In retinoscopy for refractive error at 1 m we add 1D if done at distance of 66 cm, the addition factor will be:

B i.e. -1.5 A rough estimate of refraction is made by taking into account the retinoscopic findings, deductions for distance (e.g. 1D for 1 metre and 1.5 D when retinoscopy is performed at 2/3rd meter distance) Q and deduction for cycloplegic when used (e.g. 1D for atropine, 0.5 D for homatropine and 0.75 D for cyclopentolate) Q.