The camera was the only disappointing feature of the original iPhone and the iPhone 3G, as both were limited to 2 megapixels, decided on their own focal point and couldn't do video. The 3GS fixed all of that, upping the resolution to 3 megapixels, introducing tap to focus and recording video. We'll concentrate on the 3GS camera here.
In its default mode, the camera is set up for taking still images. You tap on the item in the image on which you want to focus, and take the picture by tapping the shutter button below it (see below right). The last picture you took is shown in the thumbnail to the bottom-left of the interface. Tapping this takes you to your camera roll from which you can manipulate and share your images.
Moving pictures
The iPhone 3GS camera is also a surprisingly competent video camera. The switch in the bottom-right corner of the interface toggles between still and moving images, allowing you to capture smooth motion at 30 frames per second with a maximum resolution of 640 x 480 pixels. Naturally, it also records sound.
The clever part comes when you have finished recording your video and saved it to your camera roll.
Clicking on it in the library calls up the video — just as it calls up a photo —but with a few key differences. For starters, the opening frame is overlaid by a play button. Tapping this starts playback.
More importantly, though, above the image is a film strip showing the frames that make up your video. Tapping on this lets you edit the movie to contain just the
The video interface is similar to the one for photos, but with an extra button for playback. Use the yellow sliders around the film strip to trim the movie to just the section you want .
portion you want, by dragging in the yellow edges of the film strip towards the centre (see above).
When you have isolated the part that you want to keep, press the yellow trim button to remove the frames that fall outside of the yellow area. Only ever perform this operation after due care and attention, as the removed frames arc gone forever: there is no 'undo' feature or recycle bin from which they can be retrieved.
Unfortunately that is the full extent of the iPhone's video editing tools; it can't splice together separate parts of a movie, or indeed separate movies altogether, but it still represents an advance over most of its competitors.
Once your movie is edited to your requirements, you can email it, post it to a MobileMe gallery, publish it directly on YouTube or send it to a friend's phone by MMS.
iPhone photo-taking tips
The iPhone, like all modern mobiles, incorporates a camera. Many expected it to be an ultra-high-resolution device, which for a mobile phone would mean somewhere in the region of live megapixels. However, this leads to problems that include digital noise, where the sensor has been so tightly packed with light-sensitive cells that they arc too small to cope with the amount of light they are receiving, or compression artefacts, where in a device throws away too much information while reducing the file size of each image.
Neither of these would be any good on a device with the prestige - not to mention the price tag — of the iPhone, so it would seem that Apple has compromised by incorporating a two- or three-megapixel camera instead. This still delivers results that are very good when viewed on the iPhone's built-in screen and they can be safely posted on a website for viewing online. The photos will be less good when it comes to printing, however.
Even so, it should be remembered that the camera is a secondary function and is not core to the phone's communications tools. As such, it is not the most developed component, so it should be handled with consideration if you want to get the best results from it. Here, we will take you through the things you need to think about when using a phone's built-in camera to ensure you have the best chance of taking pictures you will be proud to show (or even send) to your friends.
Lighting
The iPhone's built-in sensor is not as sensitive as the one built into your dedicated digital camera. This is true for almost all phone cameras, regardless of how cheap or old they might be. It also has no flash, so you must make sure you are making best use of the available natural or artificial light within your scene.
You must also be wary of the fact that less sensitive sensors prefer longer exposures because they allow more time to sample the light in the scene. This makes the iPhone unsuitable for taking shots of fast-moving subjects in low light. As such, both of these factors must be considered when taking photos. If you have an iPhone 3GS, you should also ensure that you use the tap to focus feature to measure not only distance but also the light in a scene for best results.
Although the iPhone docs not have a tripod-mount point, there arc several things you can do to keep it steady. The first is to ensure you always use two hands when taking a picture, and that you press your elbows into your body to keep your arms steady. This will reduce the likelihood that your phone will move either up and down or from side to side, leaving you to think only about whether it needs shifting backwards or forwards.
You must also try to make sure that your subject remains relatively still in poorly lit situations. The iPhone is, therefore, well suited to taking pictures of static objects or people that you can direct, but less so snapping animals, which arc difficult to photograph even with a good, fast camera.
Take photos in well lit conditions to avoid smeared pictures caused by long exposures.
Composition
There are several basic rules of photographic composition that apply to the iPhone camera just as much as they do to any regular snapper. The most important is the rule of thirds.
This relates to the theory that images are most interesting to the human eye if they are composed with the main subjects positioned at the points where two horizontal and two vertical lines intersect.
When you are framing your picture, visualise the screen split into nine separate squares, like a noughts and crosses board, and try to place the main elements of your pictures, such as people's faces and tall buildings on the corners of the central square, where the dividing lines cross each other.
The same theory should be applied to landscape compositions, where the best result is usually obtained by positioning the dividing line between land and sky either one-third up from the bottom of the frame or one-third down from the top.
However, as with all rules, there are times when you might want to break this for maximum effect — for example, putting your subject in the very centre of the image can be an equally striking treatment, in some instances. You should, therefore, read every situation as you find it and not stick rigidly to the rules when they may be inappropriate.
Avoiding chromatic aberration
Cameras are far more dependent on the lens in front of the sensor than they are on the sensor itself, as this has to focus all of the incoming light on a single sharp point. However, the visible spectrum is made up of a vast range of tones that extend beyond what the human eye can see in both directions. By passing plain white light such as sunlight, through a prism, you can see each of these tones split out like the stripes in a rainbow. It looks very pretty on a window sill, but is not exactly what you want to see in your photos.
Chromatic aberration can occur in images with strong contrast between areas of light and dark.
Unfortunately, even expensive lenses can sometimes have trouble focusing all of those tones in a single point, and sometimes you will find that reds, purples and blues may shift slightly from the rest of the spectrum at points of high contrasts. This can manifest itself as a purplish fringe around the edge of the darker subject, and spoils what should be a crisp result. As such, you should, wherever possible, try to take pictures of evenly-lit scenes, and avoid very strong contrasts, particularly where the contrasting item is narrow and would display these fringes on both edges, in which case they may appear to almost double the size of the object itself.
Framing for the iPhone
Notice how your natural instinct when using the iPhone camera is to turn it through 90° so that the shutter button is below either your left or right thumb. This makes the iPhone one of the best cameras for left-handed users, because most are only ever built with right-handed users in mind.
However, while it may work quite happily in three different orientations, the iPhone is a fundamentally portrait-orientated device, because that is how it fits best in the palm of your hand. As such, when taking pictures for use as a background graphic on your login screen, you should try to take them with portrait orientation.
Further, we would advise against taking pictures of subjects with strong contrasts for use as a graphic on your login screen, because these can make pincode screens more difficult to see quickly.
Setting background images
Once you have taken the image that you would like to use as your login screen background, navigate to the Photos application and open the image. Tap the left-most icon on the toolbar at the bottom of the scrccn (it looks like a box with an arrow shooting out of it) to call up the Options menu. This lets you email it (using your default email address), attach it to a contact in your address book, post it to the web or use it as wallpaper. It is this last option that you are after.
Tap it and use finger gestures to trim it down to just the portion you want to use (start with your fingers together and open them up to zoom in, then drag the image to re-centre it), and then tap Set Wallpaper to save it to the login screen.
The iPhone contact application enables you to add a photo to a contact so it will be displayed along with their record {right).
Assuming your contact already has an entry in your address book, open it and tap the Edit button. If you have not given that contact a photo identifier already, you will see an empty square with the words Add Photo in the top-left corner. Tap this and you will be given the option of selecting a photo you have taken already, or snapping a new one. Tap Choose Existing Photo and it will open your Photo Albums, allowing you to navigate to the picture you want to use.
If the photo is not well framed, don't worry. You can now use finger gestures to enlarge the image so that it only shows the part of the picture you want to use, before clicking on Set Photo to drop the resulting image into the empty box on their details. Tapping it again will let you go back in and re-crop the picture if appropriate.
Maximum resolution for printing
The maximum size at which you can print photos taken using your iPhone depends on the level of quality you want to maintain. The iPhone 3G's camera's native two-megapixel resolution equates to a little over 1,600 x 1,200 pixels. To obtain the highest possible quality from printed images, you should aim for a print resolution of 300 pixels per inch of paper. This means, in practice, a print size of about 5 x 4in.
Accepted wisdom states that for most people a resolution of about 150dpi is adequate when viewed at arm's length, so you may get away with doubling this size if you arc willing to make compromises.
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