I was asked recently how to get sharper photos so thought I would offer my thoughts and the practical considerations I adopt to make the most of each and every photographic opportunity.I have approached the question of sharpness by breaking it into five areas, namely, accurate focusing, camera support, mirror lock up, lens consideration and choice of ISO. These considerations are part of my photography workflow and thought process which will hopefully show you how to get sharper photos.
1. Achieving Accurate Focus
Focus is a critical point when considering how to get sharper photos. Whilst auto focus is generally reliable I prefer only to use the centre point, the remaining focus points in my opinion are less accurate.
Depending on the subject matter it is necessary to select the correct Auto Focus Mode. There are a number of considerations, namely:
Still subjects: ie. landscapes, portraits, still life etc. When shooting these type of subjects I would select the Auto Focus ‘ONE-SHOT’ setting. Simply place the centre point on the subject and press the shutter button part way to achieve focus, then press fully to take the photo.
Alternatively, I would auto focus on the part of the image that I want sharp, partly depress the shutter button to lock the focus and the recompose if required. You may wish to use this technique if you wanted the ‘sharp’ subject to be off centre within the photography composition.
Moving subjects: At times when the subject to camera distance is changing I would select the AI SERVO setting. This is a perfect choice to use for birds in flight for example, just hold the button down halfway whilst keeping the focus point on the subject and the camera will continuously re-focus as the subject moves.
Manual Focus: For certain subjects, particularly close up / macro work I prefer to switch off the auto focus and revert to manual focus. As the depth of field will be so shallow in close up photography it is a critical consideration. I find using manual focus is a more accurate and certainly an easier approach to finely tuning the precise point of focus.
2. Camera supportUsing a camera support, whether it is a tripod, a monopod or just resting the camera on a boulder or fence post, will always improve the chances of achieving sharp, highly detailed photos.
Whilst a solid, heavy tripod is best it is not always practical so any form of camera support is better than nothing.
Virtually all of my landscape photography is done with the camera firmly mounted on a tripod. When using the camera on a tripod it is important to ensure that any lens image stabilisation is turned to the off position.
3. Mirror Lock Up
Mirror Lock Up is the perfect partner when using a tripod. Virtually all SLR cameras have a mirror which must be moved out of the optical path before a photograph can be taken.This movement of this mirror, especially as it ‘slaps’ to a stop causes vibrations which move the camera / lens setup. These vibrations can often lead to a loss of image sharpness. This is especially true when using long telephoto lenses, in closeup / macro photography or using shutter speeds between 1/8th and 1/30th second.
When using Mirror Lock Up the mirror flips up and there is then a 1 or 2 second delay before the shutter trips, so this allows time for the vibrations have dissipated before the photo is taken. Using a cable / remote shutter release in combination with Mirror Lock Up and a tripod will further help.
4. Use the ‘Sweet Spot’ of the Lens
How to get sharper photos from the lenses you own. All lenses, either fixed focal length or zoom, have a ‘sweet spot’ which is generally in the mid range of the available aperture settings of the lens. To get the best from your lens it is generally best to choose an aperture between f8 to f11 to produce sharper photos. If you are shooting landscape photos with wide angle lenses this still applies though an understanding of Hyperfocal Focusing would be an advantage to maximise depth of field for this particular aperture range.
If you are using zoom lenses then the mid range focal length will produce the sharpest photos, so for example selecting 60mm on a 24 – 105mm lens will bring the best out of the lens resulting in sharper photographs.
5. Choice of ISO Speeds
My philosophy on ISO choice is to choose the lowest (slowest) ISO to complete the job. So if taking photos of still subjects, say a landscape on a tripod for example, I would choose 100 ISO, if there is no choice other than hand holding in low light then I would choose a much higher (faster) ISO.
With the improvement in noise control on newer digital cameras the issue of ISO is slightly less of a problem. I have achieved very acceptable A3 size photos from my Canon EOS 5D mkII using speeds as high as ISO 1600, so it is worth experimenting to see how far you are prepared to push the ISO to suit your requirements.
If hand holding the camera it is important to ensure a shutter speed equivalent to the reciprocal of the lens. So for example, a 50mm lens requires a shutter speed no less than 1/50th second whereas a 500mm lens requires a speed no less than 1/500th second. So if the aperture (depth of field) is a priority then the ISO can be used to tweak the shutter speed to meet this requirement.
Conclusion – How to get Sharper Photos
Obtaining sharp photographs is a fundamental requirement, it is an important skill to master and useful addition to your photography skills toolbox.
However, there may also be times when art and creativity need to be let lose, when we can throw of the shackles for the quest for sharpness. Here are such photos, these are taken from my Seascape Impressions portfolio.
If you found this interesting it would be good to hear your thoughts, feel free to leave a comment or share with your friends.