By Dimitrios Zavos
From photography enthusiasts to full-time professional photographers, image sharpness is often considered to be the "Holy Grail". An image which demonstrates clean lines, crisp details, no motion blur and with the main subject in sharp focus will always stand out and be more visually appealing than others that fail to display such attributes. There are two major factors that influence sharpness in photography and they are none other than:
The acquisition of Accurate Focus
The elimination of Camera Shake
In this article I will try to explain in simple terms how to achieve both of the above and give your images a tremendous boost in quality and a more "professional" look. So, without further ado, I present to you my Top 10 Tips to Super-Sharp Photos:
A rather sharp portrait of a Plumed Basilisk
A sturdy tripod is the one accessory that every self-respecting photographer should own. A common misconception is that a tripod is required only for shooting in low light conditions, where longer exposures are the norm, but the truth is it can transform your daylight photography as well.
Avoid extending the legs and central column of your tripod more than necessary, since the top-heavy structure will wobble easier the taller it gets.
When choosing a tripod, make sure you select one that has sufficient weight rating to support your camera and lens. Avoid cheap and nasty options like the plague. The last thing you want is your tripod collapsing with your gear on it.
A trick some photographers use is to hang a heavy load, usually a bag filled with rocks or even the camera bag, from the hook that some tripods have at the end of the column. This lowers the center of gravity and makes the tripod even sturdier.
There is a huge variety of tripods in the market; more than enough to cover all budgets. My suggestion is to find one with a spirit level on it so you can always be sure your camera is not at an angle to the true horizon.
When you are shooting hand-held and especially when using zoom lenses extended beyond 100mm, always try to apply what is known as the "Hand-Holding Rule". This rule states that "the shutter speed should be at least 1/focal length of the lens, or faster".
What this means is that if your lens is zoomed at 200mm, then your minimum shutter speed should be 1/200 sec in order to minimize the chance of camera shake appearing in your photo.
Be aware that entry to mid-level DSLRs (which are what 99% of beginner photographers will purchase as a first camera) have what is called a "crop sensor" and not a "full-frame" one. I will not go into detail about the differences between the two formats at this time, as this will be the subject of a future post, but the effect of the "crop sensor" is that the lens' actual focal length is derived by multiplying the lens' nominal focal length by the sensor's crop factor.
The crop factor for non-full frame Canon cameras is 1.6 and for Nikon 1.5 which means that a 70-200mm zoom lens would effectively become 112-320mm when placed on a Canon and 105-300mm on a Nikon camera. Thus, whenever a photographer is shooting hand-held with a crop-frame camera and has a lens zoomed at 200mm the aim should be for a minimum shutter speed of 1/320 sec (if the camera is a Canon) or 1/300 (if shooting with Nikon). All this may sound a bit confusing, but it really is quite simple once you grasp the principle behind it.
Check out our article on the effects of Shutter Speed in photography to gain a better understanding on the subject.
A high ISO setting can result in "noisy" or "grainy" images and loss of detail, as I explained in a more detailed post about ISO selection.
If you are using a tripod (or at least supporting your camera on a steady surface) and shooting still objects you should lower your camera's ISO setting to the lowest possible figure. This will result in longer exposures, but sharpness and image clarity will increase significantly, resulting in photos of much higher quality.
If you are shooting hand-held, then again aim to lower the camera's ISO setting to the lowest possible number that allows you to comply with the above mentioned "Hand-Holding Rule".
The selection of the right Aperture plays a major role in achieving optimal sharpness. Each lens has a different Aperture "sweet spot" where it achieves its maximum sharpness. For most lenses (especially non-professional ones) this occurs for Aperture values between f/5.6 and f/8.0. Always keep in mind though that changes in the Aperture setting will have a direct impact on your Shutter Speed and Depth of Field.
Usually, when shooting portraits, sports or macro, the photographer uses large apertures (f/1.2 to f/5.6) to blur the background and isolate the subject, whereas when shooting landscapes, where everything should be in focus, smaller apertures of f/8.0 to f/11.0 are the norm.
This is all explained in depth in our article about Aperture and Depth of Field.
If your lens or your camera have an Image Stabilization (IS) or Vibration Reduction (VR) function and you are shooting hand-held, always keep this option enabled. This is a system that detects and corrects slight camera shakes. Minute gyro sensors detect lens or camera vibrations caused by hand shake and send a signal to a microcomputer, which controls an IS (or VR) lens group that compensates for the pitch and yaw (movement along the horizontal and vertical axis of the camera). This function usually allows shooting at three to four stops lower than with a non-IS device.
On the other hand, when the camera is mounted on a tripod (or any other unmovable support) the IS system can be confused by the lack of movement and actually cause slight tremors as it moves around trying to detect movement. This is particularly true of older image stabilization systems, so it's preferable to disable IS completely when using a tripod in order to improve image sharpness.
The autofocus function may make things simpler and faster, but in challenging light conditions it can be a bit of a "hit and miss". Unfortunately, incorrect focus is impossible to correct in post-production. Moreover, manual focus through the camera's viewfinder is also quite inaccurate. Don't despair though, as there is an easy way out of this mess.
Most modern DSLRs offer the option of magnifying Live View (the live image projected on the camera's built-in screen) by up to ten times. This can work wonders for acquiring super-accurate focus. Simply mount your camera on a tripod, frame your shot, switch to Live View, switch to manual focus, magnify the image as much as possible and micro-adjust the focus to achieve perfection. Then fire at will!
Even when your camera and lens are mounted on a sturdy tripod camera shake can still make it to the final image. How? By the minimal motion caused when pressing the shutter release button. You might think this motion is too small to make a difference, but believe me, it will! And it will invalidate the whole point of using a tripod in the first place. There is a very easy fix for this though:
Instead of manually pressing the shutter release button, set the camera's timer or use a remote control (wired or not) to activate it without touching the camera. These remote controls are available by all camera manufacturers, they are super cheap and very small and a real life saver (well I might be exaggerating a bit here, but you get my point).
Set your camera to "Burst Mode" and your focus to "AI Servo" if you are planning to shoot moving targets and shoot sets of 3 to 5 images each time. This dramatically improves your chances to absolutely "nail" the shot. It also helps "freeze" the action when panning and get your subject in focus with the background blurred in the direction of the motion which is a beautiful effect.
When taking photos of people or animals and are using a shallow Depth of Field (large Aperture), always make sure to focus on the eyes, or at least on the eye closest to you. This trick makes a huge difference in the final image and if the eyes are out of focus, the whole photo will appear to be out of focus as well.
One of the most common mistakes beginner photographers make is neglecting to clean their lenses. This might be because they are too scared to attempt cleaning such expensive gear by themselves, or simply because they are unaware of the impact even a minimal amount of dirt has on image quality.
To put it boldly, dust, dirt and oily fingerprints on a lens surface are the safest guarantee to inaccurate focusing and poor image contrast. So always make sure your front and rear lens elements are spotless and always protect them with high quality protective filters such as those from B+W and Hoya.
I hope you enjoyed my Top 10 Tips on how to take sharper photos with your DSLR. If you have any questions, comments or suggestions please post them in the "Comments" section below and I will be more than glad to assist.