big vs. small casio digital watch legibility comparison

I own a bunch of Casio digital watches. Something I've always found amazing is the size of a Casio digital watch does not dictate how legible it is... at least most of the time.

What works for something good and legible for a digital depends on a few factors.

Digital segment crispness, thickness and spacing

The digital segments have to be crisp but not too crisp nor too soft. Decent thickness and spacing of segments need to also be there so you can read the time easily.

LCD panel color

The panel has to be light gray. All other colors take away legibility.

Design flaws?

This is identifying anything in the design of the watch which takes away from legibility.

Comparing 4 Casio digital watches I own

At left, Casio W218H. At top, Casio MWD100H. At right, Casio WS1600H. At bottom, Casio F-91W.

All of these look like they have the same legibility. They don't.

The most legible is the W218H by a country mile, followed by WS1600H, F-91W and then MWD100H.

Yes, this means the biggest of the 4 has the worst legibility. Why? It has a slightly yellowed LCD panel, and the case insert middle bar (where it says "FIVE ALARMS" in the middle of the display) casts a shadow. None of the others have that.

That middle bar is a design flaw. In bright daylight viewing, the cast shadow of that bar is so bad that I have to rotate myself away from the sun just to read the time.

The W218H is best because its digits are large, spaced wide, and the panel is completely uncluttered. That's as good as it gets.

The WS1600H is very close to the W218H in legibility, but the digits are slightly thinner.

With the F-91W, it has top tier daylight legibility, but it's night legibility where it fails miserably. The night light on the F-91W is garbage, whereas the light on the W218H is amazingly good and isn't restricted to a 1.5 or 3 second afterglow. You can hold down the light button for as long as you want and it will keep shining.

Big size for legibility only matters when the bigness is in the right place

Here's an example of three big digital watches from Casio: Casio AE1500WH, Casio WS1500H and Casio WS1700H.

The WS1700H and WS1500H in reality are only about as legible as the WS1600H seen above. You don't get more legibility with the larger case size. You get other features such as tide graph, moon phase and fishing timer, but no real appreciable legibility advantage.

Only the AE1500 has its bigness in the right place. The time display is huge, and date display is also fairly big. When you want a genuinely large time and date display from a big watch, AE1500 is the only way to go.

Published 2024 Sep 24