I suppose really it depends what you wish to do with the pictures, if it's for inclusion in a book then let the publishers sort it out, if it's just that you want to get them onto your computer so you can use them for posting on the web etc then accept they will never be perfect and either lash out £500 or so on Photoshop or as Milo suggests use Gimp which, as he says, is a bit quirky but is nearly as good as Photoshop for things such as spot healing, and I think you can get a less quirky 'Photoshop' lookalike GUI for it, looking at the photo it would take only a few minutes at the most to remove those few blemishes, and also touch in the 'rope' effect around the captain and first officers feet. Do all the repairs and adjustments before using the sharpening tool if you feel you need it.