- Other achievements of Aepinus include improvements to the microscope, and his demonstration of the effects of parallax in the transit of a planet across the Sun's disk.
- An improved configuration uses a splitter mirror to eliminate the effects of parallax but not the differences in lenses.
- Each element was then centered in the lens to decrease distortion from lens curvature or parallax.
- The actual contact times for any given observer may differ by up to 7 minutes due to the effects of parallax.
- It is easier to see the effect of parallax the closer the foreground object is to you.