Tuesday, 21 August 2012

How To Take Sharp Pictures

The single most important element in any photography is the sharpness of the picture. It is what differentiates the Professionals from the Amateurs. Every one with a digital camera wants their images to be Tack Sharp, but quite often they are not. (Tack Sharp is a term used in pro circles to describe the ultimate in image sharpness) Let us see how the pros manage to get it done every time let us analyse what do they do different and try to replicate their success.

Photo By Danny Perez

Sharpness of Digital Images is often the result of a number of elements rather than one single thing. Each and every element contributes in its own way to the final result. So to get Tack Sharp Images; “Do Everything Right”.

Let us fist examine the factors that lead to loss of sharpness so that we could have a better understanding of them and know how to deal with them.

The major factors that deteriorates image sharpness are

  •     Incorrect Focus
  •     Inadequate Depth of Field
  •     Camera Shake
  •     Subject Movement and
  •     Image Noise

sharp image
Photo By Johnfish

The first and foremost reason for blurred images is poor or incorrect focus. Then comes the use of wide open apertures so that very little of the subject is in focus. Shake, induced either by camera movement or by subject movement is one other major reason. And finally there is Image Noise resulting from the use of high ISO values.

How to take Tack Sharp Photos with a Digital Camera

  1.     Use a Sturdy Tripod
  2.     Use a Good Tripod Head
  3.     Use a Cable / Remote Shutter Release or Use Self Timer on Camera
  4.     Enable Mirror Lock Up
  5.     Get your Focus Right
  6.     Turn Off Image Stabilization
  7.     Shoot with Your Lens’s Sweet Spot
  8.     Get Professional Quality Lens
  9.     Clean you lens
  10.     Shoot at the Lowest ISO setting
  11.     Zoom in and Check image at 100%

sharp digital photo
Photo By Johnfish

Use a professional quality tripod and head. This point could not be stressed more as it is the most important element in getting sharp photos. Always buy good professional quality tripod and head, even though it might be a bit expensive and also at first you will feel that it is tiring to lug it around everywhere, believe me it’s worth; both the expense and the effort. Although there are very cheap tripods and heads available they will not keep your camera as steady as the professional ones and they are also not so durable and not very user friendly – that’s why they come cheap. Using a tripod allows you a lot of flexibility with the shutter speeds you could work with. Not only have you taken the camera shake out of the equation but also the limits to shutter speeds imposed by hand holding.

Using a tripod was a step in the right direction towards eliminating camera shake but that’s not all. The very act of pressing your camera’s shutter will induce shake. And no matter how hard or soft you press the trigger the shake it generates is always there. Use a cable release or a remote release to trigger your camera’s shutter. If you do not have either of these, use your camera’s timer function to trigger.

sharp digital image
Photo By Johnfish

OK now we have almost brought our camera shake issue under control. I said almost because there is still one element that could cause camera shake even when your camera is sitting perfectly still on a rock solid tripod. It is the mirror located in front of your DSLR camera sensor (Helps you see through the view finder). Let’s review the picture taking process in a DSLR
  •     Shutter button is pressed
  •     Mirror Flips Up
  •     Shutter Curtains Finish their travel
  •     Mirror Flips Down

The very act of the mirror flipping up will cause minute shake and since it is located so close to the sensor it has to be dealt very seriously. Use the mirror lock up function to counter this issue. Mirror lock up when enabled locks up the mirror when you first press the shutter and only takes the picture with a second press of the shutter button. It is estimated that once the mirror flips up it takes 1/30th of a second for the vibrations caused by it to die down. So press once, lock up the mirror, wait a second and press again to take your shot.

sharp image
Photo By Danny Perez

Next comes the issue of Image Stabilization. Image stabilization is a very useful feature, often a life saver when shooting hand held in low light situations. But when you have set up your digital camera on a solid tripod, you have completely eliminated camera shake. You camera does not know this, it assumes that there is always some amount of shake and tries to compensate for something that is not there and thereby induces it own in the process. So when you have set up your camera on a tripod make it a point to turn off your image stabilization.

Subject Movement is one thing where in certain circumstances we have control over and in certain circumstances we have no control of. So if you are in a situation where you could eliminate subject movement completely, do it. Else you should try to use fast enough shutter speeds to freeze the action and get a sharp picture.

Lens quality is directly proportional to image quality and if you need tack sharp images do invest in better quality optics. There is no alternative to it. Also make sure that your lenses are clean from dirt, dust, smudges, finger prints etc. Having a clean lens is as important as having a good quality lens.

Use your lens sweet spot. Every lens has a particular aperture value in which it is the sharpest. Do experiment by taking images at different apertures with your lens and you will see it for real (generally a couple of stops from wide open aperture). This is called the sweet spot of the lens; this is where it is at its best. Now that you know it…..well….

sharp photo
Photo By Danny Perez

Get your focus right, if your focus is off, meaning it is not where it should have been the picture could be completely useless. So always zoom in before taking the shot and make sure that your focus is right where you want it to be. Also once a picture is taken do examine it at 100% on your camera’s LCD and check for sharpness.

Always use the lowest possible ISO to avoid image noise. Since you are already using a tripod you could use any shutter speed you want to get your shot. So try to get the picture with the lowest ISO setting.

How to get Sharp Pictures while Shooting Hand held

  1.     Hold your Camera Properly
  2.     Use the Right Shutter Release Technique
  3.     Turn on Image Stabilization
  4.     Use the Continuous Shooting Mode
  5.     Use a fast Shutter Speed – The Hand holding Rule

sharp picture
Photo By Bill Gracey

This might sound funny but yes there is a correct method for holding your camera, do refer this previous article (How to hold a digital camera) and also a correct way to release the shutter (Shutter Release Technique).

If your camera or lens has the Image Stabilization feature (Vibration Reduction (VR) for Nikon) enable it. Depending on the kind of IS or VR your camera or lens has it will save you at least a couple of stops over the general rule of hand holding (always use a shutter speed greater than your focal length 100mm lens = 1/125 minimum shutter speed). Also use the continuous shooting mode of your camera and shoot in bursts, this way the chances of getting a sharp picture is greatly increased.