Hello dear...1. There may be difference of 0.5D astigmatism on undilated and dilated refraction...this is normal ....like if u check ur weight it may b say 60kg aand after 10 min. If u recheck weight it may be 60.2kg...so this is normal variation.... 2. There is discrepancy between astigmatism on topography and cylinderical number that u wear in majority of people...because topography tells shape of cornea ...patient may or may not accept same cylinder as on topography

Rely on undilated eyes value as it is one you are going to live. Forget rest those are for academic discussion only.