The simple answer is, make the horizontal version thinner. There’s probably a formula for this, but I just eyeball it. Typefaces are full of optical corrections like this, and a good lettering artist will make them almost unconciously when drawing letters manually.

I was hoping there was some rule that is used, but I guess not.

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I know I am in my own little world, but its ok. They know me here

I think it’s always going to be a bit subjective, depending on the sharpness of your own (bi-focal) vision and how near or far it is to be viewed from and so on and so forth.

That said, I’ve had (what looked to me like :) ) success with between 1% and 2% difference.

R

And a horizontal stroke at the bottom of a glyph will look heavier than the same dimensioned stroke at the to of a glyph. Forget the formulas and just draw the damn thing.

If it looks good it is good. (apologies to Duke Ellington)

I think type designers can sometimes exaggerate the amount of difference needed to counteract the optical illusion.
This is because we spend so much time looking at perpendicular strokes that are unequal, and imagining them as equal, that when we look at perpendicualr strokes that ARE equal, we imagine them as being unequal in the opposite manner to our habit.

It varies with the typeface: Here’s how much wider the vertical in the plus sign is than the horizontal,in a sample of typefaces: Gill 1.1%, Georgia 1.6 %, Californian FB 1.6%, ACaslon 6%, Franklin Gothic Book 8.6%, AGaramond Semi-Bold 19%.

As you can see there is no hard and fast rule. Because roman faces generally have heavy verticals and lighter horizontals, this also affects what looks ’right’, as well as the optical illusion. And then the style of the typeface also affects it. And different glyphs will be different. So as James says it’s your design and your eye in the end.

A way to get a feel for it is to look at other designs in a font editor, and compare them, as well as drawing your own.

You KNOW I chime in just to show off how willing I am to share the little I know. :)

R

R

Thanks for all the suggestions. I guess the best method is to examine other fonts in a font editor and then come up with a reasonable estimate as to what could be construed a “standard”.

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I know I am in my own little world, but its ok. They know me here

> I guess the best method is to examine other fonts in a font editor and then come up with a reasonable estimate as to what could be construed a “standard”.

Or you might just want to experiment, and use whichever option looks the best to you.

Thank goodness, there are no standards in typography.