I am having the same problem for the first time, since upgrading my iphone to iOS 8, even though I have never had it before in the several years I have been using the app. I am downloading using the Photo Transfer App on both iPhone and MacBook, and there is no obvious place to select to download full size, but it has always worked fine in the past. One odd thing: when I download ONE photo, it is full size. When I download a collection of photos including that same one, they come in much smaller size, although a couple here and there were full size. I also tried using the online app, which does allow you to select full size, and they also came in reduced size. I'm going to experiment and see how many I can download at a time and maintain the full size, but it is very tedious, as I have hundreds of photos from a 2-week vacation that need to be downloaded.