11-05-2015, 09:16 AM
(This post was last modified: 11-05-2015, 09:17 AM by Brightcolours.)
Not taking any field curvature into account, indeed focussing at the horizon/infinity/main subject gives the best results.
http://www.trenholm.org/hmmerk/DOFR.html
http://www.trenholm.org/hmmerk/DOFR.html