The retinoscopy calculator automatically calculates the final refraction based on the entered retinoscopy values, while also accounting for the correction based on examination distance.

​

In addition, it allows adjustment of the result according to the cycloplegic agent used. The stronger the cycloplegic, the more of the spherical value is subtracted (Tonus Allowance). This is because in the natural conditions a certain minimal accommodation is still present. If this is not considered, the resulting correction might be less tolerable for the patient or it could lead to reduced visual acuity.