This one came from a request from the “Ask a question” page. A reader was wondering how you convert negatives inside of Aperture. I immediately thought to myself, what an interesting question! There’s no “invert” adjustment and no negative presets built in. In the immortal words of Barney Stinson – “Challenge Accepted”!
Of course, it’s easy enough to invert an image using the curves tool, but there’s more to it than that, as negatives have an orange backing and are not just an inverted positive. So I dusted off my old film scanner that I haven’t used in quite a while, and after searching for a while to find all the parts, and to find compatible software to get it working under Lion, (thank you Vue Scan) I scanned some negatives and worked out the best way to do it. It was actually a lot more difficult than I thought it would be but in the end I was able to re-create what I believe is near enough to the correct results.
Here’s the thing though – you shouldn’t have to use this. If you’re scanning images yourself, you should always use your scanner’s “negative” function. This has the necessary colour adjustments built into the software and you will end up with a positive image. Most, if not all scanners capable of scanning film should have this function. Still, I can concede that you might have some images that were scanned incorrectly and you need to fix them, so feel free to use these presets – but be aware that they are not the best option.
I’ve taken some scans of some old film I had (from 1997 I believe) and they’re of noting particularly interesting, but it should give you an idea. For the purposes of this excersise I scanned them twice, once as a positive, and again correctly as a negative. I then used the correct negative scan to use as a reference to get the image right
Here’s a negative scanned as a positive
Here’s the same image, scanned as a negative using the scanner’s built in negative function.
Here’s the result of my adjustments in Aperture to “fix” the first image above to be correctly displayed.
Here’s another example – this one has been scanned correctly in the scanner software…
…. and here’s the Aperture version using the preset to correct a version with the negative scanned as a positive. Confused yet?
I’ve created these through guesswork and eyeballing the result too so your mileage may vary. I’ve two presets included in the pack – each with varying strength. They seem to work well, but I can’t guarantee anything.
Another thing to bear in mind is that I’ve used a curves adjustment to invert the image, so if you’re making adjustments, anything you change above the curves adjustment in the hierarchy will have the opposite effect. For example, playing with the recover slider will actually increase the blacks and so on. I hope this is of help, and please let me know if you use these and they are of some help.