Export sharpening is a setting that’s often overlooked when you generate images for online or on-screen viewing, but it makes a big difference to how sharp your pictures look.
Every time you resample an image, you introduce a degree of blur because the software has to interpolate new pixel values – and this applies when you’re downsizing images for web use too. In part 1 I compared the results from Aperture (which has no export sharpening), Lightroom (which does) and the dedicated Perfect Resize plug-in. It was quite an eye-opener!
In part 2, I want to find out whether the same applies for DxO Optics Pro 9 and Capture One Pro 7. I’ve used the same test, and the same image I used last time (above), exporting the full-res file at a height of 1024 pixels for web use. Here’s what happened.
01 DxO export settings
DxO Optics Pro 9 offers different resampling options when you export a file – if you’ve used Photoshop or Elements to resample images, you’ll recognise them straight away. They’re on the drop-down Interpolation menu, which I’ve circled in red. These aren’t sharpening tools – this menu simply changes the way DxO Optics Pro calculates the pixel values.
02 DxO Auto vs Bicubic vs Bicubic sharper
And here you can see the results (remember – you can click on these images to see a full-size version). The default Auto result is on the left, and you might expect this to automatically choose the best resampling method for the size change being applied. In fact, though, it’s only marginally sharper than the Bicubic setting, shown in the centre.
Bicubic resampling is a kind of default amongst image-editors. It gives reasonable results for both enlargement and reduction, but favours smooth tones rather than sharp detail.
Bicubic sharper is designed specifically for resampling images downwards, and this image, right, is much sharper than the other two. If you’re exporting images for on-screen or online use, this is the one to go for.
03 Capture One sharpening
Capture One Pro 7 can also export images at different sizes, but doesn’t offer a choice of interpolation options. However, if you open the Process Recipe panel and click the Adjustments section, you’ll see there’s a Disable Sharpening checkbox. This is enabled by default, but I’ve deselected it for the test below to see what different it makes.
04 Capture One sharpening vs no sharpening
Now I don’t know about you, but I can’t really see any difference! It’s possible that this checkbox has no effect with this downsampling process, but I would like to test it on another image to make sure.