2. Launch the program, you should arrive on the login page. Click on the wrench icon (highlighted here in red) to add the cai-omero server.
3. Click on the button of the next menu and enter the server address: omero-cai.hhu.de
4. Select the server from the list and confirm the changes with
5. Enter your username and password
In case of field images from the Operetta, do NOT select the individual images for upload but the "index.idx.xml" file in the "Images" folder. OMERO will automatically extract the image information from this file and upload all images into a plate-well-field hierarchy and visualize it in a plate frame.
If you want to upload continuous images recorded at the Operetta, such as tissues on slides, then you first have to stitch the images before uploading (e.g. by using the Fiji plugin "Operetta importer").