Controlling images in album set thumbnails

I’m using the Galleria add-on and have a question about album set thumbnail pages. Right now, every time you select the album set by clicking on the top of a drop down menu of albums, a different image from the gallery appears in the thumbnail. I would like to make the image that appears in these thumbnails always be the first image in the album. Is there a way to do this?

My website is https://www.bobcornelis.com/BacklightTest

Click on Printmaking or Photography to see the thumbnails I’m referring to.

Thanks!

You can do this in Backlight Publisher. Navigate to the album, click on the picture you want to use as the cover image.
A large version of the image will appear. Click on the image icon in the upper right. You can then assign the image to be the cover image.

Thank you Rod! That worked like a charm.