Digital Cameras Explained

What is a digital camera?

A digital camera is similar to any other camera that you might have used or seen but it does not use a conventional film to store its photos - it uses a memory card to save the pictures digitally. This has a number of great advantages including the facts that results are instant (so you know that the picture is a good one) and that you no longer have to pay for film and processing. Originally, digital cameras were designed to be used solely with computers but now with the advancement in minilabs (such as our Fuji Digital minilab at Haywards Heath - the frontier 370 and the Frontier 5700 at Burgess Hill), you can now use a digital camera and get a full set of prints without the need of a computer of your own. If you do have a computer though, pictures can be loaded on to the computer and you can edit the images, e-mail them to friends and family all over the world, put them into presentations, on your website, print them out up to A3 in size at home or do anything else that you might want to do with them!

What are the advantages of a digital camera?

• Instant results (and you can view the pictures straight away wherever you are with the LCD screen on the back of virtually all digital cameras). This means that you know that the picture is good (otherwise you can just delete it and take another one).
• No processing costs. Digital cameras save pictures on memory cards and these do not need processing like film does before you can see what you have taken. (If you want print outs of your pictures though this will still be a cost to take into account).
• Pictures can be loaded on to your computer for you to edit (for example, get rid of red eyes, add a title, remove the dustbin in the background, etc) - before you print the image.
• Smaller cameras: the smallest cameras that we sell are digital cameras, making them even easier to just slip into your pocket

So what are the disadvantages?

- Initial expense. Digital camera prices have come down steadily over the last few years and are starting to level out but they are still more expensive initially than conventional film cameras. However, because you don't pay each time for film and processing, you can get pictures stored on your memory cards for nothing!

From what I understand, if a camera has more 'pixels' this means that it is a better camera. Is this right?

Not exactly. If you are comparing a camera with exactly the same features, the same lens quality and everything else the same, then this is true. However, lens quality varies tremendously (as do many other significant features) so a 4 megapixel camera with a poor lens can often be worse than a 3 megapixel camera with a very good lens. Most of the cameras that we sell (and therefore recommend) have very good lenses but there can be some models with even better lenses, which might be extra bright or particularly crisp. If you are unsure about the quality of lenses on digital cameras then please ask us for some help.

How many pictures can I save on a digital camera?

This is a very common question which doesn't have a fixed answer. Pictures are usually saved on memory cards (although some cameras do have some internal memory) - which are the equivalent of film in a 35mm camera. So firstly it depends on what card you are trying to save pictures on. Cards vary in size from 64Mb up to 8000Mb (8gb) (although most common are the 256Mb and 512Mb varieties in compact cameras and 1gb to 4gb in Digital SLRs). The more memory, the more pictures you can store. Now comes a further complication to the answer to this question: digital pictures can be saved in a number of different qualities so that you can save a high quality picture with lots of information or a low quality picture with little information. Clearly, a better picture quality will require more memory and so you will get fewer pictures on your card. It is worth knowing though that each picture that you take can have a different quality - you just select it before you take the picture - allowing you to save excellent and reasonable quality pictures on the same card. A further complication is that even if you set a camera to a fixed quality, the pictures may still vary in size a little. For example, if I took a picture of an all-white wall then there is not much information in the picture in the first place so it can be saved in a small file. Conversely, if I took a picture with a million different coloured beads in then there will be a lot more information for each colour in each dot of the picture.

So, although we cannot give you a definite answer to this, we can tell you that a fairly good quality picture (although not of the best quality on any of the cameras) has a file size of around 1Mb. This means that a 64Mb card will store roughly 64 pictures, and similarly with any other size card. You can set the lower resolutions and get several times (2-3x) this many pictures on your card but if you want the best quality (for enlargements or selective enlargements in particular - and we would always recommend that you do this so that you have the option to enlarge your photos at a later date) then you are best off using the best setting that the camera offers. This varies according the compression and the resolution (ie. the number of megapixels) of the camera - but the same principle applies - the better the pictures, the fewer the pictures.

But don't forget: if you don't like a picture you can delete it wherever you happen to be and when you've copied your picture on to your computer (or just printed them) you can delete it off the memory card and keep reusing the storage capacity of the card.

Do you get different quality memory cards like you get different quality film?

Another common question, stemming from the fact that the memory card is the equivalent of film in a 35mm camera. However, digital pictures are all stored digitally on the memory card and so each bit of information is either a '0' or a '1'. These 0's and 1's make up the whole picture and because it is not possible to have a "bad quality" 0 or 1 then the picture is not affected in anyway by different "quality" memory cards.

So the short answer is No. However, memory cards do vary in price between different manufacturers and there is a very good reason for this. It is to do with the reliability of memory cards. They are not 100% reliable all of the time (although it is very unlikely that you will have a problem). What this can mean is that a memory card can become "corrupt", just like anything stored digitally on a hard drive or other type of storage. We only sell Fuji , Olympus , Sandisk and Sony memory cards because these are the most reliable. We have in the past sold other manufacturers cards as they offered our customers slightly cheaper prices. However, these weren't as reliable in the long term so we have now stuck to these leading brands.

Another reason for a price difference in memory cards is the speed at which they read and write. Please see question after next for more details of this.

You say that memory cards are not 100% perfect so should this worry me?

No. Although there are some sensible things that you can do to make the risk of losing pictures even less. The most common reason for a card becoming corrupt is when the card is removed from the camera while it is still being written to or being read. To avoid this, just simply wait 2 seconds after you have taken a picture or viewed a picture before taking the card out.

What does it mean that one memory card is faster than another?

Memory cards are now available in different speeds. The majority of "standard speed" cards are around 8 to 12x speed. This means 8 to 12 times the rate of 150Kb/sec, which equates to somewhere between 1,200Kb/sec and 1,800Kb/sec. Most memory cards refer to their speed in terms of a multiple of this but there are some that quote their speed to be in Kb/sec or Mb/sec (which is approx 1000Kb/sec). However, just because a card is able to read or write this quickly it does not mean that it will be able to do it in all devices - much older cameras for example are usually a fair bit slower than the cameras on the market today. Also, cards may write at this speed but read slightly faster - it varies again by card and device.

Sandisk have now different ranges of memory cards which equate to different read/write speeds.

• Sandisk "Ultra II" range of memory cards which have a 10MB/sec read speed and 9MB/sec write speed. This equates to about 60x read and write speeds so they are incredibly fast.
• "Extreme III" memory cards have a rating of 133x. The other advantage of these two ranges is the 10 year warranty on them. The cards have also been tested to -25º C to 85º C for proven reliability.
• "Extreme IV" - These are the fastest range of cards we cureently supply. This range of memory cards have a read/write speed of up to 40MB/sec (based on SanDisk internal testing) and are designed to meet the critical speed and performance needs of serious professional photographers. Significantly improved workflow efficiency for capturing, viewing, upload and transferring large image files. Like the Extreme III cards they have been built to perform in the most extreme environments and temperatures from -25º C to 85º C. They also come with Data recovery software which ensures your photos will always be there (even if you delete them accidentally)

So what difference does it make to having a fast or slow memory card?

The main advantage of a faster card is when you are taking pictures. The camera writes to the card faster and so there is less time to wait before you can take another picture. Some cameras do have memory buffers to allow you to do this but it is still much quicker on a faster card. Also, when you are flicking through your pictures on your camera or even on your computer via the camera or card reader then it is much quicker and far less annoying to have a faster card with very little delay.

It is also much faster to download your images to your computer, which on a large memory card can make several minutes difference to the time it takes, but many people find that when they are at home they don't mind so much the time it takes compared to when they are using the camera out and about when it is the other delays that make more of a difference.

What other features should I look for in a digital camera?

Other than the pixel count, there are some other differences between models which you should be aware of. The first thing you may notice is the size of the LCD screen on the back. Most cameras have a 1.8" or 2 " screen. Some are now available with screens up to 3" in size. This makes it easier to compose you pictures and makes it nicer for reviewing shots which you have already taken.

The higher end cameras from each manufacturer can be bought with some advanced technologies such as WI-FI and Anti Shake. Wi-Fi is basically a technology found in many computers and even printers nowadays that allows documents to be sent without wires between devices. This can include photos from digital cameras so you can shoot a picture and have it instantly sent to your laptop without the need for cables or the like.

Another useful development is Anti-Shake systems built into the cameras. These are often in the form of gyros built into the lenses that detect camera shake and then alter the position of the lens elements accordingly which creates a sharper image. This is particularly useful in low light situations when you might need a longer shutter speed to properly expose the image which often results in blurring due to camera/hand shake.

Movie mode: Most cameras have a movie function which records moving images and sound onto your memory card. The length of the video is normally limited by the capacity of your card and the life of the battery. Look out for two features regarding video, the frame rate(usually 25 or 30 frames per second) and the resolution(usually 640x480). The faster the frame rate and the higher the resolution the better. These videos can be downloaded to the computer just like your photos and also played back on the camera's LCD screen or played back through your TV with an AV cable. Whilst not as good quality as an actually video camera, and not likely to win you an Oscar, these movies are great fun and due to their small file size, perfect for e-mailing to friends and family around the world!

What is a digital SLR?


A digital SLR camera is like a film SLR camera except pictures are saved digitally like any other digital camera. This leads on to what an SLR is... An SLR, or Single Lens Reflex, camera is a camera body on which you can change the lenses. Why might you want to do this you might ask? Well this gives much more flexibility on how you take photos but more importantly they give the best possible results because the lens quality can be so much better than a compact digital camera. The added flexibility includes being able to add flashguns, use macro lenses, wide angle lenses, telephoto lenses, etc, etc! A digital SLR will also offer you much faster shutter speeds, full manual control, being able to see through the actual lens that the picture will be recorded through (as opposed to an additional lens that doesn't give you 100% accuracy as to what you are taking (although are reasonably accurate)) and much more.

  Why do my lenses for my existing SLR camera seem more zoomed in when I put it on a digital SLR?


Most Digital SLR cameras do not all have CCD sensors that are the same size as a 35mm film. It is then purely physics that explains that the smaller area blown up to the equivalent 35mm size will bring subjects closer when comparing digital and 35mm film results using the same focal length lens. The amount that the CCD is smaller than 35mm film affects how much closer the subject will be. Most of the digital SLRs on the market today have a multiplication factor of around 1.5x - 1.6x. What this means is that if your lens is a 50mm lens, then on a digital SLR with a multiplication of 1.5x, this lens will appear as a 75mm lens. This is therefore excellent news if you want to get closer in to your subject but not so good for wide angle shots.

There are cameras available that have larger CCDs and therefore have a smaller multiplication factor to take into consideration and there are even cameras now that have sensors that are the same size as 35mm film (also known as full size CCDs). These cameras will not have any multiplication factor to take into consideration at all.

Is my computer good enough?

The beauty about digital photography today is that you don't even have to have a computer to enjoy it! You can still take pictures, delete the ones you don't want, take your memory card with the pictures on in to a shop (such as ours) and get a good quality set of prints. However, if you want to do more with your pictures then you will need a fairly modern PC (say less than 4 years old). The specification of the computer varies for different models but many of the latest cameras recommend Windows 98 or above, with a Pentium 200MHz processor or faster and a minimum of 256Mb RAM. New computers bought in the last couple of years will have a much better specification than this and will process the data more quickly allowing you to do more things more quickly. When shooting in RAW mode, a higher specification computer is recommended.

What else do I need with a digital camera?

Virtually nothing (in theory). Most digital cameras come with everything you need to take pictures and download them to your PC, do some simple editing with some software and print them out (if you've got a printer). However, in practice this isn't all you need. To keep the costs down of the camera, they often come with small(ish) memory cards, no case, no rechargeable batteries (or no spare battery). This means that you are tied to your PC so that you can download the pictures on the card and re-use it and also limited to the battery life that comes with the camera.

So you tend to find that the majority of people will always choose a larger capacity memory card (such as 512Mb or higher), a soft case and depending on the type of batteries the camera comes with, spare/ rechargeable batteries.

There are many other accessories available to make life easier and your pictures more interesting! These include USB card readers, mains adaptor, batteries, battery grips, wide angle lenses, telephoto lenses, underwater housing, flashguns, filters, etc, etc! Please click here for details of the accessories that are available. If you are unsure of what you might need, please do not hesitate to contact us.

Many people already have printers but expect good quality photos from old (even black and white) printers. This unfortunately, is not a reasonable expectation and to get the best from your camera, you will either need to take the memory card in to a shop to be printed on a digital minilab or get a photo quality printer for your home. Please click here for details of the latest printers available. Again for any help and advice please contact us by phone or e-mail.

What is a Card Reader?

This is a small device that does exactly what it says. It reads cards. It is a computer peripheral that plugs into your PC, usually by the USB port (although there are Firewire and parallel port options). You then put your memory card from your camera in the slot in the card reader and you can then access the data like you were putting a floppy disk into its drive. This then has the following advantages:

• Faster to download (often readers are now USB 2.0 which is 40 times faster than the USB 1.1 connection on most cameras)
• Simply open your files straight from "My Computer" or from Windows Explorer - simplest way to download your images (no need to use only the software supplied with the camera)
• No need for messy cables that you have to plug in each time (the card reader can be left connected and sits in a convenient location by your computer)
• Don't drain your camera's batteries (because it isn't even needed to download the pictures)
• You can write back on to your memory cards, should you wish to, so that you can take your older pictures to show friends on your camera. It can also be used to backup your files on to a memory card

What is the difference between USB 1.1 and USB 2.0?

Speed. USB 2.0 has a data transfer rate of 480Mbps (or 60MB/sec) compared to USB 1.1 with a transfer rate of 12Mbps (or 1.5MB/sec) - this is 40 times faster! To take advantage of the faster speed of USB 2.0 you will need USB 2.0 ports in your PC. If you have bought your computer brand new since June 2003 then it is very likely that you have USB 2.0 ports. Otherwise you will probably have USB 1.1 or USB 1.0 ports. You can tell by looking at the Device Manager under Hardware in the System Control Panel - under the Universal Serial Bus (USB) Controller there will be a USB 2.0 Root Hub. This isn't a major problem because virtually all USB 2.0 devices are backward compatible so they will work with USB 1.0 or 1.1 computer ports but will only work at the slower rate. Should you upgrade at a later date to USB 2.0 you will obviously benefit from the faster transfer speed (which means less frustration while waiting for computers to do what you want them to do!)

What is a USB Cradle? (Also known as a Camera Dock or Docking Station)

This is a similar type of device as a card reader (see above) but also has additional benefits. It is again a small device which you permanently leave connected by the side of your computer in to a spare USB port. The cradle has sockets that plug directly into your camera when you place it on the top. You will then be able to download your images on to your computer by clicking on the download button (this varies according to which cradle/dock you have but often it is just a one touch button on the cradle itself). USB Cradles often also charge your camera's batteries at the same time, or at any time it is left in the Cradle. This makes it as simple as possible to both download your images and recharge the camera's batteries.

USB Cradles aren't available for all cameras, but it is becoming a more popular feature that many Casio, Kodak and Fuji Cameras offer, as well as particular Nikon and Sony models. Some cradles are supplied as part of the camera's standard accessories but others are optional.

I keep hearing about PictBridge, but what is it?

PictBridge is a new standard for the interaction between digital cameras and direct printers, regardless of the manufacturer of either the camera or the printer. A direct printer is basically a printer into which you can directly plug in your digital camera and print direct without have to download to a computer or even to have a computer. In the past many direct printers have only worked with cameras of the same manufacturer but now if you have a PictBridge printer you can plug in any digital camera (that is PictBridge compliant) in to that printer.

Technical Jargon explained:

Pixel/ MegaPixel

A 'Pixel' is another name for a dot. Lots of pixels (or dots) make up a digital picture captured on a digital camera. Different digital cameras can record different amounts of pixels in a picture. The more pixels that a camera can record the more information there is in the picture and so therefore the better the quality of the image. To be able to print good quality larger images you will need a camera with a CCD with a large number of pixels. Basic cameras have less than 3 million pixels (or 3 Mega pixel), while if you are looking to produce good quality images at greater than 8"x10" then you will need a camera with at least 5 million pixels (or 5 Mega Pixels). There are now cameras available that record over 10 million pixels in a single picture so make sure you get a digital camera with a large number of pixels.

File size output

Some cameras claim to have a 6 million pixel output. This is not a lie but it does mislead many people. Many of the Fuji cameras, for example, have 3 million pixel CCDs but will save an image that has 6 million pixels. This is a good feature to have but when comparing these cameras to others, it is best to compare the effective number of pixels on the CCD.

Optical zoom

This is usually expressed as a multiplicative factor (such 2x or 3x or even up to 10x on some models) and tells you how much a camera will zoom in compared to how wide the picture is. It is best to get as large a zoom as possible to cope with different situations and to be able to get the subject of the frame to fill the frame rather than just be a little dot in the middle. Please double check that a camera is referring to its optical zoom (as opposed to a digital zoom) since there is an important distinction - see below.

Digital zoom

This is a zoom where the camera takes the individual dots that make up the centre of the picture and make them bigger so that the image ends up to a larger size. This is very useful because it does not require any further re-framing (which could be done later on on a computer but would be an extra thing to do). However, because the resulting image is only using information from the middle part of the picture and blowing it up, the image quality is worse than if the digital zoom is not used. Hence it is better to get a camera with a large enough optical zoom to suit your needs.

CCD

This is the name of the sensor inside of the camera that is sensitive to light and converts the image into a digital format that the camera can save on its memory card. CCDs have different numbers of points on them that are sensitive to light and in general the more of them, the better the picture quality. The number of pixels (or dots) in the picture that it outputs is what is called the 'resolution' of the camera. It may also be recorded in 'megapixels' (or millions of dots). There are a few other types of imaging sensor such as CMOS or LBCAST which you may see in some cameras but these work in a very similar way to CCDs

Memory Cards

These are the digital equivalent of film. A memory card can hold a certain number of pictures, depending on the size of the card (expressed in Megabytes or MBs) and the size of the pictures to be stored on it. This varies enormously between the different settings on different cameras but as a very simply guide you can say that you get a reasonable picture quality (but not the best) from a file size which is about 1Mb so on a 64Mb card, you can get about 64 pictures. Roughly 1000Mb is 1GB and you can now buy cards with up to 4GB of space. These cards can store thousands of pictures or extremely long video sequences.

Compact Flash

This is a type of memory card. Canon, Nikon and Pentax are just some of the manufacturers of digital cameras whose cameras use this storage medium. It is the most common of all memory cards.

xD Picture Card

This is a type of memory card. Fuji and Olympus are the two main manufacturers of digital cameras whose cameras use this storage medium. It is the newest storage medium and there are plans for the near future for cards of up to 8GB in size.

Smart Media

This is a type of memory card, abbreviated to SM. Fuji and Olympus are just some of the manufacturers of digital cameras whose cameras use this storage medium.

Sony Memory Stick

This is a type of memory card. Sony was the first company to use these as a storage medium, although other manufacturers have also started to use Memory Sticks. Memory Stick Duo is also now available. These cards are roughly half the physical size of normal memory sticks and the newer cameras tend to use this size to reduce the overall size of the camera. They can be used via an adapter in full size memory stick slots.

MultiMedia Card

This is a type of memory card, abbreviated to MMC. Canon digital camcorders that have digital camera functions built-in are just some of the hardware available today that use this storage medium

Secure Digital Card

This is a type of memory card, abbreviated to SD. It is very similar to a MultiMedia Card in that it is exactly the same size and many cameras and other devices that use MultiMedia cards can also use Secure Digital (although this is not true for every single electronic device and the opposite is not necessarily true). Secure Digital cards have extra features over and above Multimedia cards but this depends on the device (cameras usually don't have any extra features with SD cards than MMC cards but some devices, like mp3 players do make use of the extra features).

Microdrive

This is a type of memory card. It is actually a very small hard drive and come in very large capacities allowing you to save thousands of pictures all on one card. The card is very similar in size to a compact flash card and many cameras that can store pictures on compact flash can also use microdrives as a cheaper way to store hundreds of photos.

Mobile Phone Memory Cards

Many of the newer mobile phones now accept different forms of memory cards as a way of increasing the memory of the phone and transferring data between phones and other devices. These cards all work in pretty much the same way but differ in capacity and physical size, much like normal memory cards for digital cameras. Different types of card currently used include, Mini SD (secure digital), Micro SD, RS-MMC (Reduced Size Multimedia cards) and MMC-DV (dual voltage). Transflash is currently the smallest type of card available and is commonly sold with and adapter to allow it to be used in regular SD card devices.

Compression

This is what a camera or a piece of imaging software does to a picture to make the file size smaller. Basically a picture that takes up a lot of memory can be compressed so that it doesn't take up so much. This has the advantage that it uses up less space so that you can save more on your card, but has the disadvantage that in reducing the file size, you usually reduce the quality of the picture.