The /dcm4chee-arc/ui2/ admin page shows the J4Care logo by default on the bottom left corner.
You can find some instructions on changing the logo here
UI Appearance Customization · dcm4che/dcm4chee-arc-light Wiki · GitHub
Changing the Background Image and Logo
The UI would expect the new Background-Image or/and Logo-Image to be in <ui-host>/resources/img/ with the names:
bg.jpgfor the new background (<ui-host>/resources/img/bg.jpg)logo.pngfor the new logo (<ui-host>/resources/img/logo.png).
If there aren’t any images in this location, UI will consider the default background and logo images for background of archive UI and logo displayed at bottom right respectively. If you are using the dockerized version of the Archive and UI, you have the possibility to paste those images in a sub-folder ( ui/configuration/resources/img ) of the mounted folder of the archive UI (default defined as var/local/dcm4chee-arc) respectively in /var/local/dcm4chee-arc/ui/configuration/resources/img.