How do i stop Aperture automatically importing Raw files?

Are you shooting RAW + JPEG?

Automatic import to Aperture is enabled in Image Capture.

From the Image Capture Help:

1. Connect your device/card to your computer, then turn the device on.If the device is locked with a passcode, enter it.
2. In Image Capture, select the device in the Devices list.
3. Use the buttons at the bottom of the Image Capture window to view the thumbnails as a list () or to see larger thumbnails (), or to rotate () or delete () images.Drag the slider in the lower-right corner of the window to change the thumbnail size.
4. Click the Import To pop-up menu, then choose where to save the images or which app to use to open the image.
5. To import only some of the photos, select those photos, then click Import. To import all the photos, click Import All.
   • To automatically transfer images from your device to your computer whenever you connect it to your computer, click the Show Hide button in the lower-left corner of the window. Click the “Connecting this device opens” pop-up menu, then choose AutoImporter.
   • To remove items from the device after transferring them to your computer, select Delete after Import in the lower-left corner of the window.

i do not use image capture to import to Aperture.

The settings in Image Capture determine, which application is automatically opening and importing the images. You do not launch Image Capture for importing, but it is where you set the options which application will launch when you connect a camera and if the import is automatic.

You're welcome 🙂 I'm glad it worked for whatever the reasons were!