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The 12 Secrets Of "Tack Sharp" Photos (Every Time)
Have you ever found yourself rushing home after a blisteringly good shoot, then uploading your images only to find some of the 'best' ones are fatally lacking sharpness! This is hugely frustrating, and it happens to everyone when they're learning photography.
So, in this article I'm going to run you through 12 key pointers for ensuring that your pictures turn out perfectly sharp, every time. Remember, though, taking images that are tack sharp is not an end in itself. Capturing something that is actually interesting is always the priority! But mastering the technical qualities of a sharp photo can help you do justice to any subject. Let's get started...
1. The shutter speed/focal length reciprocal rule
This is a key tip that we've seen in many other tutorials on PAC. In a nutshell it is that the shutter speed you select should be at least the reciprocal of the focal length, when you are hand holding the camera. This simply means the bottom number for shutter speed should be at least as big as the number for focal length.
In other words, if shooting with an 80mm lens you need to ensure the shutter speed is 1/80th or more. Doing this means that the unavoidable slight movements you make when holding the camera will not register as blur in the image, because the sensor is not exposed for long enough to pick up on it.
N.B: Bear in mind that, when shooting on a crop sensor camera (as most of us do, since pro camera bodies are so expensive), you will need to set shutter speed based on the increase in effective focal length produced by the crop factor.
So, for example, using a 50mm lens with a Nikon DX camera gives a focal length of 75mm (DX sensors have a 1.5x crop factor). As a result you would want to select a shutter speed of 1/75th or faster.
2. How to hold the camera properly
I know this sounds hugely basic, but I often catch myself gripping the camera in an unhelpful way and have to remind myself of a few basic principles. So, here are so tips for holding the camera and shooting to prevent camera shake as far as possible, which is crucial when shutter speeds are on the slow side.
- Lean against a solid object, like tree trunk or wall. Camera shake doesn't just result from your hands, or your arms, but your whole body. If your legs and torso are propped up by something you gibe yourself a really solid base; kind of like turning yourself into a tripod!
- Tuck in your elbows. If your elbows are held outwards it is harder to fully support the weight of the camera. Try to get as compact as possible to reduce all swaying of the arms.
- Use your face as support! That sounds odd, I know. All I mean is that, when looking through the viewfinder, press the camera right up against your face as this both gives you an unobstructed view through the viewfinder and supports the camera.
- Support the lens with your left hand. Cradle the barrel of the lens with your left hand, so that its weight doesn't cause the camera to 'bob' up and down as you shoot.
- Squeeze the shutter release like the trigger of a gun. The analogy of photography with shooting has been popular ever since Cartier-Bresson drew attention to it. It's not just about shooting when your subject/prey arrives, but also the technique of squeezing, rather than jabbing the shutter release button, so the camera isn't jolted.
3. Accurate focusing is easier said than done
Clearly, getting tack sharp photos has a lot to do with accurate focusing. Sometimes, because modern autofocus systems are so good, it can be easy to become slightly lazy. But even when using AF there are some simple things you can do to ensure the best results. So, here are some key focusing pointers:
- Use Continuous tracking (AI Servo for Canon, AF-C for Nikon) to focus just once, and remain locked on to the subject even as it moves around. This is obviously applicable to sports and wildlife shooting, but there are actually a huge range of situations it can be useful for. Any kind of indoor event photography, for example a wedding ceremony, typically entails shooting moving subjects with a wide aperture, for which continuous tracking is really handy.
- Make use of just one of the focus points in the viewfinder, instead of the whole grid. It's really easy to scroll bewtween the different focus points by using the joystick control on the back of Canon and Nikon DSLR's. When all, or a cluster, of focus points are used, there is an element of pot-luck that the camera will pick out the precise area that needs to be sharpest. The central focus point is typically the most accurate.
- Avoid over-reliance on the focus-an-recompose method. This is a perfectly decent system lots of the time. But, especially when shooting with wide apertures, the process of focusing with the central point then recomposing with focus still locked in can prodcue a subtle change in distance from the subject. This is often enough to throw the key area just out of focus (i.e. instead of the eye being in focus, you end up with the glasses rim!).
- Get the hang of manual focusing. There's absolutely no need to focus manually as a general rule, but you'll be glad of a bit of practice in certain conditions, where the AF starts to struggle. For example, when the light is fading or there is a lack of clear edges, you may find the AF searches incessantly for a point of focus, with no luck. That's the time to use the manual focus ring.
4. Ever heard of the 'diopter'?
The diopter is just the little dial that you'll see next to the viewfinder on your camera. It has a '+' and '-' symbol on it and is used for adjusting the clarity of the viewfinder to your eye. It's essential that it is set correctly for you, otherwise you will never know when the focus is actually right!
Set your aperture to its widest setting and focus to something in the far distance. Fiddle about with the diopter until your focus point looks as sharp as it possibly can. That's the setting your diopter should remain on. Be careful not to accidently nudge it out of place, and check to see it's as it should be from time to time.
5. So much depends on good glass
When I first began exploring photography I took all my shots with the 18-70mm f3.5-4.5 kit lens that my camera came with. It was decent enough, but I didn't really know how much sharper images could be until I got hold of a 35mm f1.8 prime lens (which gave me 50mm effective focal length).
The many moving parts within a zoom lens are part of the reason why image sharpness is often less than with a prime lens. So I'd encourage anyone who's thinking about their first lens upgrade to go for a 35mm or 50mm f1.8 prime, because the clarity and sharpness will blow you away.
The more lenses you buy the more you will realise how so much rests upon the quality of the glass you are using. So, although you should be able to get very sharp results with your first kit lens, one of the reasons beginners can often be frustrated by the sharpness of their images compared to others they see is simply the quality of lens is not great.
6. Shooting at the extremes of aperture
One of the great things about a fast lens (with a large maximum aperture) is that it enables more light to enter the camera, which in turn makes faster shutter speeds possible in low light, cutting out blur caused by camera shake. Another great thing is the lovely soft circles that form in the out-of-focus areas (bokeh).
But large apertures can be a double edged sword when it comes to sharpness. With some lenses you will notice that the point of focus is sharpest about 2 stops down from wide open (i.e. about f5.6 for an f2.8 lens).
If you need to shoot wide open to avoid a slow shutter speed, do it, because blur from a slow shutter speed will damage sharpness more. But, if possible, it can be worth pulling back from the maximum aperture to get tack sharp results. It's important to compare the results you get with different apertures on your own lens to get a feel for how necessary this is/isn't.
Shooting at extremely narrow apertures can also have a detrimental effect on sharpness. Narrow apertures produce a large depth of field, placing more of the image in sharp focus. But most lenses have a tipping point, where the aperture becomes so narrow that something called 'diffraction' begins to occur.
Diffraction is where beams of light entering a very small aperture start to bump in to each other and disperse, effectively undermining the benefit of a large depth of field. So for landscape photos, that require a large depth of field, I rarely push the aperture smaller than f13 or f16. Again, it's well worth testing some results with your own kit.
7. Freezing action? Shoot faster than you think
The reciprocal rule holds for most situations, where you do not need to freeze the fast-moving action. But when your subject is moving at high speed the shutter speed needs to be faster than people sometimes imagine.
I often used to come back from sports matches, or from photographing birds in flight, and be disappointed by the lack of sharpness. I'd focused accurately, used an aperture of around f8 to ensure the subject didn't fall out of the depth of field area, held the camera steady etc.
The reason I was not happy with the results was that I assumed if the shutter speed was anywhere north of 1/300th everything would be frozen. That's such a tiny fraction of a second that surely it would freeze all motion, right?
Wrong. It's amazing how much motion can be recorded on the sensor even with an exposure time this short. Now, I always shoot in shutter priority mode for sport and wildlife and try to keep the shutter speed at or above 1/800th. If the aperture has to be wide open, so be it; it just makes careful focusing all the more important.
8. Image stabilization is your friend
Many telephoto lenses feature image stabilization technology. This is called Image Stabiliztion (IS) with Canon cameras and Vibration Reduction (VR) with Nikon cameras. Whenever you are in the market for a long zoom lens, it's really important to find one with this feature.
Hand-holding with a telephoto lens always increases the risk of camera shake, because the high magnification of these lenses also magnifies any slight movement. IS/VR works by anticipating this movement and actually creating a small amount of counter-movement to undermine the camera shake.
So make sure that your IS/VR is only switched on when hand-holding. If you use it with a tripod, the small amount of movement it creates will, in fact, contribute to blur rather than negating it!
9. A solid tripod makes a world of difference
Despite all of the above tips for getting sharp results when hand holding, if the conditions allow it then shooting with a tripod will usually make it far easier to get tack sharp photos.
A tripod also frees you up to think more about the depth of field than shutter speed, provided you do not need to freeze action. When choosing a tripod make sure that you go for one that supports the weight of your camera + heaviest lens.
If the legs begin to quiver, or the head drop, under the bulk of your beefy magnesium alloy DSLR, it's no better than hand holding. But a strong tripod does not mean it has to be heavy to lug around, thanks to carbon fibre which is both very sturdy and lightweight.
10. Cable release - fun and effective
If you can combine a tripod with a cable release, even better. The tripod accounts for any movement caused by the movements of your body. But you still have to press the shutter button with your finger. Surprisingly, this alone can send little vibrations through the camera which are picked up by the sensor.
A cable release is a really simple device that plugs into your camera at one end and has a little button for firing the shutter release at the other. So you can take pictures with your camera on a tripod, and never have to touch the camera.
If you want to shoot in Bulb mode (which involves holding the shutter down for as long as you want the exposure to be) for something like fireworks, you can still do this using the button on a cable release.
If you don't have a cable release to use with your tripod it's a good idea to use the self-timer. This fires the shutter after a specified interval of time, which means you don't have to touch the camera.
The problem with the self-timer is, for some subjects, it leaves you hoping that the crucial thing happens at the right moment (e.g. the firework explodes or the wave breaks on the beach). Meanwhile a cable release gives you all the control you would have if you were pressing the shutter release by hand.
11. Careful post-production sharpening goes a long way
Almost all pictures benefit from a bit of post-processing sharpening. Obviously, if you shoot Raw (which I recommend), then images are processed in the conversion software, which includes colour balance, contrast, sharpening etc.
JPEG photos have a certain amount of sharpening applied to them immediately in the camera. You can specify the level of sharpening this entails within your camera's menus. JPEG's are, by definition, ready processed and just about good to go straight away.
But I still like to apply some sharpening in Photoshop to most of my JPEG's, if I have the chance. Similarly, I like to apply a bit of sharpening to Raw files in Adobe Camera Raw and then fine tune it with the Unsharp Mask filter in the Photoshop workspace.
This is my complete guide to sharpening images in Photoshop.
12. Light: creating the impression of sharpness
Sometimes the impression of sharpness is more important than the actual technical qualities of sharpness. What does that mean? Well, photography is all about capturing light, and the interest/character/angle/strength/contrast/mood of that light all go a long way to determining impact a photo has on the viewer.
Provided you do a good enough job of most of the above 11 technical points, the light is what really matters. For example, when light is directed to the subject from a sideways angle, it often helps to model the shapes, textures and contours of the face (or whatever the subject happens to be be) more effectively.
A photograph with high contrast and no post-production sharpening will often look 'sharper', or at least clearer, than one with low contrast that has been sharpened in post. Bright, angled light that falls over the subject in an interesting way provides satisfying 'pop' and clarity to an image.
So remember that sharpness is not an end in itself, but one aspect of how we can make strong images. The impression of clarity that we hope to achieve by creating tack sharp pictures can also, in part, be effected by good light.
I hope these 12 pointers for creating tack sharp photos have been helpful. It's always worth bearing in mind that the only point of making a photo really sharp is to make it more interesting, or to be more compelling when printed. For some types of shot this is more important, i.e. it's nice to see all the details of a landscape or nature picture, but with a street scene it's much less significant.
Lots of things carry the interest of an image, including: subject, moment, compostion, concept, colour and light. It's good to aim for tack sharp results whenever possible, provided it doesn't become an end in itself.