Using Acromats for astrophotography

So I am hoping to work and save a little money for a new telescope and some camping gear, more on that later. Right now I am looking into equipment for a new telescope rig. The interesting thing is that I have fallen in love with the Orion 120mm f/5 Achromatic refractor. Now this is for an astrophotography setup so you should be screaming that I need an APO. This is about 10x less than an APO because it has only two optical elements in the lens. The result being chromatic aberration. Now in the old days this would be a huge problem as you had no ability to process photos after they had been taken. You basically took the image on film and developed it and if there was the slightest error, you were screwed.

Digital cameras make the world a bit nicer. Here is an image taken by the telescope I am interested in: 

The original can be found here. (scroll to the bottom) The image has several issues, the focus seems off the tracking might be bad, but the thing we are going to deal with is the fact that its too purple. This purpleness the result of chromatic aberration, so I opened up the image in GIMP and used a filter I found called Darla's Purple fringe fix. Applying the default settings we get this:

Still not great but less purple. Interestingly Photoshop has this built in. If anyone from the gimp team is reading this, please implement that feature! Anyway I am hoping to post about my plans for astrophotography tomorrow.