Digital Photograph Enhancement
Generally images from a digital SLR camera need to have some post-processing done to them. The amount of post-processing really depends on the quality of lens that you use, quality of the image that you have taken, personal preference, and what you intend to use the image for.
You can adjust the 'processing parameters' in a DSLR camera so that the camera automatically adds contrast, sharpness, saturation, and colour tone to the photograph as it is captured but it is generally accepted that it is much better to set the camera's 'processing parameters' to standard and enhance the photograph using an image editing software such as Photoshop Elements or Paint Shop Pro to do the post-processing.
Using RAW mode for the image-recording quality on a DSLR will allow you much more latitude in post-processing with the ability to alter the exposure, white-balance, colour, and sharpness etc. but file-sizes using RAW mode are much larger, meaning less photos can be stored on your memory card, than using Large/Fine JPEG mode. For this article i am going to assume that you have taken a photograph which has good exposure, is sharp, and is taken using Large/Fine JPEG mode (highest quality JPEG mode i.e. not RAW mode)
Firstly it is a good idea to make sure that your monitor is correctly calibrated. A Google search will find many websites that help with monitor calibration or a calibration device such as the Spyder 2 can take the guess work out of calibrating your monitor.
Make sure your original images are backed-up and only work on copies of the original image.
Digital Photograph Workflow
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A basic workflow might be something like this:
CROP
RE-SIZE
ALTER BRIGHTNESS/CONTRAST
SHARPEN
SAVE
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A more advance workflow might look like this:
STRAIGHTEN IMAGE
CROP
RE-SIZE
REMOVE DUST SPOTS
LEVELS
CURVES (if required)
HUE & SATURATION
SHARPEN
SAVE
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The basic workflow is rather simple but can be done very quickly. Below i will show you step-by-step how to do the more advanced workflow:
STRAIGHTEN IMAGE:
Straightening an image is usually only necessary when you take photos of aircraft on the ground or as they take-off & land. You see many photos of aircraft landing, where the aircraft is horizontal but the runway and background are sloping, causing a very unnatural look to the image.
It is very easy to put this right using Photoshop Elements or Paint Shop Pro. The 'Free Rotate' tool can be found in the IMAGE menu and can be used to rotate the image a few degrees left or right.
The hard part is knowing what is level and the best way to do this is to look for vertical lines in the image such as houses, posts etc and rotate the image until these are upright.
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Sloping horizon
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RE-SIZE:
The RE-SIZE tool can be found in the IMAGE menu at the top of the screen for both Paint Shop Pro and Photoshop Elements.
This tool allows you to re-size the image in pixels or alter the 'Document Size' in inches/cm.
If the image is intended for use on the internet to be viewed on a monitor then a width size of 800pixels or a maximum of 1024pixels is usually the standard. The 'Resolution' should be set at 72 pixels/inch or no more than 96 pixels/inch (depends on screen resolution settings & monitor screen size). Setting the 'Resolution' higher than this is a waste of time for viewing on a monitor and will result in a large file-size with no improvement in quality.
If the image is intended to be printed then you can alter the 'Document Size' to the size you wish to print (say 6 inches by 4 inches for a standard print).
You should set the 'Resolution' to at least 300 pixels/inch which is usually standard for printing or sending for publication. Also, before printing, select 'Print Preview' in the FILE menu, so you can preview the image and make sure it fits the paper.
Make sure that the 'Constrain Proportions' box is ticked so that altering the 'Width' size proportionally alters the 'Height' size, otherwise you will get a squashed image.
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Resize
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REMOVE DUST SPOTS:
Removing Dust-spots from an image usually requires the use of the 'Clone' tool which looks like this:  or 
This tool allows you to sample an area of the image near to the Dust-spot and to clone that area to cover the spot. Alternatively you can use the 'Heal' tool instead of the 'Clone' tool.
Dust spots are unfortunately commonplace when using a Digital SLR camera. They are caused by dust collecting on the camera's sensor usually when you change lenses. If you have a lot of dust spots then you will need to clean your camera's sensor.
It is quite difficult to see Dust-spots on an image so the best way to view them is to 'Equalize' the image which will highlight the spots.
'Equalize' can be found in Photoshop Elements in the 'IMAGE' menu. In Paint Shop Pro go to the 'COLORS' or 'ADJUST' menu. To use the 'Clone' tool in Photoshop Elements, select an area near to the Dust-spot using alt- left click or when using Paint Shop Pro then right-click. Make sure the brush is large enough to cover the Dust-spot and clone out the spot. Below i will show you a procedure to remove Dust-spots from the image using 'Equalize', 'Layers', and the 'Clone' tool:
First we must 'DUPLICATE' the image (look in LAYER menu).
We now have 2 layers 'Background' (original layer) & 'Backround Copy' (duplicated layer).
Next we EQUALIZE the 'Background Copy' (duplicated layer).
Now make sure you select the 'Backgound' (original layer).
We can now CLONE out the Dust-spots using the CLONE tool.
Note that you will NOT see the Dust-spots being Cloned out because we have the 'Backgound' (original layer) selected.
Now, Delete the 'Background Copy' (duplicated layer) and you should be left with the original layer which is free of Dust-spots.
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Equalized image.
Layers.
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LEVELS:
If you are using Paint Shop Pro then select LEVELS (ADJUST menu) or if you are using Photoshop Elements then select LEVELS (ENHANCE menu).
LEVELS shows three pointers/sliders underneath a histogram. The actual histogram represents the tonal range (contrast & colour balance) of the image with the left showing darkness, the right side showing lightness, and the middle showing mid-tones. Generally, an underexposed image would have the pixels bunched up to the left and an overexposed image would have the pixels bunched up to the right. LEVELS is a quick and easy way of manipulating the image to get the desired exposure and unlike CURVES will not usually give an unnatural looking image.
The easiest way to use this tool is to move the left slider to the left of the histogram curve and the right slider to the right of the histogram curve. Now you can move the centre slider right or left to lighten or darken the whole image. You may wish to experiment with the sliders until you are happy with the result.
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Levels
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CURVES:
The CURVES tool can be found in Paint Shop Pro (COLORS or ENHANCE menu) but you may not have it if you have Photoshop Elements.
CURVES will allow you to adjust the image tonal range like LEVELS but will allow you much more subtle control to fine-tune the image. However, it is easy to over-use this tool and end up with an unnatural looking image, so be careful.
You start with a box containing 16 squares with a straight diagonal line running from the bottom left to the top right. By clicking on the line you create points which can be moved to create a curve which alters the contrast etc of certain parts of the image. You can actually click on part of the actual image with the eye-dropper tool and this will place a point on the curve which directly affects that area. Again, experiment with this tool until you are happy with the result.
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Curves
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HUE & SATURATION:
The HUE & SATURATION tool can be found in Paint Shop Pro (COLORS or ENHANCE menu) and Photoshop Elements (ENHANCE menu).
HUE & SATURATION will allow you to enhance the image with a bit more colour, if it needs it.
Increase the Saturation slightly and this should bring out the colour in the image a little more. You can also try REDS, YELLOWS, BLUES etc rather than just using MASTER. Experiment until you are happy with the result but do not over-use or you will spoil the image.
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Hue/Saturation
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SHARPEN:
The SHARPEN tool can be found in Paint Shop Pro (EFFECTS or ADJUST menu) and Photoshop Elements (FILTER menu).
The SHARPEN tool that we are going to use is Unsharp Mask (USM) as this offers much more control then the standard sharpen tool. In Photoshop Elements there are three controls called AMOUNT, RADIUS, and THRESHOLD and the equivalent controls in Paint Shop Pro are STRENGTH, RADIUS, and CLIPPING.
The way Unsharp tool works is by exaggerating the light-dark contrast either side of all the 'edges' making the image appear sharper. The RADIUS specifies how large the region around the 'edge' will be while the STRENGTH/AMOUNT is how much this region is adjusted (dark pixels made darker, light pixels made lighter). Lastly the THRESHOLD/CLIPPING defines when an 'edge' is considered to be an 'edge' and is acted upon.
Now, we need to know what values to put in these three controls. Everyone uses their own values and so it is really down to personel preference.
Hovever, the important thing is that we end up with an image that is sharp but has not been oversharpened and results in jagged lines. I tend to use STRENGTH/AMOUNT 50, RADIUS 0.3, THRESHOLD/CLIPPING 0 as a starting point but if you need more or less sharpening then increase/decrease STRENGTH/AMOUNT. If you intend to print your image rather than view on the monitor then you may need to increase the RADIUS control.
I will show a procedure below for selective sharpening so that you can sharpen the aircraft but leave the sky unsharpened.
This will involve using the 'Magic wand' tool which looks something like this:  or 
Select the 'Magic wand' tool and click on the sky. You may have to hold down the 'Shift' key and keep clicking on the sky until you have all the sky selected (see picture on right). You can also alter the 'Tolerance' control to fine-tune your selection.
Next we need to select the aircraft rather than the sky. We do this by selecting 'Invert' (Paint Shop Pro - SELECTIONS menu) or 'Inverse' (Photoshop Elements - SELECT menu).
Now, by using the Unsharp tool, we can sharpen the aircraft without affecting the sky.
Using this method, you can also use 'Layers' so that you add some sharpening then DUPLICATE (LAYERS menu) the image, then sharpen some more and DUPLICATE again so that you have Layers of different sharpness. Now, if you get some oversharpening on part of the aircraft then you can simply use the ERASER tool to rub out the jagged lines.
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Unsharp Mask (USM)
Magic wand
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SAVE:
Lastly, we SAVE (FILE menu) the finished image. It is a good idea to SAVE as a Paint Shop Pro file or Photoshop file so you can OPEN the image at a future date and be able to UNDO or alter the steps you used to manipulate the image. Otherwise, SAVE the file as a .bmp or .tiff file as it will then be saved without being compressed in any way.
If the image is intended for the internet/website then it is still a good idea to SAVE a copy using one of the above file formats but also you will need to save the file as a .jpg file. The .jpg file format compresses the image to a smaller file-size which is ideal for the internet/website. Photoshop Elements and Paint Shop Pro both allow you to save the image as a .jpg and compress the file by varying degrees. The higher the number that you enter then the more compression that is added and the smaller the file-size. It is just a matter of striking the right balance between a small file-size and an acceptable image for viewing on the internet/website. It is also a good idea to get into the habit of saving files so that the file-name is in lower-case letters. Some servers (UNIX) only accept lower-case file-names.
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Save
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This is just one method of improving photographs and many people have their own workflow. There are many more different ways to improve an image and certainly countless ways of sharpening an image. It is also worth mentioning that it is probably better to make all the above changes using LAYERS so that you always have the original image to fall back on. I hope this little article helps to inspire you to experiment with your photographs using Paint Shop Pro or Photoshop Elements.
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Crop
