Yep, a straight sided cup would work fine also. You could even use a
ruler to measure the amount of rain in the cup if you needed a real
accurate measurement. I was aware of using a cup like you mention and
even thought about it. The fact is, it's not only my legs that are
bad, my eyes aren't much better either. I call it old age.......LOL
The rain gauge I bought is large at 13" high and it also magnifies when
it has water in it with nice big numbers. Hopefully this should serve
me well in the garden.

Rich