A histogram is a graph that displays how light is distributed in your picture. The left side of the graph represents the shadows, while the highlights are on the right. This means that if the histogram has a high peak on the left, you can tell that a lot of pixels in the picture are dark, or in shadow. A peak on the right of the graph means that a lot of pixels are bright, or in highlights. Peaks in the middle of the graph represent pixels in the midtones of your exposure. Often it’s difficult to tell if your photograph is correctly exposed by looking at the image on the back of the camera particularly in bright light. I set my camera display so that I can see an image thumbnail as well as the histogram.
 

The Histogram of a Good Photo.
Let’s look at some examples of histograms. Refer to the picture below. On both the left side and the right side of the graph, you can see that there are no high peaks. This kind of histogram tells you that no part of the scene is over or underexposed. Ideally the graph information should fit within the left and the right hand side. 

The Histogram of an Underexposed Photo.
Below is a the histogram of an underexposed photo. You can see a spike in the shadows that starts with a peak on the left of the graph. That means that the picture has lost data in the shadows. There’s also just a few pixels trailing off the right side of the graph, so a tiny bit of data might have been lost there as well. Skin tones suffer particularly when an image is underexposed. To move the histogram over to the right and get a better exposure use the camera’s exposure compensation, and overexpose the photo until the graph fits within the left and right sides.
 

The Histogram of an Overexposed Photo.
Here you can see a pronounced spike on the right side of the graph. You’ll note that the height of the peaks is somewhat low in this picture; that’s not an indication of under or overexposure, it’s a measure of the spead of tones from absolute black on the left to absolute white on the right. All you need to worry about is whether they breach the left or right edges of the histogram.
 

 When composing your photo always try to avoid the histogram from spiking at either extreme end of the graph, where you’ll lose data and have under or overexposed parts of your picture. It’s important to make sure your image is correctly exposed at the time you take the photo as although you can fix minor over and underexposure problems by shooting in RAW, it’s often impossible to correct overexposed highlights.

Spring and Autumn are my favourite seasons for taking photographs, in spring I feel more invigorated after the winter and more inclined to get out and take new photos.
Here are a few of my tips for taking photographs in spring.

Landscapes:
Spring landscapes are colourful and the new spring growth looks great against against a blue sky. To make the colours more saturated, particularly the blue sky, fit a polarising filter. Look out symetrical shapes and unusual views such as rows of strong green vegetation or views through tree blossom. Try and frame your landscapes with tree branches, doorways, arches window frames etc etc. If you have a wide angled lens take it out of hibernation and use it to incorporate a foreground view as well as the landscape in the distance. Don’t forget about your depth of field to get everything in focus, use a higher f number such as 11 or 22.

Sunrise and Sunset
Take advantage of the sunrise now the days are getting longer. The air is cleaner at sunrise and at this time of year where day and night temperatures vary a lot the colours will photograph very differently early in the morning than they will late in the afternoon. Fog and mist can also be an extra bonus. Try getting up high, the tops of hills or mountains are a perfect as they give you great views over valleys which may hold early morning mist and fog like a bowl. A polariser can also help here, and also remember that fog acts like a soft box and can lower the contrast of your surroundings which can leave you with rather long exposure times so take a tripod if you have one. Your camera may also have a few exposure problems and as a result, you’ll have to use + exposure compensation to rectify this. If your skies end up looking a little washed out try fitting a neutral density grey graduated filter.

People
Although the days are getting longer the sun is still low in the sky and this can create problems with heavily backlit scenes. Rather than photographing your subject with their back to the sun try photographing them with the sun to one side but still slightly behind them, or photograph them in the shade under a tree and use your flash to fill in. Try using a low f number on your lens to throw the background out of focus, this will also help to bring the shutter speed up to prevent camera shake if the light is too low.

Flowers and Blossom
Try and look for patterns and look for the abstract when photographing flowers and blossom. Get down low and zoom right into the subject or use a wider angle lens and very little depth of field around 5.6. Try and break the rules also, flowers look great with the sun behind them. Be very wary of underexposing if you’re looking into the sun, you make have to use your exposure compensation +1 or +2

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Most camera and imaging software has some means of doing this, but whatever you do DONT ALLOW YOUR CAMERA TO CHANGE YOUR IMAGES INTO BLACK AND WHITE – DO IT LATER! It is always better to manipulate your photos using photoshop or your bundled camera’s software because you can’t change or go back to the original image if the camera has made any changes, and image manipulating software is much better and more subtle than anything the camera can do.

So here is how I change a colour image into Black and White. I use adjustment layers in photoshop. It’s very easy and quick.

Step 1: Open up a colour image in Photoshop and make sure you have your layers pallet visible. If it isn’t visible just click on the window menu in Photoshop and select the layers option.

Step 2: Next we will create a Hue/Saturation adjustment layer. To create this layer just click the button on the very bottom of the layers pallet that looks like a circle that is half black and half white. Then select the Hue/Saturation item.

Step 3: Now you will see a dialog box with sliders for hue saturation and lightness. For now we will leave all of those settings alone and just click OK. You will notice there is a new layer in the layers pallet.

Step 4: Now create another hue saturation adjustment layer the same way we just did, only this time when the dialog box opens adjust the saturation slider all the way to the left. You should notice your image has turned black and white. Click ok. Now there should be a total of three layers in the layers pallet.

Step 5: Select the middle layer clicking on it once. Now we need to change this middle layer’s blending mode to Colour. To change the blending mode look near the top of the layers pallet for a little drop down menu that currently says “normal” click on this menu and select the “color” option near the bottom of the list.

Step 6: Now if you look at the layers pallet you should notice that the middle layer is split into two sections, the one on the right should be a box that is just white. The one on the left looks like a bunch vertical of grey smudges with a slider below it. Double click the left and the hue saturation dialog box should come up. Now the fun bit. Try sliding the hue slider around and watch your image. Your image should be changing. Some parts will get lighter while others will get darker. This works by changing what colours Photoshop sees as black and which is sees as white. When you have found a setting you like for the hue slider, try adjusting the saturation slider to fine tune your image. Click ok when you are happy with your image. The good thing about using adjustment layers is your original image is still sitting untouched under the two adjustment layers and you can get back to it deleting or hiding the other two layers.

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Holiday time is almost upon us and there are two things you need to think about before you pack up your cameras and head off to the great outdoors:
Memory!!! Back up your hard drive, and format your memory cards properly.

One thing I talk more about than anything else to students and fellow photographers is the importance of backing up your hard drive and how to handle your memory cards. I think I have said once or twice that you haven’t become serious photographer until you’ve lost your photos on a memory card or had your hard drive fail.

Losing data happens to just about everyone. And once it has happened to you it rarely happens again. With memory cards, particularly with the more expensive ones you can easily install photo-rescue software that usually will locate and restore pictures that get lost on a memory card, and if you back up your hard drive regularly you won’t loose everything.

Note that I said “usually.” There are no guarantees in memory card photo rescues. But there are several ways to boost your chances of success.

1. Always carry spare memory cards. If one starts giving you trouble, put it in your pocket, away from the other cards, and use another one. Once you’ve transferred the data from the dodgy card to your pc throw the card away. In my experience memory cards that start giving you problems can’t be trusted in the future.

2. Once you have transferred your images to your pc and backed them up format the card.

3. Blank memory cards that act up should be reformatted in your camera. (Use the camera’s menus. Look for “format.”) Then try them again. If they still give you trouble throw them away, memory is cheap enough these days to buy a new card.

3. Always reformat your memory cards before using them again. Don’t just erase your pictures. Continual erasing is the main reason memory cards go bad. Reformatting gives them a clean start.

4. Never allow any software of any kind to erase photos as they are transferred to your computer. Keep the pictures on the memory card until you have seen all of them on your computer.

5. Don’t do ANYTHING to the bad card. Don’t try to read it again from your camera and don’t try to store another photo on it. You’ll need to put the bad card into your card reader – not from the camera, and run your photo-rescue software.

6. For all of our commercial work we use cards that are no larger than 2GB. The reason for this is that if the card fails or a camera is lost or stolen with a card in it I won’t loose all of my images. Buy 4 x 2GB cards rather than an 8GB card. Also keep the cards in the plastic covers they come with, grains of sand and fluff can ruin cards.

If your memory card fails and you can’t get your images from it here are my choices for memory card rescue software:

For Windows, I recommend MJM Data Recovery from www.mjmdatarecovery.co.uk/photos/free-photo-data-recovery-software.html. It’s free.
Note that MJM rescues only JPEGs, the standard photo format. If you need to rescue photos in other formats, try PhotoRescue Wizard PC, from www.datarescue.com/photorescue. It’s about £20. The demo version (free) will rescue up to 10 photos.

For Macs, I recommend the Mac version of the same program. It’s also about £20 and will rescue up to 10 photos without payment. Get it from the same site, www.datarescue.com/photorescue.

And for hard drive backup I use Timemachine for my macs and there are plenty of good applications for pc. A backup takes some time to transfer your files so don’t do it the night before you leave on holiday. The great thing about Timemachine on a mac is that you can go back to the point in time where you lost data and retrieve it without having to bring all of your backed up data across. Go down to pc world or go online and you’ll find an external drive to do the job.

And buy an external hard drive that is larger than your internal hard drive, you’ll be surprised how much memory all that holiday video takes up!

If you are off on holiday in the next couple of weeks I hope you take some great pics, I’m going to run a holiday photography competition in September so bear that in mind!

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1. Clean the lens. Over time the camera lens can get dirty and create a blurred image. Just give it a good wipe.

2. Pick your subject carefully Bearing in mind the usual limitations of camera phones. This means:
Avoid subjects in low light, at least if you want them to be consistently lit. The small sensors in camera phones cannot run at high ISO speeds (i.e. high sensitivity to light, permitting indoor photos without a flash) without introducing large amounts of noise. In most circumstances, this makes indoor photos other than in the best-lit places difficult.

Avoid bright reflections, and other “hot-spots”. This will either force the camera to under-expose the rest of the shot, or cause the camera to blow out the highlights on the brightest parts of the shot. The latter is worse, since it is sometimes possible to extract details from parts of the image that are too dark, but impossible to recover blown highlights (since there is no detail to extract). On the other hand, this can be used to artistic ends, such as with bright light streaming through a window.

Avoid anything that requires tight focusing. Due to their very short focal lengths (the distance between a camera’s optical elements and the sensor, again, owing to their small sensors), camera phones excel at shots where nearly all of a scene is in focus. However, this (and their typically weak auto-focus mechanisms) usually precludes focusing on objects very close to the phone, or having a very shallow depth of field to get a blurred background effect (this be faked in software later anyway).

Avoid “mirror shots”, as well as arm-length shots taken by yourself. Aside from them being clichèd, they require taking photos indoors and mirrors also often end up confusing auto-focus mechanisms. Get outside and get someone to take the photo for you. If you’d rather take the picture yourself, most camera phones have an auto-timer feature so you can set the phone somewhere and get into frame.

3. Set your phone to its highest picture quality and resolution. You might end up taking a good enough shot that you want to print it out; you won’t be able to do this if you only have a low-resolution version of the photo.

4. Turn off picture frames. A normally great shot may be ruined by a cheesy frame or background; if you really must have one, add the frame afterwards.

5. Turn off any other effects. These include black-and-white, sepia tones, inverted colours, and so on. These aren’t as necessarily as cheesy-looking as frames and have their place; nonetheless, these things are much better done in photo editing software afterwards than on board the phone. You may find, for example, that when you view your photo on a large screen that the colours in your scene are far too good to lose to black-and-white.

6. Set the white balance, if your phone supports it. The human eye usually adjusts for lighting, and so white appears white in any kind of lighting. A camera, however, will see that a given subject is redder than normal under normal incandescent household lighting. Better camera phones will give you the option to adjust the camera for this. If you have such an option, use it. If you’re not sure what setting to use, experiment.

7. Use your flash judiciously. If you find yourself using a flash because your whole scene is insufficiently lit, you’re probably taking photographs indoors in poor light. Don’t do this, a scene lit entirely by your flash will look unnatural, since on a camera phone it is not typically possible to aim the flash anything but directly ahead (i.e. you can’t bounce it off ceilings or walls, as with dedicated flash guns for SLR cameras). On the other hand, a flash is a good option for filling in shadows in harsh sunlight.

8. Frame your shot. Make sure that everything you want in the shot is in the picture, and ready to be captured. Some phones show the entire viewfinder, meaning that what is on the screen is exactly what will be captured in the image. Other phones, however, only show what is in the middle of the image, but will capture more than the viewfinder shows. It’s better too much empty space into your picture; you can always crop it later.

9. Finally, take the picture. Keep your hand steady as you press the shutter button. After you take the picture, keep the phone in position to allow the picture to be recorded. If you move immediately after pressing the shutter button you will just get a blur!

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2. Make your own shade
If your subject is not movable (for example if you’re shooting macro with a flower) create your own shade. Use your own shadow, the shadow of someone else or bring an object with you (like an umbrella, a reflector or large sheet of card) to block out the sun.

3. Use Fill in Flash
Most of us were trained to put the sun behind you when taking a photograph so that your subject will be well lit. Shooting into the sun may lead to lens flare or a dark subject – but at times it can improve it drastically – particularly if you use a flash to fill in the shadows that are created by doing so.

4. Use a Reflector
Another way to fill in the shadows caused by direct sunlight is to use a reflector. These bounce light up into the face of your subject and are great because they allow you to shoot into the sun – as with when you’re using fill in flash.

5. Change Your Perspective
Sometimes moving your subject isn’t possible – but moving around it can give a different impact. This might be moving to the other side of the object, shooting from directly above or even getting down low and shooting up. Doing so will change the angle of the sun hitting both your subject and the camera and give your image a completely different feel.

6. Use a Lens Hood
Suffering from lens flare? If your lens came with a lens hood – get it out and use it. If you don’t have one – it’s not difficult to construct one out of card – or to even use your hand to shield your lens from the sun. Just make sure that your shot is free of your hand or the DIY hood that you’re using.

7. Filters
Sometimes a filter can be handy when shooting in bright sunlight. I try to take a Polarising or Neutral Density (ND) filter with me at all times. The polarising filter will help cut down on reflections and both will cut down the light getting into your camera to let you use slower shutter speeds and smaller apertures if you’re looking for more control over these elements of exposure. Polarising filters have the added bonus of giving you some control over some colours – particularly when you’ve got reflection on water and blue sky with fluffy clouds in your shot.

8. Play with White Balance Settings
Many digital cameras come with the ability to choose different white balance settings. While you can make adjustments later on post processing (particularly when shooting in RAW) choosing the right setting at the time of shooting can be worth experimenting with. I personally shoot in RAW and do this later on my computer.

9. Metering
Direct sunlight makes correct metering tricky. In these conditions I generally choose spot metering mode on my DSLR and choose the main subject of the scene that I’m photographing (the focal point) to meter off. Alternatively pick a mid-tone area to meter off if you want everything to be exposed relatively well. Check your shots immediately to see if you need to adjust your technique (your histogram can be handy here) and if you have time – take multiple shots metering off different parts of the scene so that you can choose the best one later.

10. Pick The Time of Day to Shoot.
For many of us we won’t have the luxury of sitting all day long waiting for the perfect light – but if you do, the time of day can dramatically impact your shot. Dawn and Dusk are particularly good times to shoot as the direction and colour of the light is often more useable than the direct overhead light at midday.

11. Shoot Silhouettes
If the bright light of the Sun is causing you a problem – why not use it to your advantage and make your subject into a Silhouette.

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You don’t always need to set your camera to ‘full manual setting’ to make changes to the camera auto settings, I’ll talk about this at the end of this piece but first I need to get the tech stuff out of they way.

Aperture Size.
The size of the aperture determines how much light passes through your lens, large apertures let more light pass through, small apertures let less light pass through.
Aperture settings are referred to as f-stops, or f-numbers, expressed as a fraction, such as f/22. However, to save space, f-numbers are often denoted by just their denominator, such as 22. Note, the larger the f-number, the smaller the relative aperture.
On a manual camera, f-numbers are usually adjusted with a ring outside your lens barrel. A typical sequence of f-numbers on a camera run, from largest to smallest aperture: 1.8, 2.8, 4, 5.6, 8, 11, 16, 22.
The difference between each f-number is twice the amount of light. So, aperture setting f/16 lets in twice as much light as f/22.
The aperture size determines the depth of field, or zone of sharp focus, that surounds your subject: whereas small apertures (high f-numbers) produce a long depth of field, large apertures (small f-numbers) produce a short depth of field. Therefore, if you’re taking a picture of a landscape, and you want both foreground and background to be in focus, use a small aperture such as f/16. On the other hand, if you’re taking a picture of a friend or family member, and you want to place more emphasis on them by blurring the background, use a large aperture such as f/4.

Shutter Speed.
Release the shutter, you will see the aperture momentarily open for the length of time set by the shutter speed.
The shutter speed determines how long your film/digital sensor is exposed to light passing through the aperture: the slower the shutter speed, the longer the shutter remains open, the more light reaches your film/digital sensor. So, both aperture size and shutter speed determine the final exposure of your picture.
Like f-numbers, shutter speeds are expressed as a fraction, such as 1/60 second. However, to save space, shutter speeds are often denoted by just their denominator, such as 60. The larger the shutter speed number, the shorter the amount of time your film/digital sensor is exposed to light.
On manual cameras, the shutter speed is usually adjusted by a circular control knob on top of the camera. A typical sequence of shutter speeds on a camera run, from slowest to fastest: 1, 2, 4, 8, 15, 30, 60, 125, 250, 500, 1000.
The shutter speed determines the amount of motion blur a moving object will have in your final picture. Use a fast shutter speed (such as 1/500 sec) to freeze fast moving objects in their trajectory, or use a slow shutter speed (such as 1/2 sec) to illustrate movement by creating motion blur.
Like f-numbers, the difference between each shutter speed setting is twice the amount of light. For example, shutter speed 1/60 sec lets in twice as much light as 1/125 sec.
Due to the doubling/halving nature of both aperture and shutter settings, closing the aperture one stop (halving the light) while simultaneously decreasing the shutter speed by one setting (doubling the light) produces no effective change in the amount of light reaching your film/digital sensor. The same is true for closing the aperture two stops while decreasing the shutter speed by two settings. This means there are several aperture and shutter settings which produce the same overall exposure of your final picture. For example, the combination f/4 and 1/60 sec produces the same overall exposure as f/2.8 and 1/125 sec, or f/5.6 and 1/30 sec. This is not to say these settings will produce the same final picture since the combination you choose will determine the depth of field surrounding your subject (aperture size) and the amount of motion blur of moving objects (shutter speed).

Exposure Meter.
Most camera light meters estimate the exposure of your final snapshot by a “center-weighted” averaging algorithm, more sophisticated DSLR cameras can also meter ‘Spot” or very small parts of the subject, and ‘Evaluative’ which can cope with backlit subjects.
One condition that often “fools” the light meter is when a subject is backlit or the sun is shining behind your subject. You can tell if the meter has been fooled if your subject is underexposed.
For the same reason, a dark or black object occupying the center of the viewfinder will also “fool” the light meter. You can tell here if the meter has been fooled if your subject is overexposed.
Objects of average light intensity are grey stone, weathered wood, foliage or dark skin.

How to fix over or underexposure.
There are a number of techniques you can use to fix over or under exposure. There are two I use most often.
1. If you have your camera set to Av (aperture priority) or Tv (speed or time priority) you can take control yourself quickly by telling your camera to overexpose or underexpose by moving the exposure slider on your LCD panel to plus or minus. Normally one or two stops will fix your image. If your camera is set to Av you will adjust the shutter speed, if it is set to Tv you will adjust the aperture.

2. Set your camera to manual. Now you have control over both aperture and shutter speed. The camera’s light meter will still tell you what it thinks the ideal exposure should be, and as you adjust both the speed and the aperture the camera will tell you whether you are over or underexposing. When you first try this out it’s a good idea to put your camera on a tripod as there are so many things to think about, and if the camera is not moving around you’ll see how your adjustments are affecting your image.

Practice makes perfect and as usual my advice is to take lots and lots of pictures, be adventurous, and don’t worry if you find it confusing to begin with.

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One metaphor often used is to imagine your camera is like a window with shutters that open and close. Aperture is the size of the window. If it’s bigger more light gets through and the room is brighter. Shutter Speed is the amount of time that the shutters of the window are open. The longer you leave them open the more that comes in.
Now imagine that you’re inside the room and are wearing sunglasses, your eyes become desensitized to the light that comes in (it’s like a low ISO).There are a number of ways of increasing the amount of light in the room, or at least how much it seems that there is. You could increase the time that the shutters are open (decrease shutter speed), you could increase the size of the window (increase aperture) or you could take off your sunglasses (make the ISO larger).

How does your camera know what the perfect exposure is? Your camera is pre programmed by the manufacturer to let an exact amount of light in for the perfect exposure, which is 18% of the light reflected form a grey surface.

Shutter Speed:
Shutter speed is measured in seconds – or in most cases fractions of seconds. The bigger the denominator the faster the speed (ie1/1000 is much faster than 1/30).
In most cases you’ll probably be using shutter speeds of 1/60th of a second or faster. This is because anything slower than this is very difficult to use without getting camera shake. Camera shake is when your camera is moving while the shutter is open and results in blur in your photos.
If you’re using a slow shutter speed (anything slower than 1/60) you will need to either use a tripod or some some type of image stabilization (more and more cameras are coming with this built in).

Shutter speeds available to you on your camera will usually double (approximately) with each setting. As a result you’ll usually have the options for the following shutter speeds – 1/500, 1/250, 1/125, 1/60, 1/30, 1/15, 1/8 etc. This ‘doubling’ is handy to keep in mind as aperture settings also double the amount of light that is let in – as a result increasing shutter speed by one stop and decreasing aperture by one stop should give you similar exposure levels.

Some cameras also give you the option for very slow shutter speeds that are not fractions of seconds but are measured in seconds (for example 1 second, 10 seconds, 30 seconds etc). These are used in very low light situations, when you’re going after special effects and/or when you’re trying to capture a lot of movement in a shot). Some cameras also give you the option to shoot in ‘B’ (or ‘Bulb’) mode. Bulb mode lets you keep the shutter open for as long as you hold it down.

When considering what shutter speed to use in an image you should always ask yourself whether anything in your scene is moving and how you’d like to capture that movement. If there is movement in your scene you have the choice of either freezing the movement (so it looks still) or letting the moving object intentionally blur (giving it a sense of movement).

To freeze movement in an image you’ll want to choose a fast shutter speed and to let the movement blur you’ll want to choose a slower shutter speed. The actual speeds you should choose will vary depending upon the speed of the subject in your shot and how much you want it to be blurred.

Use motion to your advantage. For example when you’re taking a photo of a waterfall and want to show how fast the water is flowing, or when you’re taking a shot of a racing car and want to give it a feeling of speed, or when you’re taking a shot of a star scape and want to show how the stars move over a longer period of time etc. In all of these instances choose a longer shutter speed. However in all of these cases you need to use a tripod or you’ll run the risk of ruining the shots by adding camera movement.
Focal Length and Shutter Speed – another thing to consider when choosing shutter speed is the focal length of the lens you’re using. Longer focal lengths will accentuate the amount of camera shake you have and so you’ll need to choose a faster shutter speed (unless you have image stabilization in your lens or camera). The ‘rule’ of thumb to use with focal length in non image stabilized situations is to choose a shutter speed with a denominator that is larger than the focal length of the lens. For example if you have a lens that is 50mm 1/60th is probably ok but if you have a 200mm lens you’ll probably want to shoot at around 1/250.

What is Aperture?
Put most simply – Aperture is ‘the size of the opening in the lens when a picture is taken.’
When you hit the shutter release button of your camera a hole opens up that allows your cameras image sensor to catch a glimpse of the scene you’re wanting to capture. The aperture that you set impacts the size of that hole. The larger the hole the more light that gets in – the smaller the hole the less light.

Aperture is measured in ‘f-stops’ for example f/2.8, f/4, f/5.6,f/8,f/22 etc. Moving from one f-stop to the next doubles or halves the size of the amount of opening in your lens (and the amount of light getting through). Keep in mind that a change in shutter speed from one stop to the next doubles or halves the amount of light that gets in also – this means if you increase one and decrease the other you let the same amount of light in – very handy to keep in mind).
One thing that causes a lot of new photographers confusion is that large apertures (where lots of light gets through) are given f/stop smaller numbers and smaller apertures (where less light gets through) have larger f-stop numbers. So f/2.8 is in fact a much larger aperture than f/22. It seems the wrong way around but you’ll get the hang of it.

Depth of Field and Aperture
Depth of Field (DOF) is that amount of your shot that will be in focus. Large depth of field means that most of your image will be in focus whether it’s close to your camera or far away.
Small (or shallow) depth of field means that only part of the image will be in focus and the rest will be fuzzy. Aperture has a big impact upon depth of field. Large aperture (remember it’s a smaller number) will decrease depth of field while small aperture (larger numbers) will give you larger depth of field.
It can be a little confusing at first but the way I remember it is that small numbers mean small DOF and large numbers mean large DOF.

The best way to get your head around aperture is to take lots of photos and experiment. Set up a shot outside and place some items near the camera as well as far away and take a series of shots with different aperture settings from the smallest setting to the largest. You’ll quickly see the impact that it can have and the usefulness of being able to control aperture.

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So when and why should you use the zoom lens on your camera?
One of the most important rules with portrait photography is “get close”. Unfortunately, for most family snaps, that rule is rarely applied. Uncluttered, closely cropped shots make the best family snaps and natural portrait photographs, and a zoom lens is the ideal way to get close in and get the cropping right.

What does using a zoom do for your photograph?
A zoom lens will get you physically closer to the action, and the content of your photograph will be much stronger if you are be able to isolate parts of the action.
Depth of field can also be used to your advantage when using a zoom lens particularly in portraits. Keep the aperture at around f5.6 and focus on the subject, when the lens is wide open you’ll get the subject in focus and the foreground and background out of focus giving you much stronger emphasis on the subject.
A mid range zoom lens is also ideal for travelling. My wife has banned me from taking a tripod and sets of lenses on holiday so I take a 24mm-105mm lens which can deal with most situations. If you can get away with taking another zoom with you take a 70mm-200mm or something up to 300mm or 400mm. Photographing the locals without attracting attention to yourself is much easier with a longer zoom lens.

Optical Zoom and Digital Zoom?
If you are about to buy a camera, perhaps even step into the world of digital, buy a camera with the strongest optical zoom you can afford. Some of the digital cameras available today have zoom lenses that are 10x or even stronger! The higher the number represented in the optical zoom the closer you can get to the action and the more dynamic your pictures can be. 
As for digital zoom, well…that is another thing altogether. Digital zooms are available in many digital cameras and work on a similar principle to cropping in on a negative. Digital zoom crops in on the digital image and uses only the central pixels in the picture. Then, using inbuilt software, the image is enhanced and built into a file that can be printed. However, the sharpness of your pictures suffers and should only be used if your desperate, if at all. Don’t factor the digital zoom into your purchasing decision.

The Great All-Rounders
Advancements in lens technologies have made some lenses possible today that just couldn’t have been considered twenty years ago. Today, you can buy one lens that lets you take wide angle landscapes and then zoom in to a person in that landscape. What’s more, these lenses are incredibly sharp! Lenses like the Tamron 18-250mm for digital SLR cameras are fantastic and you could travel the world with only this lens and hardly ever miss a shot. In fact, Tamron are packaging their 11-18mm and their 18-250mm lenses together now so that you are covered from superwide to supertelephoto in only two lenses. Most high end lenses also have an image stabilisation capability which can really help with blurred photographs resulting from camera shake.
Compact digital cameras are also including lenses that do much the same thing. The Ricoh R7 has a 7x zoom. The Canon PowerShot is similar. The SX100 IS has a 10x zoom. And there are many others like these. Included with these kinds of cameras are vibration reduction and anti shake modes that prevent your telephoto pictures from being blurred from camera shake.

How Close is ‘Close’?
If you don’t know just how close to get, try this. Compose your picture as you normally would and take it. Then, zoom in. Then, zoom in some more. Keep zooming, or moving closer until you actually begin to see only what you need to see and no more. Take another picture and compare the two. Almost invariably, your second picture will be the more interesting and dynamic of the two.

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Photo Printers use either Dye based Inks or Pigment Inks.
Epson was the first company to ship a printer based that used pigment inks, which are made up of tiny, encapsulated particles that sit on top of the paper, instead of being absorbed into a paper’s fibers, which is what happens with dyes.
The most important reasons for using pigment inks are archival print life and color stability. The dye inks used in most early inkjet printers exhibited signs of fading or shifts in color after a short period of time (as quickly as days, in some cases). As a result, the graphic art and fine art markets turned to pigment inks. Pigment inks are much more stable and can last more than 200 years on some paper types under ideal (museum-quality lighting and framing) conditions.

The Paper you use is as important as the ink in measuring print life. Glossy papers, with their slick finishes, are usually the worst offenders in terms of print life, but any paper with so-called optical brighteners—used to make a paper’s finish bright, bright white—will have some issues with either ultraviolet light or atmospheric pollutants , like ozone, which can quickly break down dye inks on unprotected prints. It’s usually best to use paper produced by the same company that manufactured the printer. Remember printer companies make their money from selling you the ink and paper rather than the printer itself. You may think the printer is cheap but you’ll be surprised how expensive running it is.

Pigment inks aren’t perfect—they’re generally more expensive than dye inks, and they don’t have the brightness and broad color range (or gamut) that dye inks have. And, most printer manufacturers continue to push the print longevity of dye inks. Many dye-based prints, kept under glass and away from direct light, can last for up to 25 or 30 years, which is more than adequate for most of us. But some tests show that some dye/paper combinations show archival life of nearly 100 years, that’s the primary reason why dye printers aren’t going away any time soon.

Another problem that some early pigment inks had was a phenomenon called metamerism, which is essentially the human eye detecting a shift in color when viewing a print under different light sources. For example, an image might look normal under fluorescent light, but exhibit a greenish color cast when viewed outside in bright daylight or under a reading lamp. Metamerism plagued the first generation of pigment inks, but Epson, who pioneered pigment inks as a mainstream technology, worked extensively to reduce this (through more chemistry than I need to know about), and companies like Canon and HP are reaping the benefits of Epson’s initial forays into this market.

Custom inks
In addition to the big three printer manufacturers, a small cottage industry composed of third-party vendors has arisen that provides custom ink sets. I’m not talking about the low-cost cartridge-refilling companies; I’m referring to companies who have created a wide range of pigment ink sets that work in commercial printers and provide even greater tonal range for specific printing needs, most commonly (but not limited to) black and white images, especially some of the split-toning methods that originated in the darkroom. Cone, for example were one of the first companies to use quadtone black inks, four black inks of varying densities that produced truly neutral (or custom-toned) monochrome prints of stunning quality.

The bottom line
When thinking about why you would want a more expensive, pigment-based printer and specialized papers, there is one compelling reason: money. If you are a photographer or an artist looking to sell your work, the stability and longevity of pigment-ink-based prints means that you can do so without worrying about a buyer coming back in a year complaining that your print has yellowed or turned green. Remember also to choose good quality paper.
I’ve used printers from all the big manufacturers over the years but having spent many years producing traditional wet process prints I have to say I’ve always been disappointed with the results from a desktop printer. I use my local pro lab for all my printing, I find that you still can’t beat a print produced in a lab or print produced using traditional wet process techniques, particularly with black and white. Short runs of colour prints (under 5) are cheaper to do at home than at your local pro lab. But I think it’s cheaper to do a run of 20 A4 prints at your local pro lab than it is to do it at home.

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