@@ophthalmologypearls thank you for your response, got it. I have another question. When we do ret on model eye with dummy lens. Let’s say I got reversal in 90 meridian which mean I got reversal at vertical and aganist in horizontal 180 meridian. My ques is that when adding negative cyl in which position do I need to put axis of cyl?
Let me get this straight. I think you mean - After reversal and subtracting for distance and cycloplegic drug, you get a plus power in the vertical meridian & a minus power in the horizontal meridian. So if you want to put a negative cylinder (minus cylinder), we want that minus power in the horizontal meridian. We know that cylindrical lenses have their power perpendicular to their axis. So a negative cylinder has to be placed with its axis at 90°, for the effective minus power to be available horizontally
