One of the hardest obstacles to overcome as a photographer is learning how to get sharp photos with a shallow depth of field. It is not easy. On film sets, there’s a dedicated person who’s job (among others) is keeping everything in focus. In this article, I’m going to give you a few tips on how to take sharp photos.
Know Your Factors that Affect Shallow Depth OF Field
Novices to experienced photographers may be surprised to know that there are many different factors that influence your overall image sharpness. Here is a brief summary of each area that can potentially affect your image clarity.
I. Shutter speed
Shutter speed is probably the first thing most of us think about when shooting tack-sharp images. Our first lessons in SLR photography are how camera shake and movement can ruin a picture if your shutter speed is too low. For more information on shutter speed and what your minimum shutter speed should be, check out our article Shutter Speed Guideline – The Reciprocal Rule.
The second thing that may come to your mind is your ISO setting. While ISO speeds up the process in which your film/sensor absorbs light, it also adds grain to your image. This grain destroys detail/sharpness in the image. The higher your ISO setting, the more detail is destroyed. New professional DSLR cameras such as the Nikon D700 and the Canon 5d Mark II (and higher models) can shoot at much higher ISO settings while retaining much of the image detail. However, with the proper lighting, it is usually best practice to shoot at the lowest ISO setting possible.
III. Lens quality
The quality of the “glass” (lens) contributes to image sharpness, contrast and saturation. For the most part, professional series Nikon and Canon lenses produce sharper images than cheaper lens models or third party lens manufacturers. However, this generalization does not apply to all lenses, and some tests for select lenses have claimed better overall sharpness from third party manufacturers than their Nikon or Canon counterparts. Does this mean you should buy third party glass? Usage and budget are important factors; but keep in mind that cheap glass, in general, will already put you at a disadvantage when trying to create tack-sharp images.
IV. Image area
In composing your shots, keep in mind that different areas of the image will be softer (less sharp) than others. The center of your frame will always be your sharpest point, while the image will only get softer as you continue to the edge of the frame. While shooting your subject off-center for composition purposes is often necessary, it isn’t in your best interest to compose shots carelessly because you are relying on cropping the image down in post production. In general, areas away from the center will be less sharp relative to the center at wider apertures (F1.4, F2.8, etc), while areas away from the center will have similar sharpness as the center at smaller apertures (F8, F11, etc).
V. Aperture setting
Aperture is probably the last thing you would think of when it comes to obtaining tack-sharp images. However, it is one of the largest determining factors of shooting tack-sharp images. We all know that aperture controls your depth of field. However, did you know that shooting the exact same shot with the exact same focal point will yield different levels of sharpness on your focal point at different apertures? For example, if I focus on the nose of a face at F1.4 and with the exact same exposure value and composition, shoot the same face at F4.0, the nose will actually be sharper in the image shot at F4.0. This is simply because each lens has a “sweet spot.”
Shooting at your lenses sweet spot will improve sharpness, contrast and saturation. Now you may be thinking, “well how do I find the sweet spot on my lens?” There are several rules of thumb, but the most prevalent is that your sweet spot is around 2 full stops above your lens’ minimum (widest) aperture. Depending on the lens, this will be in the range of F4-F11 or so. Keep in mind though, raising your aperture too high (small) will result in aperture diffraction, another phenomenon that will reduce overall clarity.
Focus recompose, The Enemy Of Shallow Depth OF Field
When working with a shallow depth of field, you may have a very small amount actually in focus. Depending on the focal length of your lens, distance to your subject, and the aperture you have chosen, you may have anything from a few inches to a couple of millimeters in focus.
Focus recompose is a technique made popular by cameras that possess some focus points that, putting it kindly, are best avoided (think Canon 5D Mark II). When using cameras like that, photographers often stick to using the center focus point (normally the best) and then recomposing the frame once they have gained focus. The key point here is that by doing so, they have to move the camera. If your depth of field is only as wide as an eyelash, then you could very easily shift that focus with your movement.
Instead, try to select the focus point as near as possible to the point in your scene that you are focusing on, thereby reducing or removing altogether the possibility of losing your focus as you recompose your shot.
This method would be ideal, but as I have already mentioned, on some cameras only the center focus point is worthwhile using. In those cases, your only option is to use the focus-recompose technique. It then becomes critical that you are acutely aware of your movement and that you regularly check the focus on important shots.
Movement Of Any Kind, Yet Another Enemy of Shallow Depth OF Field
It seems that shallow depth of field has a lot of enemies! That’s no surprise when you’re working with what could potentially be as little as millimeters in focus. Following on from the last tip (focus recompose), we have to think about all movement. If the camera moves a millimeter or two, we’re off. If our subject sways back and forth by a millimeter or two, we’re off. You must contemplate the movement of everything in your scene and use that knowledge to make better decisions.
Communication, The Friend Of Shallow Depth Of Field
I gave shallow depth of field so many enemies that I had to think of one friend. Communication. I’ve spoken about direction before in previous articles, like this one here, and this is a critical part of it. Don’t keep what you’re doing a secret. Talk to your subjects whenever you can and explain what you’re doing/trying to achieve. That way they can assist you. If they want good photos, which most clients do, they will be willing to assist you a little.
Unfortunately, some subjects (children and animals, for example) are not the most cooperative. In situations where I cannot communicate with my subject, there are a couple of techniques I use. First, you have to decide if a shallow depth of field will be appropriate. There’s no point if you know every photo will be out. Second, only use a shallow depth of field when you have the upper hand. Using children and animals as an example (they are so closely related anyway), wait until they are stationary, or in the case of children create that scenario (a sitting down family photo, for instance). Another surefire method is to over shoot. Just like I described for the extreme close up of the two little girls, stick your camera on high-speed continuous and fire away.
Bonus – How to Take Sharp Photos Without a Tripod
Tripods are essential tools for images that require slower shutter speeds like images in low-light or images capturing motion blur. But what do when you don’t have your tripod handy? In 60 seconds we’re going to show you how you can get tack sharp images without a tripod.
- Find a place to rest your camera – Is there a place you can rest your camera and still get the desired shot? Use it! Compose your image and utilize your camera’s two-second feature. This will allow you to maintain focus and fire without touching the camera.
- Use a standard grip – Must handhold? Use the standard grip by bringing the left hand underneath the lens to cradle and the right hand to operate the camera, while tucking in the elbows. The biggest perk is being able to shoot steady images at 1/10th of a second.
- Create A human tripod – Need to drag the shutter even further? Take a seat, elevate both legs and lean into your subject with your elbows. This stability technique, along with regulated breathing, can help you get tack sharp images at under a second or more.
We’re always aiming for an image that is as sharp as possible, but is it the end of the world if we’re a little off? The answer to this question will depend on what you are shooting. With product photography, yes it matters. Whereas, a portrait of a couple, family photo, and many other instances are a little less crucial. If you are already working with a very shallow depth of field, then your images will have a very soft quality to them anyhow. In my opinion (and some of you may disagree), we can extend our range of what we call “acceptably in focus.” In terms of what is acceptable, you must use your own judgement. But don’t simply discard an image if the focus is a little off.