With Poser 12, you even have an easier way: just drag an image file from your file explorer directly in Poser's Material Room, in a place where there's nothing.

And if you do the same on an existing image node, Poser will ask what to do, letting you the opportunity to search and replace all occurences of the same picture with the new, be it on the figure, the scene. The choice is up to you ?

Example:

𝒫𝒽𝓎𝓁

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(っ◔◡◔)っ

👿 Win11 on i9-13900K@5GHz, 64GB, RoG Strix B760F Gaming, Asus Tuf Gaming RTX 4070 OC Edition, 1+2 TB SSD's, 6+4TB HD
👿 Mac Mini M2, Tahoe 26.4.1.2.3.4.5.6.7...., 16GB, 500GB SSD
👿 Nas 10TB
👿 Poser 13 and 14 ❤️

𝑀𝓎 𝒢𝒶𝓁𝓁𝑒𝓇𝓎