Rohan is not able to contract his iris properly due to defect in his eyes. Rohan would not be able to see :
(i) in dim light (ii) in bright light
(iii) nearby objects (iv) distant objects

Explanation

(ii) In bright light. Since the iris is not able to contract, in bright light, too much light would enter into the eyes and Rohan would be not be able to see anything except a bright glare of light.