What are megapixels?
Today it would be challenging to find someone or a company who doesn’t put megapixels as a key selling point for their product. Too often however this is a confusing and inaccurate way to measure the real quality of the camera and its ability to take high quality images. Why? Well let’s try to understand this in a simple way.
A megapixel is 1 million pixels. These are tiny squares that when put together create your image. The resolution of your image therefore will be determined by how many of these tiny squares are packed together in a small area.
Therefore a 41Mp camera will have around 41 million tiny squares of information per inch such as the Nokia Lumia 1020.
Surely that is a good thing? That’s more an a Nikon D800!
Yes and no. This purely depends on whether you are using a smart phone or a DSLR. For purposes here we will discuss Smart Phones vs DSLR.
Yes because the information there more complete an image you will generate. You may have had a 1.2Mp camera in the past and when you zoomed in to you it would become pixelated quickly
No because having too many megapixels can negatively impact the overall image quality. Most smart phones carry small sensors this therefore means that the pixels themselves will have to be even smaller and consequently you have overcrowding. It’s similar to packing in 1000 people in to a room designed for 100. Whilst you might be able to do this it will ultimately lead to severe overcrowding and much higher levels of noise thus reducing the quality of the image. You will not face this challenge with a DSLR. With a larger sensor you allow a greater area for the light to fall on and as a result you take a much more accurate image- even if the megapixel count might be lower. Unless you’re planning on printing your images in magazines, billboards or for television it is really will not matter if you use a compact or smart phone between 8MP and 100MP.
The other issue with a large number of megapixels is that if you choose to share your photo online e.g. Facebook, Twitter, LinkedIn or perhaps even to create photobook your image will be automatically downsized. Also, the software/upload process will randomly remove pixels without understanding what key elements are important in the picture.
The question is: ‘How often do you go through your photos?’ Do you really need to get more storage and take more photos which most likely you will not take the time to filter through? The other downside is that your file sizes will be signficantly larger which will in increase upload time online too!
How much do I really need?
This depends on what you are taking images for and how you will use them. This falls in to two main categories: 1. Print 2. Digital/Online
If you are going to print your images you will need to aim for higher resolutions. To work out how many pixels you will need for an image
4×6 = 2.2Mp
5×7= 3.2 Mp
Cover photos: 520 x 260 pixels = 0.14Mp
Sharing photos: 375 x 375 pixels= 0.14Mp
Cover photo: 851 x315 = 0.27Mp
Timeline photo: 960 x 720 = 0.69Mp
Large image: 2,048 x 2,048= 4.19Mp
Maximum 612 x612Mp = 0.37Mp
So as you can gather from the information above you don’t need a camera with 8Mp or more to print or share digital images. The key thing to focus on will be the size of your camera sensor.
Why does the sensor matter so much?
A ‘Full frame’ sensor (36x24mm) is the same size as a 35mm film negative. Currently you will only find this on pro-level DSLR cameras and with time it is likely this will change. In comparison a iPhone 6 has a camera sensor 1.5 inches (18.7x14mm).
What should I look for in a camera?
When you go to buy a new phone or a camera next time as the sales assistant how large the sensor on the camera is. Remember the larger the sensor the more light and therefore the higher the quality of your image will be. Furthermore, look for high ISO settings, this will allow you to take images in low light conditions and reduce any grain on it. Lastly, look at the quality of the lens. For a camera phone look for an aperture of f2.2 or lower if possible. What does this mean? It means that you will be able to take images with stability and quality in low light conditions. For anyone using a DSLR use prime lenses and aim for f1.4 or lower if possible.
So, the key thing to remember is; Where will I use these photos? This will help you to narrow down what camera to buy and ultimately save you in the long run!