Software : Tutorial: Tilt-shift editing explained

Posted:

Tilt-shift editing explained

Special effects in photography tend to be a mixed bag. It can be difficult to create realistic-looking effects, much less effects that look like they were made in-camera, instead of through a digital editing process.

Tilt-shift editing is an example of a process that produces images that look radically different from their originals, yet could still conceivably have been made without a computer.

Tilt-shift has its roots in architectural and landscape photography, but in photographic communities, it has become a by-word for a style of photography that makes its subjects look like toys. Tilt-shift photography is beloved by its practitioners, partly because it offers a fresh new perspective on old and familiar scenes; it's difficult not to fall in love, for example, with an image of a favourite destination when it looks like it should be inhabited by Noddy and Big Ears.

Faking a tilt-shift image also takes mere seconds once you've got the hang of it, and can even be automated entirely, to the point that some compact cameras and even a few DSLRs come with the ability to miniaturise shots without the help of a computer.

For everyone else, creating miniature photos is a doddle, but as with producing any decent image, a little forethought and effort are required to achieve a good result. Read on to find out exactly how it's done.

Choosing your shot

With the digital process taking a short time, choosing your shot is the most crucial aspect of creating a rewarding and convincing tilt-shift photo. The best ones work if you imagine that you're trying to create an image of a small-scale model city. That means you need to imagine the angle from which you might shoot if you were standing over such a model - not directly down, but not directly at the scene, either.

A relatively shallow angle will help with realism - think pedestrian bridges or low-rising hills. Be mindful of exactly what you choose to shoot as well. It's possible to create a convincing tilt-shift image that includes people, but it's trickier to get right than shots of vehicles, for example.

If the people in your shot are too detailed, you'll lose the air of a Hornby-style model, so try to capture people from a long way away - go for rough shapes rather than facial features. Alternatively, objects that make popular toys are a good bet: construction equipment, trains and aircraft are all good potential ideas.

Truck

These are quite specific rules, but toy-style processing won't work very well unless you follow them - standard architectural shots and everyday portraits are likely to be poor candidates. If nothing else, this is a great excuse for you to grab your camera and get shooting some new subjects.

What you'll need

As ever, if you have access to the full version of Photoshop, you're laughing - you've got all the tools you need to create repeatable, convincing miniatures, and once you've practised doing it a few times you'll be able to get the job done in a few seconds.

Those unwilling to splash out nearly £700 on Photoshop CS5 need to get a little more creative. For example, it's possible to achieve the same result using Photoshop Elements, albeit with a few restrictions. For the best effect, you'll want to use a graduated mask, which you can't do in Elements.

To get around this restriction, we'll use GIMP, which has more or less the same range of editing tools as Photoshop, and is free, although its interface is a little less intuitive than Adobe's.

There's bad news if you'd prefer to stick with album-slash-editors like Google Picasa. Despite tilt-shift's popularity as an effect, it isn't available as a one-click option in many applications.

You can knock up quick and dirty tilt-shift style images online, using a service like www.tiltshiftmaker.com, which lets you upload your images. You can then apply an automated tilt-shift effect before downloading the finished result, although high-resolution images attract a charge of around 10 pence.

How to create your tilt-shift image

before

The file you choose can be virtually any format, although the two you're most likely to see are RAW and JPG files from your camera. Working on RAW file will pay dividends in terms of how much editing you're able to do, particularly when it comes to editing the colours in your image.

If you decide to work on a JPG, the first thing you should do is save your original file as a different format, such as TIF. Not only does this protect you from making an irreversible change to the original file, but using a lossless format is best for your workflow.

Otherwise, every time you tap [Ctrl]+[S] to save, you'll lose a tiny amount of detail from your file. This won't be noticeable the first few times, but after a while you'll have a file that won't print as well as you might like at high resolutions.

Otherwise, as long as you have a picture in your mind of the final image you want to produce, creating miniatures from photos doesn't need to take long at all.

After

The effect of miniaturisation on an image is similar to the effect you can get from a tilt-shift lens. This type of lens allows the photographer to place the focal plane of a camera at an angle to the sensor. Traditionally, this means you can correct perspective distortion if you're looking up or down at something, but it also means you can be extremely precise about which parts of your image are in focus.

This lets tilt-shift users throw the top and bottom of their images out of focus, leaving just a sliver of detail in focus. This is much like the effect you get when you take a picture of a model building or city, fooling your viewers.

Completing the effect

Using miniaturisation effectively doesn't stop at creating a new depth of field effect, though. You have to think in terms of how a model is constructed and what it might be made of. Using realistic colours will ruin the illusion, so while it might be best practice to create a true-to-life image, this is one area in which you'll want strongly saturated colours to help maintain the illusion.

Create a miniature photo in GIMP

1. Pick the right shot

step 1

A bright, panoramic image like this is the perfect candidate for the miniaturisation treatment. In GIMP, the process revolves around the Quick Mask tool - a speedy way of creating a selection area that follows a particular shape or pattern.

In this case we'll create a selection area that fades in and out, then blur the rest of the image.

2. Create a Quick Mask

step 2

Go to 'Select', then 'Toggle Quick Mask', or press [Shift]+[Q]. The whole image will turn red - this is the area that will be affected by your next change.

Choose the Gradient Fill tool (L) and, under 'Shape', select 'Bi-linear'. Click and drag the mouse down across the area of the image you want to be in focus.

3. Gaussian blur

step 3

Press [Shift]+[Q] to exit Quick Mask mode - you'll see lines of marching ants denoting the selected areas. To simulate depth of field, click 'Filters', then choose 'Blur | Gaussian blur'.

A bit of experimentation will help - start with the blur radius set to around 50, and don't be afraid to tap [Ctrl]+[Z] to undo your work and try again if need be.

4. Adjust curves

step 4

Without saturated, fake-looking colours your image won't quite come together. Go to the menu and choose' Colours | Curves'. In the resulting dialog box, click on the straight diagonal line and drag it into an S-shape.

For once, subtlety takes a back seat to effectiveness - don't stop until you've got a striking effect.

5. Fine-tune levels

step 5

Choose 'Colours | Levels'. Choose the chart named 'Input levels' and drag the two pointers under the chart towards each other. The further in you drag the left-hand pointer the darker your image will be, and vice versa with the far right slider. You want punchy colours, so being heavy handed with the left-hand slider is a good thing.

6. Finish and save

step 6

Hit 'OK' in the 'Levels' box and your changes will be applied to the image. Assuming you're happy with the result, press [Shift]+[Ctrl]+[S] to output your shot as a finished file. This isn't a one-size-fits-all process: some of your image will look better with more subtle handling, or with wider or narrower blurred areas.

Yahuui Blog

Sunday, October 16, 2011