Stopping down increases depth of field but, past a point, diffraction blurs the whole image. The calculator compares the Airy disk (the blur spot from diffraction) with your sensor's pixel pitch and shows the diffraction-limited aperture (DLA).
Enter pixel pitch directly, or look it up on your camera's page in our camera database.
How it works
Airy disk ≈ 2.44 × λ × N (λ = 0.55 µm). DLA when the Airy disk ≈ 2 pixels: N = 2p ÷ (2.44 λ).
FAQ
Should I never shoot past the DLA?
No — DLA is where softening becomes measurable at 100% view. For prints and web, f/11–f/16 on full frame is often fine when you need depth of field.
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