Thalasar Ventures

One of the interesting thing about software design is how the intial assumptions tend to dominate the initial design. A lot of captchas had the initial design of reading letters or numbers that have been distorted or bent out of shape.

Blogger.com currently uses the highly bent letters approach and other software packages overlay bands of color on top of the numbers or letters. Captchas’ were originally designed to the stop automated submission of comments and various forms of site defacing. The problem was the initial captchas were visual – read this distorted image or read that distorted image. This promptly started an arms race of sorts – Russian programmers spent time developing better image recognition software and captchas designers making ever more distorted versions of the images and letters. This is a bad initial assumption and quite simply isn’t supportable in the long term. Image recognition is something that lends itself to algorithmic development. Yet the real goal of the captcha is to make sure a human being as opposed to a piece of software, but many captcha designers have taken an automated approach for dealing with the problem. Instead of an increasing convoluted image why not ask the person question? For example who was the 24th president of the United States? What’s 4 divided by 2 plus 3? What was the Titanic’s sister ship? You could chose a different answerable question of the day, something easily researched by wandering over to Wikipedia. You could make the question about something your own site – “What’s the headline on the About page?” and then users could wander over to your about page and copy and paste it.
If you are going the distorted image route, please let people know the rules of your captcha. For example it’s far too common not to let people know whether or not the letters need to be capitalized. Having your users guess is a painful experience.
You can also have multiple questions to confirm the person’s “humaness”. While this might hinder site conversions it would also stop the escalation of nearly impossible to read images. Right now many captchas are so distorted it takes multiple tries to get one that is legible which is also pretty annoying. But with a little creativity you can design a quality captchas that your users might enjoy. At the very least you can improve their experience at your site by getting rid of those impossible to read images!