I just converted a PDF with many image pages (because I needed to convert to PDF to crop all pages at the same time) to PNG... and I got one large PNG file that apparently had all my images in it... Opening it in Preview would show all the images in their thumbnails just like with GIF and PDF files. But opening it in Safari would show the images one by one as it loaded... ?? I had no idea it was possible to have multiple images in one PNG file. How does it work? And how do I split the combined images into separate files so I can actually upload them??