| Power of Diopter | Focusing Distance on Lens (in Feet) |
Actual Distance Focused on from Diopter (in Inches) |
| + ½ | Infinity | 78 3/4″ |
| 25' | 69 1/2″ | |
| 15' | 64 3/4″ | |
| 10' | 59 1/4″ | |
| 6' | 51″ | |
| 4' | 43 1/4″ | |
| + 1 | Infinity | 39 3/8″ |
| 25' | 34 3/4″ | |
| 15' | 32 3/8″ | |
| 10' | 29 5/8″ | |
| 6' | 25 1/2″ | |
| 4' | 21 5/8″ | |
| +2 | Infinity | 19 5/8″ |
| 25' | 18 1/2″ | |
| 15' | 17 3/4″ | |
| 10' | 16 7/8″ | |
| 6' | 15 1/2″ | |
| 4' | 14″ | |
| +3 (+2 and +1) |
Infinity | 13 1/8″ |
| 25' | 12 1/2″ | |
| 15' | 12 1/4″ | |
| 10' | 11 7/8″ | |
| 6' | 11 1/8″ | |
| 4' | 10 3/8″ | |
| +4 | Infinity | 9 7/8″ |
| +5 | Infinity | 7 7/8″ |
| +6 | Infinity | 6 1/2″ |
| +8 | Infinity | 5 |
| +10 | Infinity | 4 |
| NOTE: Film Tests Should be Used to Verify Results | ||