Image dims when viewing in full screen in iphoto on thunderbolt monitor I'm using a Macbook Air along with a Thunderbolt Display. I am experiencing a problem in iPhoto wherein images are dimmed ONLY on the Thunderbolt display and ONLY in full view mode.

When using iPhoto, and when viewing in thumbnail mode, all of the thumbnails appear as they should w/rt color and brightness. But when I doubleclick on an image to bring it up in full view, the image is significantly dimmed -- As if a 20% transparent black layer were overlaid on top of it.

When I view the same images in slideshow mode on the thunderbolt, they appear just fine!

And when I view the same images in full view mode on the MB Air monitor, they also appear just fine.

The problem appears to be w/in iPhoto, as there is no systems calibration setting that I am aware of. 

Does anyone have a suggestion about how to fix this so that the images appear unaffected on thunderbolt in full view mode?
I am seeing the same thing here with a MBA on the TB display. All fine on MBA display, and thumbnails on TB, but once you zoom up the photos on the TB display they become 'darker'. 

If I export the photos out of iPhoto and display them in Preview/quicklook, they don't go darker. It is only iPhoto that is rendering the images with some colour profile. 

I couldn't find an answer but a restart of the computer fixed the issue. 

Using iPhoto 9.5.1 running OS 10.9.4 on MacBookAir5,2.