By Peter Stewart | 16 Feb 2014
Here are a few tips that should be kept in mind when editing any image. This is tailored for those using Adobe’s Lightroom or Photoshop as their image editors.
Removing chromatic aberrations
Commonly known as “colour fringing”, chromatic aberrations are caused by the way your camera lens focuses the different wavelengths of light onto the focal plain. A lens won’t always focus colours into exactly the same place, leaving you with those nasty green and purple lines around edges. This problem usually plagues wide angle lenses and is more prevailant in high contrasty light. It is especially problematic with wide aperture lenses.
Luckily, this can be easily cured with a simple little tick box.
Both Photoshop's Cameraraw filter and Lightroom have a simple means for removing colour fringing, by analysing the EXIF data in your image file for information on the camera and lens combination used, to correctly remove the fringing. This simple fix should be left on by default.
Removing Image Halos - Photoshop
A very common side effect of HDR processing or sharpening is white halos around edges, caused by lighter pixels meeting darker ones. Here’s a simple fix to erase those white glows without compromising your image.
- Firstly you will want to zoom in to around 150% to the affected area
- Create a new layer
- Select the ‘Clone Stamp’ and dial in the opacity to around 50%
- Set the 'Mode' to 'Darken'
- Select an area of the image next to the haloed area which we want to use as the replacement area for painting over by holding down (PC - ALT+Click, Mac - Option+Click). For example, in this image I have a halo between the brighter sky area and the darker edges of the building. I will select the sky to paint over the white halos.
You may have to paint over the halos a few times to reduce the effect, or increase the opacity to around 80% to completely remove them.
This method works great
Removing Dust Spots
If you're shooting with a DSLR, and change lenses often enough, eventually some dust and dirt is gonna creep in there and attach itself to that lovely expensive sensor. For the most part, it’s unnoticeable unless you are stopping down to smaller apertures, however if you're getting these circular specks ruining that perfect sunset shot you took, here is the simplest fix available.
Photoshop - Open your image in CameraRaw and select the 'spot removal' tool. Double click on the affected areas and just like BAM, the dirt is gone!
Lightroom - Under the 'Develop' tab, second icon in. Make sure it's set to 'heal' and start selecting areas to fix.
Well there isn’t much to say on this topic as it should be a no-brainer, but wonky horizons or skewed portraits are often overlooked in the editing suite.
Things like utilising the rule of thirds and cropping are all part of creating a better look to maximise the visual impact, but they are artistic rules that don’t always need to be followed.
Straightening however, should always be taken into account when editing, as a wonky horizon will quickly diminish all other positive qualities an image has.
Digital noise (not to be confused with lovely lovely film grain) is not all that pleasant to look at. Besides high ISO images, if you have to bring out shadow detail in an image, you are unfortunitly bringing out more noise detail.
For a quick and dirty fix though, Photoshop and Lightroom do have a quick tool available for reducing noise, but more importantly, removing colour noise which is usually seen in High ISO images.
Photoshop - Open image in CameraRAW. Goto 'Detail' slider and slide the 'Luminance' slider to the right until any white speckles are gone. Too much and the image will lose it's sharpness. Compensate by playing with the sharpening 'amount' and 'detail' sliders.
Secondly, drag the 'Color' slider to the right until any hints of colour noise are rectified. This is invaluable with high ISO images and on occasions where shadow detail has recovered at the expense of adding in noise.
Lightroom - Click on the 'Develop' tab in the top right to access editing features. Open up the 'Detail' tab and you will notice the same sliders that are featured in Photoshop. Just apply the same rules here to fix up any noise.