I am often asked, with the huge improvements in the cameras fitted to smartphones, why anyone should buy a conventional camera?
Let’s start by talking about tiny dots
Most of the photographic work that I do these days is transferred to my clients on a USB drive or via an online gallery where they can download my photographs and add them to their own libraries.
Frequently, when I ask the client if they want the images only as 300 dpi or as both 72 dpi and 300 dpi, I’m met with silence. It seems that a lot of people don’t really understand what Dots per Inch, or DPI means, and are afraid to admit it.
Nobody should be afraid to ask for help. Having started doing my own printing 44 years ago, I’ve grown up with the transition from film to digital and I’m happy to advise anyone who finds a lot of camera and software “speak” a foreign language.
So for anyone who wants to gain a better understanding, this is a simple guide.
All digital images, whether they are photographs or graphics, are made up of thousands of tiny dots.
Smartphones, by default, record at 72 dpi and cameras normally record at 300 dpi.
It doesn’t sound like such a huge difference – but it is. 72 dpi means 72 dots per inch horizontally by 72 dots per inch vertically. So 72 dpi x 72 dpi gives you a total of 5,184 dots of information in a square inch.
300 dpi means 300 dots per inch horizontally by 300 dots per inch vertically. So 300 dpi x 300 dpi gives you a total of 90,000 dots of information in a square inch.
That’s more than 17 times as much information as in a square inch of a 72 dpi image.
So, why not plan on photographing everything at 300 dpi?
There are two reasons. One is the size of files that are generated at 300 dpi and the other is that, if an image is only going to be viewed on a computer screen, smartphone or tablet, you don’t need 300 dpi files.
Some web designers reckon that 100 dpi to 125 dpi is good for the latest “Retina” screens on mobile devices, but the files are still a fraction of the size of a 300 dpi image.
Take a look at the two photographs below. One has a resolution of 72 dpi and the other is 300 dpi. Can you tell which one is which?
It’s unlikely you can because the screen on your computer, tablet or smartphone simply cannot make use of the extra information that is contained in a 300 dpi file.
The 300 dpi image at 7” x 5” has a file size on disk of 3.31 Mb. The 72 dpi image at 7” x 5” has a file size on disk of just 312 Kb, which is less than a tenth of the 300 dpi version.
300 dpi files are for printing. 300 dpi is also the limit for what the human eye can see in a print.
Of late, we have all got used to storage getting cheaper and cheaper. We’ve got used to free Wi-Fi and super fast broadband wherever we go. So we’ve all got a bit casual about file sizes.
We’ve forgotten about the days when portable storage was on 1.44 Mb floppy discs (which would hold just four of the above 72 dpi photos.) We’ve forgotten about dismal dial up modems that transferred data at glacial speeds and e-mail systems that would fall over if you tried to send anything other than the tiniest file attachment.
So why worry about file sizes in the modern era of computers and smart devices?
It used to be believed that, if a website landing page didn’t load within 10 seconds, the viewer would go elsewhere. With tablets and smartphones, people now expect pages to load instantly. If you have lots of un-optimised images on your website, that slow down pages from loading, you are going to lose your viewers.
Look around in any public place these days and you will see people frenetically scrolling down the screen of their tablets and smartphones. Everyone is in such a hurry to see what one of their thousand closest friends has got to say for themselves today!
Your own website analytics will tell you what percentage of your visitors are using mobile devices and you can be certain it will only be going up each year.
Smartphone or Camera?
If you are only need 72 dpi images, why not just use a smartphone all the time?
The built in cameras you find in the latest smartphones are so much better than they were even just a few years ago. With a little bit of care and a minute spent processing the image, you can get results that are more than acceptable for blog posts and social media.
But the images will still not be as good as those that have been shot on even a relatively cheap camera at 300 dpi and then dropped down to 72 dpi on a computer.
People think that, the more megapixels a smartphone camera has, the better the final result will be. It certainly helps but the quality of lens that you are shooting through is even more important and smartphones are still playing catch up.
I use an Apple iPhone 6 Plus. The current equivalent model is the 8 Plus, which costs £799.
In the photograph at the beginning of this article is what I call my “holiday camera”. It’s a Sony RX10 Mk II that can currently be bought for £810. It produces the most incredible images that are more than capable of being printed to over A3 size, thanks to its Zeiss lens and having one of the best camera sensors made. It is beautifully built and will last for very many years.
Cameras costing a fraction of what the Sony costs will still produce better photographs than a smartphone (for now at least) as that is what they have been designed to do.
If you are part of that generation who have never used conventional cameras before, find a friend with a conventional camera and borrow it for a weekend. It will open your eyes to another world.