OK, the only way to deal with the variability of where you get to shoot from, vs. where downfield the action is occuring, is to provide you with a table of FL and distance, showing Field of View for FF sensor...and you can derive longer Fl as proportionately smaller FOV, and shorter FL as proportionaly larger area captured. For example, 250mm FL has 2X the FOV as 500mm
(and you can derive APS-C FOV as 60% of the FF dimensions captured)
300mm
50' dist: 4' x 6'
100' dist: 8' x 12'
200' dist: 16' x 24'
300' dist: 24' x 36'
400mm
50' dist: 2.9' x 4.4'
100' dist: 6' x 9'
200' dist: 12' x 18'
300' dist:18' x 27'
500mm
50' dist: 2.3' x 3.5'
100' dist: 4.7' x 7.1'
200' dist: 9.5' x 14.3'
300' dist: 14.3 x 21.5'
It allows you to detemine what FL is 'too short' and what FL is 'too long' in what situations, in consideration of different zoom FL ranges.
And if you keep in mind that 100' across the field AND 100' downfield = 1.414 * 100', or 141', you get an idea of where downfield the action is.







