Most time telling devices we use devote display area roughly equally for each digit. Minutes, hours and seconds on a digital clock are all given equal weighting visually. The same roughly to analog clocks. Something like a sundial or, to be more direct, the act of looking at the suns position in the sky goes not do this. But these both make it hard to judge small changes in time.
There are only 86400 seconds in a day. Thats not a big number if you're used to dealing pixels. Here is a simple clock that shows time in a unary fashion. Each pixel ticked off is one second of your day gone.