Yannick - hi! This is not product-related - it's a general question about SEO.
I asked the guy who administers my web site about a tool to help with reorganizing the images on my site (they are scattered in NUMEROUS directories, MANY images are duplicates, and MANY images are no longer in use because of changing look-and-feel of our site) and he suggested two. (FYI - I looked at both and decided to go with R2H ImageManager.)
His reply to my question also included this caveat:
Removing / Changing url / compress with new suffix may also have a bad impact on Google indexed pages, so this is a long and delicate work to be done in which many aspects must be taken into consideration and which will be evaluated for each single page or article.
To me, changing the URL and/or compression for an image file seems it would have a small (if any) impact on Google index and search results.
Is possible impact as big as he makes it seem, or is impact relatively small?
BTW - Perhaps 4SEO could provide a list of "Do's and Don'ts" for changes to web pages - not as interactive checklist, just as static reference. As an SEO amateur, I'd find that a useful feature.
Thanks for letting me pick your brain!
Best, Todd