digital cameras have to use lithium-ion batteries. The advantage of these, though they are more expensive, is that you can store them and they don't lose their charge. You can use them for twice as long as the NiMH batteries. Most manufacturers give you a lithium-ion charger when you buy your camera. If they don't, just make sure you buy one as then they come as accessories.
You digital camera is only as good as the shots you get. If you chance upon a one-in-a-million view and your batteries are dead, it's a waste of a view and the waste of a camera. Your batteries, no matter how good, are only good if they are well-charged. So invest in a good battery charger. One in which you can control the time of charging so your batteries don't get overcharged. Once you have your batteries and charger in place, the world is yours, literally, through your viewfinder!

Camera Memory

The digital camera is essentially a computer-based device, whose core is controlled by the computer. And as a result the photographs are stored in a location called memory. Now, this concept is or paramount importance in discussing digital camera. Strictly speaking, digital camera memory is where digital pictures are stored inside the camera. The digital camera memory is an essential and often a very neglected and overlooked section of equipments for digital photography and camera. There are many types of memory available for digital cameras, and it is a good practice to mull over what type of memory a camera uses before buying a digital camera. This discussing is aimed in revealing some of this relevant information!
Knowledge of the digital camera memory is very essential for using such a camera and capturing photographs. The most common form of such memory is a memory card. These are reusable, have a limited capacity and can always be installed when required in excess. A person needs to be well informed about enough memory available for taking photographs. And accordingly make arrangements. Generally, digital cameras come available with low capacity memory cards, and it is a wise purchase to acquire higher capacity memory cards in order to budget for an additional card for later use.
With the increment of a camera mega pixel counts, it becomes essential to use higher capacity memory cards. Some of the small sized cards are for example the 64 megabyte cards and larger ones are like 1-gigabyte cards or combinations of megabyte cards.
Digital camera memory is available in many shapes and facade depending on the type of digital camera that is being used and even and the number of pictures that are required to be stored in the digital camera memory. These different types of memory are solely dependant upon the requirements of the digital camera, like for example a camera using compact flash type 1, requires the use of compact flash type 1 digital camera memory. Other examples of types of digital camera memory are Compact Flash Digital Camera Memory. It is suitable for rugged and rough handling and is also resilient for incessant usage. This is also small in size to assist better handling and flexibility. What more, it is cheap and anyone can afford it!
Generally, the sizes of a digital camera memory are as follows, 64 MB, 128 MB, 256 MB, 512 MB, and 1 GIG. Again, the digital camera memory depends upon the file format used to store photographs upon and the compression used by the manufacturer when storing digital images into memory.
Coming to the concluding portion, it is recommended to get hold of one 256 megabyte or two 128 megabyte cards for a 3-5 mega pixel compact digital camera. For higher resolution photographs, 512 megabyte and 1 gigabyte cards are also available. These are some of the guidelines for revealing the true facts about the different digital camera memories and their secrets. Summing up in a few words, with such a powerful tool as the digital camera, a proper selection of memory can help a person achieve the glorious tasks of freezing a precious moment from life for eternity!

Considering Digital

Since starting a website which concentrates on digital products, I regularly get asked for advice on what type of digital camera I recommend, or what brand is superior.
Unfortunately It's not a simple query to answer as there are numerous makes and types of digital cameras which only serve to add to the confusion. If it were simply a question of reviewing the cameras and comparing prices it would be easy, but when comparing digital cameras you need to consider each separate function.
Digital Cameras possess numerous functions, with the cheaper varieties having many less options than their costly counterparts. Conversely, a low cost digital camera is much easier to learn how to operate.
More costly digital cameras have additional features and you need to review what features are available. You must determine what you are going to use the camera for so you know what features are most important to your needs.
With all of this in mind, I have set out the eight most important considerations to make prior to purchasing a digital camera:
1. Does it possess "Exposure Compensation?" This is an important aspect as it allows you to alter the light setting.
2. Can you turn the flash on and off? Automatic flashes are good, but you should be able to control this setting.
3. Does it have automated red-eye adjustment?
4. What size images will it take?
5. is the camera suitable for close up shots? This is important if you are taking photographs of small objects.
6. How easy is it to use?
7. How strong is it? I have seen expensive digital cameras dropped on the road, so a sturdy camera is likely to withstand this type of treatment much better than an inferior one.
8. How does it compare in price to similar models?
You can study digital camera reviews on the web, but in my opinion, you need to physically test out the camera. Before I purchased my latest digital camera, I went to my local camera store and took pictures with different cameras, using some items that I wished to upload to my website and discovered what was best....it was hands on testing.
Finally, make sure you look at the pictures on a computer screen. The small display on the back of the digital camera is not an adequate indicator of the cameras quality.

Digital Difference

Digital Cameras use lenses and a shutter to capture light inside the body of the camera just like traditional film cameras, but that is where the similarity ends.
Instead of using film to capture an image as the traditional cameras do, the digital camera captures the image using an image sensor.
These sensors are completely electronic in their operation. They have various internal electronic devices to measure light intensity and a host of other duties.
The complexity of the image sensor determines its rating, measured in MegaPixels. The higher the number of megapixels that a digital camera offers, the greater the clarity and quality of the resulting picture. Also the higher the megapixel rating of the digital camera, the higher the cost of the camera.
Digital cameras function by converting light into an electrical signal that is, in turn, converted into binary (1's and 0's) so they can be processed through the digital camera's on-board computer. After the binary numbers are processed they are stored on the digital memory card or floppy disk.
The digital camera processes the light in such a way that the light is converted into the primary colors of Red, Green and Blue using internal filters. The photographs must be further refined by computer processing to produce the full color photograph. This process is called Demosaicing.
Many cameras offer photo sharpening to make the digital photographs clearer; usually, there are controls on the digital camera to adjust brightness, contrast, and color saturation.
After all this is done -- inside the digital camera -- the last step is to compress the image and then store it on the memory card.
To load images from a digital camera onto a computer and give you the ability to process the digital picture manually, requires a digital camera that offers this cability. If you would like this feature you should ask if the camera you are considering includes it before making your purchase.

Memory Cards

Now that you have finally upgraded from a traditional 35mm camera to a new digital camera, you will come to realize that the digital camera no longer needs the traditional film to store images, but instead uses a modern digital storage medium called the memory card to save all the precious pictures.
To put it in simplest terms, a memory card is an electronic data storage device. It is also referred to as a flash memory card. Apart from digital cameras, you will find the memory card in use in many types of electronic equipment such as the handheld and laptop computers, cell phones, music players and video game consoles.
Generally, you will find the memory cards in solid state, but sometimes they are also available in a non-solid state, though these types of memory cards do not use flash memory. These are based on cutting age technologies and used mostly by the gamers and the technical professionals and are often referred to as "mem-cards" by these techies.
There are different types and qualities of memory cards using various types of flash memory format. Many of the leading electronic companies in the world offer a wide range of models packed with many state of the art features, including high re-recordability, power-free storage, compact size and many more.
It was during the early 1990's that memory cards were introduced to the market for the first time, and it soon revolutionized the whole concept of data storage in the PCs, cell phones and other industrial applications. The late 1990's and early 2000 witnessed the competition amongst electronic giants heat up as they battled to introduce more and more sophisticated and compact memory card formats to the market, such as xD Picture Card and Memory Stick, thus meeting the growing need for smaller and smaller memory cards for compact electronics such as PDAs, cell phones and digital cameras etc.
The result is that today the market is flooded with a new generation of memory cards in a variety of formats ranging from SmartMedia and CompactFlash to the more sophisticated Memory Stick variants and xDs. In recent years the more popular memory card for digital cameras is the SD/MMC but with stiff competition coming from the Memory Stick formats such as xD and CompactFlash.
Memory cards are manufactured by many of the world's leading electronic companies and you can get the device in the electronic and computer section of virtually any computer or electronics store. The cards come with different speed limit and varying memory sizes, and these differences account for the wide fluctuation in their price range.

Quality Lenses

Selecting the right lens is critical when purchasing a digital camera. Basically, lenses can be categorized this way: fixed focal length, retractable zoom, fixed zoom and interchangeable lenses.
Fixed focal length lenses are the cheapest and simplest to use. Designed for those on a very tight budget, children or real novices, fixed focal length lenses typically offer only a wide angle view, which can be perfect for landscapes and group photos. The quality of the pictures taken using this lense, however, is not that great. Fixed focal length lenses can’t zoom in distant objects and they don’t accept converters. An autofocus lens, with a selectable macro or landscape focus mode, is often a better selection.
Retractable zoom lenses extend whenever the camera is turned on and retract when it is shut off. This type of lens is reasonably priced and takes decent pictures. A retractable zoom lens gives you a very compact digital camera style while fully protecting the lens. It offers a limited zoom range that magnifies two to three times. Retractable zoom lenses do not support filters or converters and slightly delay the start-up time of the digital camera. They also have limited manual focus controls.
A fixed zoom lens will accept converters, filters and flash rings. These extra features will allow an experienced photographer the ability to take beautiful close-ups, wide-angle and telephoto photography. A fixed zoom lens allows a magnification of up to 12x. Fixed zoom lenses offer advanced and precise zoom and manual focus controls through rings on the lens instead of buttons. This type of lens might be a bit complicated for a novice and it might be a bit bulky to be convenient.
A serious amateur or professional will use a digital SLR with interchangeable lenses. These fully detach from the camera and are replaced with a different lens. If you already own lenses for a traditional film camera, you can usually find a digital camera with a compatible SLR body. A digital SLR is the most flexible lens for all shooting situations. An added advantage is that if you want to upgrade your lenses, you can do so without buying a new camera.
Of course, the lenses can be quite expensive. They can also be quite heavy and inconvenient to carry. If you are not very knowledgeable about camera lenses, the options may be confusing and if you understood your lenses on a traditional film camera, you may be confounded by the focal length on the digital. The learning curve is a bit steep and long, but the picture quality makes it well worth it!