We've all been there. You buy a shiny new digital camera, take a picture of your dog/car/sunset/mate falling over and can't wait to share it with the world. So you email them the whole file. Their email locks up for about 3 days trying to receive a 10 mega pixel file and even worse, when you upload it to the ThinkCamera gallery you get told that the file size is too big.
Well, stay tuned. This article will tell you how to resize your picture to a more acceptable size. You'll need a computer and some software but we'll take you through the steps on four of the most popular packages - including free software for both the PC and Mac.
Image size vs. file size
There are two things to think of when resizing a picture. One is image size and the other is file size. They are related but separate.
First of all image size is simply the number of pixels in the picture. Shoot at 3000 X 2000 and that's a 6 million pixel image. You can use compression to reduce the file size but if you don't reduce the image size first then the quality is going to be terrible. A good rule of thumb is to make the picture between 600 and 800 pixels on the long side. This gives nice quality on most people's computer screens without being too big to send. If you know that your recipient has a monitor with a higher resolution then you could send it at something like 1024 pixels but usually 800 pixels is just as good.
File size should be the final consideration once you have resized the image. There are lots and lots of formats to pick from but the best is generally jpeg (or “jpg”). This gives relatively small file sizes and is optimised for photographs (as opposed to something like gifs which are great for line drawings). Other formats do this too but the advantage with jpegs is that just about every computer can read them. They are understood by all operating systems produced in the last 10 years or more and all graphics packages. If you want somebody to be able to open your picture at the other end then jpeg is a great choice.
Jpeg is a lossy format - the smaller you make the file the worse the quality gets. Fortunately we can see exactly what we are doing as we save it - if it looks bad to you then use a higher quality setting.
Ratios
Before you start take a look at your picture. Chances are it's rectangular. We want it to stay that way. If you just resize one dimension then people are going to look ridiculously tall - or even worse, fat. We don't want that so make sure that you resize each dimension by the same amount - it's as simple as selecting “preserve aspect ratio” or something similar when you resize.
The software
As I mentioned at the start, we're going to look at 4 different packages. Which one you use is entirely up to you and simply depends on what you already have. (Click the program name to see the related tutorial)
- Photoshop / Photoshop Elements - these are the market leaders of photo editing applications. This tutorial walks you through the steps on Photoshop Elements but Photoshop works exactly the same way for this.
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Irfanview - by far the best free jpeg viewer on the PC. Not only is it very quick it has a ton of features including photo resizing and batch functions. Oh and it's free. You can get a copy here.
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Graphic Converter - included here because it used to be bundled with Macs. It's one of the best featured graphic conversion applications you can get. It's shareware - try before you buy. Get a trial here - it costs $30 if you're hooked.
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iPhoto - not free software but it comes with all Macs. It needs you to import the pictures into iPhoto before you can work on them (though that's no bad thing) but after that it's just “stupid easy”.
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