Yam Shel Shlomo(Kesubos 2:3): R’ Yosse [Kesubos 17a] asserts, “It is permitted to stare intently at the face of the bride for the first 7 days in order that she become beloved to her husband” - but that is not the halacha. And even the first day of marriage it is prohibited so he should instead stare at her clothing or jewelry but not at her face at all. In contrast all of this is absolutely prohibited for other married women. It seems that this is only in reference to staring in a manner that it is prohibited to stare at a rainbow which is in a manner of examination and staring – but simply in a manner of glancing it is permitted. Glancing is also permitted in regard to all married women. Even though from the Rosh (2.3) it appears that even glancing at her face is prohibited but that doesn’t make sense because then no one would be able to know whether a particular woman was single or married that they could testify concerning her. It is specifically talmidei chachomim that Bava Basra 168a say normally do not pay attention to a woman’s appearance. This implies that glancing is permitted even for a talmid chachom, while the average person generally pays attention even to recognize a woman. And the gemora there concludes that when a talmid chachom pays attention to the appearance of a woman he is fully aware of what she looks like. Thus this indicates that looking at a woman is not prohibited but it is only the minhag not to. Therefore we can conclude that there is no actual prohibition at looking at women but there is for staring and carefully examining her image. Staring would also be prohibited even to examining her clothing as we see in Avoda Zara (20b). This is also the view of the Ramban, It is prohibited to stare at the beauty of a woman – even at her little finger with the intent to derive pleasure... This seems to be in agreement with what I explained. Nevertheless one who can be cautious and to add restrictions and safeguards and he is pious and it is known that he is not doing it for pride and to show off – he is called a holy man and he is blessed.