If you've lost access to the original and need it, just reach out to us at email@example.com or use the chat window at left. We'll be happy to get it for you. The easiest way to be specific about the image is to send us a link for the image.
Unfortunately, we currently cannot replace or update an image used for a picture that already has content in it. Probably the easiest thing to do is to add the replacement picture and copy over the content. Let us know if you need help with this. Audio recordings, for example, can be tricky. Once you're done, you can delete the original flawed picture.
By way of background, a picture as viewed in Ponga isn't a .jpg, .png, or .tif image file. It's a web page. When you upload your pictures to Ponga, we process them for inclusion in Ponga, then preserve your original image files in our archives. That means that the entire file with all metadata and image file names are preserved, unchanged. When you "right-click" or otherwise attempt to download a picture from the Ponga browser window, the file isn't there. It's a web page.
We do this because it allows us to deliver very high resolution images across low-bandwidth networks by tiling the image into little squares. This is a lot like the way you use Google maps to zoom around any part of the world. You're not looking at a giant map, but only the part of the map you need to see at a time. You'll have noticed little tiles refreshing when you zoom quickly in or out of a very large image. Your viewers can take screenshots, but they don't get the original image. Only the owner can request the original file.
Reach out if you have any questions.