We have sailed twice on Braemar. For informal evenings, for ladies, a long dress, short cocktail dress or trousers and a 'glitzy' top, perhaps with some jewellery is quite acceptable. For semi-formal it's much the same but maybe with less glitz. For men, a DJ or dark suit is acceptable.
Go to www.fredolsencruises.com and select A-Z of Cruising. Select letter "D" and scroll down to Dress Code, this will tell you all you need to know.