MLUSTECK  I fear the communication with iPhoto is not yet possible, and as I use the platform-independent Qt-library it will probably not be for some time. But something I will implement in the next release is simple drag&drop, you drag a file or image onto the enlarger-window to open it. And of course iPhoto supports drag&drop, if you for example drag a picture from the iPhoto window onto a terminal window, you get the absolute path of the image as output. So throwing pictures from the iPhoto window onto the enlarger window will hopefully be possible with the next release.  
(Version 0.8)

STEVEN GOODHEART  Wow, drag and drop would be a great solution for now! Thanks for looking into that as a future upgrade possibility. For now, I'm just doing exports from iPhoto on stuff I want to work on in ImageEnlarger, and then go from there. ImageEnlarger is way cool. Thanks for creating it.  
(Version 0.8)

ARVIDTP  Actually you can drag and drop from iPhoto because SmillaEnlarger uses the native file open dialog. Just do Cmd-O and then drag your image from iphoto onto the open dialog box. Then hit return. I use this little known technique for all kinds of apps that otherwise don't support drag-and-drop. (It's also really handy if you want to save something in a folder that is already open in a finder window)  
(Version 0.8.9)

STEVEN GOODHEART  ARVIDTP, thanks for the way cool tip! Not only good here, but for other apps, too, as you say. Really, really useful! Thanks for taking the time to post. Steve  
(Version 0.8.9)

MLUSTECK  Since SmillaEnlarger 0.8.5 you should be able to drag and drop from iPhoto directly onto the enlarger. ( Works at least with my iPhoto 5 and Tiger ).

And if you drop a batch of photos they are batch-processed ( since 0.8.9 - for details read Help )

( Don't forget to uncheck 'Use Source Dir' or the enlargements are put into the depths of the iPhoto library ).  
(Version 0.8.9)

STEVEN GOODHEART  Thanks! I did notice that great change -- really increased the functionality of SmillaEnlarger for me, and others, too, I'm sure. That tip about unchecking "Use Source Dir" is one I didn't notice, until I buried a few files, so thanks!

This is a tremendously useful free app -- many thanks!  
(Version 0.8.9)

DAWGDRUMMER  I agree...how do you save the enlargement? I may be missing something but I don't see a way to save.  
(Version 0.8)

MLUSTECK  It should create a file with the name and location given at the bottom line of the window. By default "_e" is appended to the source name and the enlarged image placed to the same folder as the original. One reason why this doesn't work might be that at the moment calculation is aborted when you change something ( selected preview, clipping ) in the window. So you could try to do nothing until calculation is finished. If this doesn't work a serious bug might be involved. ( On my Mac Mini G4 saving works )  
(Version 0.8)

DAWGDRUMMER  The image is saved in the source folder but it is not enlarged.  
(Version 0.8)

MLUSTECK  If the enlarger really created a new file, it should differ from the original, unless zoom is at 100%. But you will not get just the 400x400 pixels shown in the preview but a magnified version of the complete image visible in the left "Source Clip" view. If you only want to enlarge a part of the source, mark it ( with left mouse-button down ) in the "Source Clip" view. After releasing the mouse, the left view should show the chosen clip of the source, and "Calculate" should render the enlarged version of the selected clip.  
(Version 0.8)