How can I resize a photo to approx. 1200 x 1200 and 72 dpi

SusCo,

you can create your own custom export Presets.

In the "Export" panel select "Edit".

And then select one of the presets you want to modify and press "+" to create a new copy.

Now you can select a custom pixel size or dpi setting, add a watermark, change the jpeg quality.

Set "Size to" to fit with 1200 pixels, if you need that size and rename the custom preset

Just keep in mind that Fit within may not give you the desired effect you are looking for if the original image is not at the same aspect ratio as the dimensions you use in the fit within box.

You may want to crop the image first to the desired aspect ratio before exporting so that the final image fills the frame.

You don't resize within Aperture. You would need to export a file.

So export it and define the size and DPI you want as part of the export.

You're welcome! 🙂