As seen in pond, first visit.
Mulwray in glasses as seen by Gittes through binoculars
Glasses fished out of pond, shown to Evelyn Mulwray at the house Kathryn is staying at.
This is not well-played by Polanski. The glasses could not be mistaken the one for the other. Yet, Gittes confronted Evelyn with them, accusing her of murdering Hollis in the pond, knocking his glasses off. Evelyn has just told Gittes that those are not Hollis', as can be seen at a glance they are not, but not because Hollis' glasses were tortoise shell and these (Noah Cross') are wire rims, because these are bifocals and Hollis didn't wear bifocals. I don't buy that. Evelyn distinguished the glasses while hardly looking at them. She would know at a glance that they were not Hollis' because not tortoise shell. To distinguish them while hardly looking at them because the wire rims are bifocals is not credible. Gittes has to examine them closely to tell. You can see the bifocal magnification of the eyeglasses' arm in the lower half of the right lens. No, I don't buy it. Evelyn was still protecting Noah. She said that they were not Hollis' but did not say they were Noah's. Why was she protecting Noah at this time? She has just told Gittes that Noah raped her and that Kathryn was "my sister, my daughter." Not well-done.
At Evelyn's house, Evelyn is not home, she is with Kathryn; Gittes lays the glasses down on a table while he calls Cross and tells him to come to Evelyn's house. He is going to confront Cross with the glasses, which he has now figured out are Cross', and that he is the murderer.