Hi, my tomato plants (and now possibly my peppers) have white spots on the leaves. The new growth doesn't seem to have it yet, but it's only been a week or so that I've been monitoring this prob. From what I can see in my searches, most fungi, etc. seem to have brown or black areas inside the white spots.

These seem to just be white/dead spots on the leaves. One search I came upon said this might be zinc or magnesium deficiency and suggest adding compost. Did that 5 days ago.

Thoughts? Second opinions?