burnspammers,
In your previous post I see you've noted that you deselected "Sync Photos" and applied, which should erase the photos from the iPhone therefore no "yellow" space should be indicated in iTunes.
Since doing this did not erase the space dedicated for photos on your iPhone, it seems you may be experiencing a software issue on the iPhone itself (since it's not behaving as expected). In cases like this, I've found the best resolution is to restore the iPhone, setting it up as new and re-syncing the photos back.
Backing Up, updating, and restoring your iPhone and iPod touch software
http://support.apple.com/kb/HT1414
I personally just deleted the iPod Photo Cache, synced over a groups of photos 10.3MB in size (as shown on my computer), which re-created the iPod Photo Cache folder at 4KB and took up 6.5MB on my iPhone. This particular group of photos were originally taken with my iPhone, so I did the test again only this time syncing over a larger amount of photos originally taken with my Canon camera. This group of photos shows up as 138.7MB in size on my computer, created the same amount of iPod Photo Cache as before (4KB), and only took up 52.9 MB of space on my iPhone.
I did test syncing a few more times in an attempt to "bloat" the size of iPod Photo Cache and the amount of space taken on the iPhone, however the sizes didn't really change, even though iTunes displayed it was optimizing the photos, then synced them.
Hope this helps,
Raleigh