Re-sizing images during conversion

On books that have lots images, in the past I'd sometimes tick the 'Resize images for palm devices' check box when I do a conversion to MOBI and end up with a file that is much smaller in size and still has decent looking images (at least as viewed on my K3).

I've found that this option is present in 0.8.14 that I've been using, but on my version of calibre portable 0.8.47 I don't see that option (under "MOBI Output"). Is it gone? Has that option been disabled, or moved? I didn't see it under 'tweaks'....

If it's gone - is there some other way to force the resizing of images when doing a conversion? Am I missing something?

Thanks!