It seems hardly a day goes by without some new mobile phone manufacturer cramming a few more pixels into their phones. It could seem as if the whole world is shifting towards a mobile phone camera future. But is it really? Do mobile phone cameras tick your boxes?

Personally I like and loathe the iPhone camera in equal measure. I have some photo apps that I enjoy using and get some interesting results from, but at only 2megapixels (and not goood pixels at that) the quality is really quite dire. Would a 10-20-30megapixel cameraphone change my mind? Unlikely because I still like the act of holding a proper camera and being able to change lenses to suit my needs, but maybe I'm just a traditionalist - some may even call me luddite, although sitting here typing this blog on a computer, with a wireless keyboard would possibly suggest otherwise...

However, with news agencies happy to accept images and footage from mobile phone cameras so they can be the first with the 'big scoop' and make use of the citizen journalist, the market might need to at least take a look. Not only that, but technology is marching forwards relentlessly as it usually does.

At some point in the future we'll be using liquid lenses, focused by electrical charges that change the shape to affect focus and focal length, and smaller than a pancake lens but with the focal length of a super-telephoto. In short, they'll able to do all that we can do with a big bag full of lenses. So where does it stop? Do we quietly accept the rise of the mobile phone camera or are we too wedded to our ideals of photography and the layout of the 35mm format that hasn't really changed in any great way at least since Canon introduced the Canon Flex - their first SLR - 50 years ago. 

What are your thoughts? Would you use a mobile phone camera if it could give you the same results as your SLR or do you still like the act of changing lenses, using a viewfinder and having buttons and dials to press and turn?

If you use one of the consumer cameras, from the EOS 50D down, you may well have come across the A-DEP mode. But what does it do and how does it work?

 A-DEP stands for Auto Depth [of field] and it aims to give you enough depth of field in your image for the subjects you want to capture. It's most used for landscapes as this is where you most commonly want lots of depth of field. 

In A-DEP mode, the camera evaluates the scene and uses the focus points to determine the nearest and farthest subjects. One thing you need to be aware of is that it only picks up subjects under the focusing points - it won't find a subject not covered by them.

By calculating the distance from the nearest to farthest points, the camera can calculate a point to focus on and an aperture to use to give you enough depth of field to ensure they are all in focus. With this done it works out a shutter speed to use to give the correct exposure and you're ready to shoot. 

It's not a widley used mode really and for many, it is seen as a shortcut for those that don't yet understand the relationship between aperture, subject distance and depth of field, but if you're shooting a landscape it's worth experimenting with, even in conjunction with your normal method of shooting, just to see ther results. 

If asked the question above, what would you say the answer is? Is it:
a) A lens with a focal length greater than 200mm?
b) A lens which can change it's focal length?
c) A lens whose physical length is less than the focal length?

I expect most of you will go for answer "A" but you'd be wrong. In real terms, anything with a focal length over 200mm is termed a telephoto lens in common parlance...but, there is a clue in the fact that you often find lenses shorter than 200mm refered to as telelphotos. So what are they talking about? Well, the answer lies in techie talk. According to the Canon Lens Work book, a telephoto lens is defined as follows:
With general photographic lenses, the overall length of a lens (the distance from the apex of the front lens element to the focal plane) is longer than its focal length. This is not usually the case with lenses of particularly long focal length, however, since using a normal lens construction would result in a very large unwieldy lens. To keep the size of such a lens manageable while still providing a long focal length, a concave (negative) lens assembly is placed behind the main convex (positive) lens which is shorter than its focal length. Lenses of this type are called telephoto lenses. In a telephoto lens, the second principal point is located in front of the frontmost lens element.

Translated into simple terms, a telephoto lens is one that has a physical length (from the front lens element to the the focal plane) which is less than its stated focal length.