Hi, I checked the Ink setup and handwriting recognition was already switched off so unfortuantely that is not the problem. With my system the Bamboo tablet is always on via a USB hub, and the mouse is only slightly better. I would probably need to talk with an Aperture apps person to understand if this is a driver issue or if it is an oversight in Aperture. We need to use the pen/tablet to avoid RSI in the hand from the mouse for such repetitive operations.
For single spots he response is sort of OK but for long lines it is slow. With film slide scans there are often black dust spots that need fixing. To be honest now I expect the slower response it is not so bad.
After about 4 separate spots Aperture seems to go away and re-make thumbnails so the 100% zoomed-in image goes fussy for about 5 seconds. It is as though some sort of auto save is on. Small cloning / retouch events seem to be treated as individual adjustments in the same way that say an exposure or levels adjustment is but you may need to clean up an image with 50 or more spots so you get interupted as it keeps doing an autosave and thumbnail correction even in full screen mode. Some rearrangement of the steps in the retouch proces may help.
For images from digital sensors the need to use retouch may not be so important as they should be clean, although sensor dust removal does seem to be an important topic for DSLR users and retuoch tool may be needed. For film users who make digital scans we definitely need a quick retouch system.
Also different zoom levels other than fit and 100% would be helpful for retouch as would a larger box for the pan of the zoomed in image. It makes it difficult to scan over the whole image looking for dust spots. With high quality lenses I do get image data at the pixel level (38M pixels from 35mm film) so I can't rely on general dust removal tools as they tend to remove genuine small spot like details such as distant birds flying etc.
Now I'm using the "exposure" adjustment more than "levels" as this seems to relate more closely to Photoshop levels adjustment that I'm used to.
Pushing the levels quarter tone slides in closer to the centre should do the same as a contrast enhancing S curve in Photoshop curves but I'm not tatally convinced, yet.