Running WordPress V. 7.3.17, theme Twenty Sixteen Child Theme, Responsive Lightbox & Galleries 2.2.3.1
Recently changed some images in an existing gallery (1 of 19). From the back end the images look tiny compared to existing images. On front end, 7 of the 19 galleries show mostly the portrait oriented photos as much bigger than the landscape oriented images. Downsizing enough to make them show similarly results in very low quality image (less then 200 pixels on long side). It is unknown when this problem began but sometime in the last couple months. I have tried deleting all the images in a specific gallery, then re-adding them as well as completely deleting the gallery page and creating a new one. No effect on problem. Until this problem was discovered, I have sized the photos usually 800 on long side for landscape & 600 on long side for portrait and they all looked basically the same size on screen. Any assistance appreciated.
