An issue a lot of beginning aviation photographers face is coming home after a day of spotting to find that their images from the day are alarmingly soft and perhaps low in contrast. What can you do to save them? The answer is not much really; the Smart Sharpen tool in Photoshop can only do so much before it starts to ruin the image with noise. Sometimes images that are shot too poorly simply cannot be saved, as poor quality going into Photoshop means poor quality coming out. The only solution is to start shooting better, and my quick tips on how to get sharper images should help you with that.
The weather and conditions outside in your shooting environment affect image sharpness more than many people realize. If it’s a polluted day or the lighting is soft, then your images will also be soft. There’s no way to fix or compensate for bad weather other than avoiding it as best as possible. See my guide for how to determine spotting conditions at your local airport.
Distance to subject
The general trend for all types of photography is that the farther you are away from your subject, the softer your image will be. You may have noticed this playing around with your camera, and it is due to two reasons. First of all, a far away subject means that light has to travel a greater distance from the subject to your camera. This will degrade image quality as the light has to pass through particles in the air that will distort its path. The second reason is that generally you will need to use a much longer focal length for a subject far away. This is very unfortunate because most telephoto zoom lenses rapidly lose sharpness as they zoom in. Therefore you should always try to spot from a location that is closest to the aircraft.
This one is definitely a no-brainer and I realize that not everyone can afford top-of-the-line gear, however the difference that better quality glass can make in terms of image sharpness is quite phenomenal. At the same time, just because a lens costs more than another doesn’t mean it’s necessarily sharper. Be sure to check out DxOMark for in-depth statistics for different lenses. Always do plenty of research and buy the sharpest lens that suits both your needs and your budget.
Any normal camera lens, wide angle or telephoto, prime or zoom, will be soft wide open at its maximum aperture. Lenses are not designed to always be shot at maximum aperture, and need to be stopped down for maximum sharpness. Most telephoto lenses have their sweet spot at somewhere around f/7.1 or f/8, where they are the most sharp. Obviously you’ll need quite a lot of light to shoot at such an aperture, but that won’t be a problem as long as you’re spotting in the day with suitable lighting conditions.
Most of the time image softness is the result of a slow shutter speed. Even the smallest vibrations from something like the mirror flipping up will cause minute amounts of camera shake that we see as softness. When using telephoto lenses, your shutter speed should be at least double your effective focal length. 20omm on a full frame equates to at least 1/400, and the same focal length on an APS-C camera requires at least 1/640. Anything slower and all the vibrations from your hand and your camera will cause camera shake and blurriness. If you have an image stabilized lens, then you will be able to shoot with slightly slower shutter speeds. In general, I would say that your shutter speed for photographing planes in flight with a telephoto lens should never dip below 1/400.
There are my five quick beginner tips for how to get sharper images. If you’ve followed them correctly, then your pictures should come out razor sharp. If not, email me at firstname.lastname@example.org if you have any questions. Good luck!