Ophthalmology In retinoscopy for refractive error at 1 m we add 1D if done at distance of 66 cm, the addition factor will be: A -2 B -1.5 C -0.5 D -5 💡 Explanation In retinoscopy for refractive error at 1 m we add 1D if done at distance of 66 cm, the addition factor will be: ✓ Correct Answer: B. -1.5