How to use Photos to make subtle changes
Dust spots are the bane of SLR users’ existence. Here, two particularly fine splodges are ruining our shot. Click the edit icon to get the toolbar up. Click the sticking plaster icon on the vertical list of options, then drag the mouse over your dust spot.
The tool works by sampling a nearby area of your shot and copying it over your dust spot. To change where Photos samples from, Option-click the place you want to copy pixels from. Drag the slider, or press [ or ] to adjust the size of the brush.
STRAIGHTEN UP, FLY RIGHT
Wonky horizons are a regular issue in landscape photography, so hit the crop icon and click and drag the rotation wheel on the right-hand side of your image to straighten it up. The grid that appears should help you get the horizon straight.
Click Adjust for access to the really tasty tools. At first, you’ll only see Light, Colour and Black & White — the first two are layman’s terms for exposure and saturation, but click Add to see a list of other options.
ADD THE HISTOGRAM
A histogram is a useful way of assessing the changes you’re making. The graph is a representation of the brightness of your image: if all the wavy lines are clipped off the right side of the graph, your image is over-exposed. Vice versa and it’s too dark.
White balance is typically used when you’ve been shooting in mixed-light indoor environments, but it can be useful elsewhere. Dragging the temperature slider left will cool your image; the opposite direction warms it up.
This is what happens when you go big guns on the saturation sliders. A very dramatic image, but one that will, unfortunately, look pretty crazy if you try to print it. Keep your edits subtle for the best effects!
Add the levels tool, and click and drag the left-hand handle until it’s directly under the beginning of your histogram. Do the same for the right-hand slide. This will quickly get the darkest parts of your image black and the brightest bits white.
You can warm up an image using white balance, but using the Color slider is a great finishing touch to your edits. Use the drop-down arrow to break Color down into contrast, saturation and cast for more control.
GO BACK IN TIME
Click Done to save your changes (you can return to the edit screen at any point and click Revert to Original to restore your shot). Alternatively, select your shot and choose Export to create a copy with your edits for use outside Photos.