Simple Instructions:
Create an Adjustment layer then apply 2 effects, the Bulge and Magnify effect.
Bulge Effect:
- Horizontal Radius
- Vertical Radius
Magnify:
- Magnification
- Size
Adjustment Layer:
- Set Expressions to Bulge and Magnify Center then connect to Position (Adjustment layer position)
Null Object - Main Control for the Magnifying Glass:
- Add expression to the Adjustment Layer Position and connect it to the position of the null object.