Googlebot and generated image thumbnails

[harley77]

I'm noticing in the back-end log, I have a lot of 404 errors from GoogleBot not finding generated images (ex.

http://www.domain.com/system/html/imagename-9db61739.png

). This doesn't surprise me as I have cleared my image cache since the initial launch and the image would have been regenerated with a new name. My concern is, will this affect search ranking or any other search related activity in a negative way?

In robots.txt the system/html is specifically added so that bots can have access to it (as per Contao), but I wonder is it good to have unstable images (such as the ones in cache) being indexed?

[Ruud]

Why would Google look for an image that is not in the HTML of your page? Perhaps Google revisits images it saw on previous scans and removes them from their index when they do no longer exist? I can't image this affecting your ranking much...