There's no photographer listed as that address in Thom's 1938 ..
48 O'Connell Street Lwr
Premier Tailors (Ireland) Ltd
Freely Bros & Co., Jewellers
Charles Barklie, estate agent
In 1943 the only difference is that the ground floor is occupied by Joseph Cafolla, ice cream parlour
In 1927 the Freely jewellery business is listed at the address, along with Frewen & Ryan, hosiers, glovers & outfitters and also listed is the London Gen. Assurance Co.
Most of the Dublin city photo studios seem to be listed in the directories but I suppose it's possible that some smaller studios were not... or this particular studio didnt operate for very long at this address
Is the address clear ?
In 1938 the photographers listed on the street are :
14 - H. Cowan
55 - H. Roe McMahon
Shane