OSLO evaluation graphs of 8" Stevick-Paul telescope

The following OSLO EDU v6.2.2 (see Sinclair Optics) Evaluation graphs were produced from this Stevick-Paul8.len file. The OSLO Surface parameters were calculated from David Stevick's equations (see his Stevick-Paul telescope design pages) using my
Stevick-Paul.xls Excel spreadsheet (.zip w/ .xls and .len). The Strehl ratio for this configuration is reported as .999733

Equations used with permission from David Stevick.

OSLO evaluation graphs
Optical System Layout
Ray Trace Analysis
Spot Diagram Analysis
Wavefront Analysis
Point Spread Functions
Modulation Transfer Function through-Frequency
Modulation Transfer Function through Focus

The following are single spots at focus for the Center and 4 edge of field points designated North, South, East, and West to show performance all around the field. The Center and North are the same points plotted in the Spot Diagram Analysis
Single Spot - In Focus: Center
Single Spot - In Focus: North
Single Spot - In Focus: South
Single Spot - In Focus: East
Single Spot - In Focus: West

Last is an 8" Parabola Spot Diagram Analysis for comparison. This graph is scaled the same as the Stevick-Paul Spot Diagram. Compare the top center spot of each (representing in-focus image at the edge of field). The Parabola Spot shows the coma characteristic of a parabolic mirror. Note the significantly reduced spot size in the corresponding Stevick-Paul Spot.