Those people at nik multimedia know how to make great Photoshop plug-ins. Take Dfine - this inexpensive tool is great for tweaking images in order to make perfect prints. Digital noise, JPEG artefacts, colour and light can all be adjusted, and in many cases smoothed away.

The Dfine suite can work in one of three ways: Easy, Professional or Selective. The Easy mode is a simple one-click affair. Just choose the amount of effect from a drop-down menu, then click and let the software get on with it.

The Professional mode provides endless tweaking and tinkering opportunities, including an analysis mode and the possibility of using profiles. The Selective approach enables you to apply a filter to the whole image and then erase the effect in certain areas. You can also opt to paint in the effects from an unaltered state. It's perfect for reducing problems where they show up most.

Also part of the Dfine system are 'camera profiles'. You can buy a profile to work with Dfine that has been optimised to take account of the sensor characteristics of your camera. If, say, you have a Canon EOS 10D, the profile nik supplies will be custom-built to smoothe out the specific digital noise and JPEG characteristics unique to that model of camera.

The profiles are $39.95 - yes, it is an extra cost, but the time it saves you not having to tweak settings is worth it. If nik doesn't have the profile for your particular camera then you can request it.

If you take a lot of photos and are troubled by images with noisy skies or exposure problems, then Dfine is well worth a look. For producing optimised custom photo prints it really is worth investigating. Mark Sparrow