I have Preview version 8.0 (859.21) and OSX daily suggest it should be able to convert to GIF. http://osxdaily.com/2012/08/29/save-images-as-gif-other-formats-preview-mac-os-x/ My version of the only has 6 items. See enclosed. I have reinstalled Yosemite --- Post Merged, May 30, 2016 --- I got it. You must hold down the "Option key" to see all options. This is strange why not show all options without the key.