I was taking pictures long before digital cameras came along, and I’ve got a large collection of 35mm transparencies and black and white negatives. I’ve even managed to scan them all in at those odd times when I’ve had film scanners in for review for magazines. The trouble is that not only are some of my pictures skewed, the film holders for film scanners can often add a skew of their own.

Aperture Crop and Straighten tools

Here’s an example! I must have been standing in some quicksand when I took a picture of this seaside pier and, even though you probably can’t see it here, the scanner I used had a film holder that didn’t quite keep my trannies straight either.

Now I don’t usually bother straightening and cropping while using a film scanner because the whole process takes long enough already, so I aim to do it when I’ve imported all the pictures into Aperture instead. And this is how I fix them using the Aperture Crop and Straighten tools.

01 Two skews in one

Aperture Crop and Straighten tools

There doesn’t seem much point in straightening up the scan to line it up with the transparency mount edge and then straightening it all over again to get the horizon level, so I’ll just use the Straighten tool (circled) to get the horizon level. While the mouse is down Aperture displays an on-screen grid which makes this easier.

02 Crop tool aspect ratios

Aperture Crop and Straighten tools

Now I need the Crop tool now (circled on the bottom toolbar), and I also need to choose the aspect ratio – the ratio of the picture’s width to its height. I could set this to ‘Do Not Constrain’ so that I can keep the maximum possible image area, but my experience of 35mm slide mounts is that they mask off more height than width, so unconstrained crops end up a little too wide. I’ll stick to the spirit of 35mm film and go for the 2 x 3 option (35mm film’s native aspect ratio).

Don’t worry if that sounds like the picture will be taller than it is wide – Aperture’s Crop tool automatically adapts to the shape you drag out, so I do get a horizontal crop in this instance.

And bear in mind that the 2 x 3 setting is the ratio, not the actual size. Aperture isn’t going to resample your image into a smaller version, even though it does display (4 x 6) alongside – that’s just a reminder that this ratio fits classic 4 x 6 prints, not that you’re going to get one that size.