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Äquidensite f
phys.	curve of equal optical density (of the first, second, n-th order); equal-density curve (of the first, second, n-th order); equal-optical-density curve (of the first, second, n-th order); equal-density line (of the first, second, n-th order); equal-optical-density line (of the first, second, n-th order); equidensity line
Äquidensiten f
opt.	lines of equal density