Modified 3-Standard Fields
| Calibration Field (CF): | The whole of the optic disc and macula must be visible in the field. |
| Field 1M - Optic Disc: | Centre the temporal edge of the optic disc at the intersection of the cross hairs. The optic disc will be off centre providing a partial view of the macula. |
| Field 2 - Macula: | Centre the macula at the intersection of the cross hairs in the ocular. A suitable position can often be obtained by rotating the camera temporally from the Field 1 position. Please note that centre macula is below the centre of the optic disc. Lower the field as necessary. |
| Field 3M - Temporal to Macula: | Position the intersection of the cross hairs in the ocular 1.0-1.5DD temporal to the centre of the macula. In this position, the macula will appear mid-way between the edge and the centre of the monitor view. |
Tip: It may be easier to achieve the correct F3M field definition by using the internal fixator and then removing it just prior to taking the photograph.
