> For the complete documentation index, see [llms.txt](https://docs.kostacloud.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.kostacloud.com/optimization/imaging-optimization/third-order-metrics.md).

# Third Order Metrics

### Assumptions

For all 3rd order calculations in KostaCLOUD, We assume:

* The system can be represented as an unfolded system.
* The calculated sequence information is factual.
* We currently do not account for bifurcation of sagittal and tangential planes

For systems that break these assumptions, please use real-ray tracing routines. We have only a few of these operands which are approximated via real ray tracing.

### Spherical Aberration (3rd order)

**Details Coming soon**

### Distortion (3rd order)

**Details Coming soon** 

### Astigmatism (3rd order)

**Details Coming soon**

### Field Curvature (3rd order)

**Details Coming soon**

### Chromatic Defocus (3rd order)

**Details Coming soon**

### Lateral Color (3rd order)

**Details Coming soon**

### Pupil Spherical Aberration (3rd order)

**Details Coming soon**

### Pupil Distortion (3rd order)

**Details Coming soon** 

### Pupil Astigmatism (3rd order)

**Details Coming soon**

### Pupil Field Curvature (3rd order)

**Details Coming soon**


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