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Optics & resolution

How I compare optics

Comparing optics by magnification alone is one of the most common early-career mistakes.

One of the biggest mistakes I made early in my career was comparing optics by magnification alone.

How depth of field shrinks at high magnification
Depth of field is one of the criteria that magnification alone tells you nothing about.

What actually matters

  • Resolution
  • Working distance
  • Depth of field
  • Illumination compatibility
  • Throughput
  • Mechanical constraints

My evaluation process

  1. Determine the smallest feature that must be resolved.
  2. Determine the required field of view.
  3. Determine the cycle time.
  4. Test multiple optics against real parts.
  5. Validate with production-representative samples, not just the nice ones.

The lesson

The best optic is not the most expensive optic. It is the optic that solves the problem while satisfying all the constraints.