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Photography Tips

Image Stabilization = Sharper Images

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All camera brands offer some form of image stabilization. The technology is wonderful! Whenever you are using slower shutter speeds while holding the camera, hand vibration will cause some amount of motion blur, making the image less sharp. In these situations, image stabilization can really help. Images that otherwise would turn out a little soft (unsharp) will be much sharper with image stabilization.

Every camera and lens manufacturer calls this technology something different, adding a little confusion. Canon calls it Image Stabilization. Nikon calls it Vibration Reduction. Sony calls it Super Steady Shot. Tamron calls it Vibration Compensation. It’s all basically the same idea.

The different manufacturers implement this feature in different ways. Some have it built into the camera body, and others build it into the lens. Canon and Nikon build it into their lenses. The catch is, not all lenses have this feature. Generally, lenses that have this feature cost a bit more than ones that do not. I personally believe it is worth the extra cost.

Usually the manufacturer will indicate the degree to which their stabilization will help. For example, they may say a lens offers “3 stops of image stabilization.” To know what is meant by that, you have to consider a basic rule about what shutter speed is sufficiently fast to freeze any motion blur introduced by hand movement/vibration.

That rule says the shutter speed should be at least 1 / focal length when using a camera with a “full frame” sensor. So if you are shooting with a 200mm lens, you should ensure the shutter speed is at least 1/200th second or faster. Or if you are not using a camera with a full frame sensor, such as a camera with an APS-C sensor, then you need to take into account the sensor “crop factor” (typically 1.5X on most Nikons and 1.6X on most Canons with APS-C sensors). That means with that same 200mm lens on a Canon Rebel DSLR with a 1.6X crop factor, is effectively producing images that look like they were shot with a 1.6 X 200mm lens (320mm) and you should really shoot at least 1/320th second or faster.

Now, back to that lens that says it offers “3 stops of image stabilization”. If you are shooting with a 200mm lens they mean you can break that shutter speed rule I mentioned above by three stops. A stop is a photography term referring to the doubling of the light. So, in terms of the shutter speed, “one stop” means making the shutter speed twice as slow, like going from 1/200th to 1/100th.

If you are using a 200mm lens on a full frame sensor camera, you should normally try to shoot at 1/200th second or faster. If the lens offers “one stop” of image stabilization, then you can get away with shooting at 1/100th. If it offers three stops of image stabilization, you can theoretically shoot at 1/25th second! (1/200th -> 1/100th -> 1/50th -> 1/25th). Wow!

Just note that it is probably risky to go that far with trusting the image stabilization to sharpen up a slow shutter speed shot, but it sure helps having that feature when you simply must use a slow shutter speed hand-held, like when shooting in a low light scenario. If it turns out the image stabilization just isn’t getting the job done well enough, that means it is time for you to shift to a higher ISO which will enable you to shoot at faster shutter speeds.

One more note about terminology you might encounter:  Sometimes you might see the term “EV” used instead of “stops.” They mean the same thing. “EV” stands for Exposure Value and technically is the more accurate term when talking about varying shutter speeds. A “stop” normally refers to the aperture values, but when we are talking about shifting shutter speeds by an amount that is the equivalent of adjusting the light by one f/stop, that is said to be an adjustment of one EV. Still, you will find many manufacturers talk about the image stabilization in terms of stops instead of EV’s. It’s all the same.

Also, note that lenses that offer image stabilization have an off/on switch, and some offer more than one mode of operation. Check the manual that came with your lens for more information about its features and any limitations. For example, the reason they have an off/on switch is because when you are shooting on a tripod, you should turn off the image stabilization.  Again, check your manual for more information about that.  Just remember to turn the image stabilization back ON when you are shooting hand-held!

This feature is so important; you really need to make sure you know how to use it!  Using this technology will help ensure you get consistently sharper hand-held shots! It’s a “must use” feature!

Image Stabilizer Example

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Photography Tips

Ten Tips for Sharper Images

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One thing I regularly emphasize to my students is the importance of image sharpness. All too often, I see photographers take photos that are a little ‘soft’ and that sometimes kills an otherwise great photo! If you have this problem, here are ten tips that can help you ensure your images come out sharp.

These tips are provided to help you get sharper images with the gear you currently own, but remember lenses are not all equally sharp. So, in some cases, if your images are consistently “soft”, it might mean you need to change lenses. But first, way before you go out and buy anything new, try all the tips below.

Mythbuster Fact:  First of all, I should mention that I sometimes encounter photographers who think the problem is that they need a higher resolution camera, and they rush to get ‘more megapixels’, but actually that is not going to make that much difference. So, save your dollars and put these tips into practice:

1. Make sure you are accurately focusing on the part of the photo you want to be sharp. I know, this sounds obvious, but it’s tempting to let the camera’s autofocus system do all the work and let it choose which ‘focus points’ to use, and it might make a decision to focus on the wrong thing. Make sure you read up on how your camera’s focus points work, and whether they detect vertical or horizontal line contrast, or both. That helps explain why the focus points don’t work as well as expected in some situations. Also, with most cameras, you can tell the camera to only use specific focus points, instead of all focus points. That means you can tell the camera to focus on only one area. If you do that, you can then point the selected focus point precisely at the subject you want to be in sharp focus, and press the button to lock focus on what’s most important. Then you can reframe the shot and take the perfectly focused photo!

Some photographers like to use an option available on many cameras called ‘Back Button Focus’.  That way you can have the focusing be controlled by a separate button in back, instead of it being tied to the shutter release button. With that option, you can point the selected focus point where you want to focus, hit that back button, and then know your camera has been focused at that spot without the need to re-focus on every shot.

2. Keep in mind that you can control depth of field (the range front to back that appears to be sharp) by adjusting your aperture. If you use a wide aperture value like f/2.8, then you’ll have a shallow depth of field and focusing becomes even more critical. For example, if you focus on someone’s nose, their eyes might be slightly out of focus. (And it’s REALLY important to have the eyes in focus!!) You can increase the depth of field by using an aperture value of f/11 or f/16 instead. That will give you greater depth of field, which is especially useful if you are taking a group photo. It’s important to make sure everyone in the group looks sharp, not just the front row! Using Aperture Priority exposure mode (A on Nikon, Av on Canon) is a great way of controlling your aperture value.

Also note that your choice of lens focal length affects depth of field. The longer the focal length, the shallower the depth of field at a particular f/stop. So, focus becomes even more critical as you go to longer focal lengths.

3. Shutter Speed: Sometimes a ‘soft’ image that looks ‘out of focus’ might not really be out of focus at all! The other big culprit is shutter speed. If you hand-hold a shot at a shutter speed that is too low, the photograph will pick up the hand vibration as ‘blur’ that prevent s the image from looking sharp. The slower the shutter, the more likely the image won’t be sharp. There are several ways to deal with this. Read on…

4. Stabilize the Camera: Of course, if motion blur is causing your image to not be sharp, you can put the camera on a tripod. That provides a more stable platform for holding the camera, and thus at slow shutter speeds your image will be sharper. And if you don’t have a tripod, you can always try to brace the camera against a tree, a post, a railing, or a wall (etc.).

5. ‘Image Stabilization’ or ‘Vibration Reduction’ (or any of a wide variety of other terms, based on the brand), can be a huge plus! This technology helps stabilize the image, even if you are hand-holding the camera. This will allow you to use a little shower shutter speed than would otherwise be ‘safe’ to use for hand-held photography. Since photographers often hand-hold their camera for most shots, this is a really valuable feature to have, and is well worth the extra cost.

Ironically with some cameras and lenses, having this feature turned on can actually cause a problem when shooting from a tripod. So, turn it off when using a tripod, and then the hard part is to remember to turn it back on when you start shooting hand-held again.

6. Proper holding of the camera is a factor also! When holding the camera, make sure to hold your elbows close to your body, bracing your arms against you, giving them more stable support. Also make sure you have firm footing and as you fire the shutter, relax and exhale softly and squeeze off the shot. (Yes this really helps!)

7. A General Guideline: I still haven’t explained how slow is ‘too slow’ for a hand-held shutter speed. The old rule has always been 1/focal-length as the minimum safest shutter speed. So for a 200mm lens, shooting below 1/200th of a second means you risk a soft/blurry shot. You have to keep in mind, though, the crop factor of your sensor. If your camera has 1 .5 crop factor, then that lens is effectively a 300mm lens, so the minimum safe shutter speed would be 1/300th. This calculated ‘minimum shutter speed’ is just a guideline and is not precise. Sometimes you can get lucky and shoot at a little slower shutter speed, but it’s just risky. I think it’s best to stay well above that minimum safe shutter speed if you can. Remember, Image Stabilization / Vibration Reduction helps a lot, allowing you to shoot at a little slower shutter speed and still get sharp shots.

Note this guideline about shutter speed is in regard to handheld shots only. When shooting from a tripod, you don’t have to follow this rule.

ALSO, note that there is one other importan consideration regarding shutter speed and image sharpness. If there are portions of the scene that are in motion such as wind blowing trees or flowers or grass, then you will need a faster shutter speed, otherwise they will be blurred. If the main subject is moving, such as a person running, a car moving fast, or a bird taking off, etc. you’ll also need to ensure the shutter speed is fast enough.  So these circumstances might require shutter speeds ranging anywhere from 1/500th to 1/2000th or so.

8. Increase ISO when you need to!  When you are shooting, ALWAYS pay attention to the shutter speed you are using. If it is in a risky range or the images are turning out ‘soft’, fix the problem immediately rather than just ‘hoping they’ll turn out anyway’. Go ahead and move up to a higher ISO setting. That will allow your shutter speed to be faster for the same aperture value. Move the ISO as high as you need to ensure the images are not blurred! Even if it means going to a range where you start adding more ‘noise’ due to the higher ISO value. It’s better to get a sharp grainy shot, rather than a blurred non-grainy shot.

9. Check your work! The good news is that when shooting with a digital camera, you can check your work right then!If you have ANY question about whether the images are turning out sharp, check it on the back of your camera. Zoom in on the image preview and make sure it is sharp, and if not, make corrections immediately before taking any more photos.

10. Digital Sharpening: There are two final considerations for creating sharp images, both related to digital image sharpening. If you’re shooting JPG in camera, then your camera has settings that affect JPG image sharpening done in camera. Check your camera manual about image sharpening and features such as ‘Picture Styles’, ‘Picture Control Styles’, ‘Creative Styles’, or a variety of other names based on camera brand. Also, once the images are on your computer, you can add some image sharpening, depending on what software you use. Some judicious image sharpening can really add that last little bit of sharpness that makes the image look nice and crisp. The exact amount of sharpening you do depends on how the image is to be presented. The sharpening needed for a 16×20 print is different than the sharpening needed for a photo you post on facebook or in creating a slideshow.

These ten tips will ensure you are creating consistently nice sharp photos, freeing you up to think about all the other factors that create a great photograph such as composition, light, color, etc.

Are there other considerations that affect sharpness?  You bet there are! These are just the highlights!  Optical qualities of the lens can make a big difference IF you are following the guidelines above.  If you don’t follow the guidelines above, then you’ll miss out on the benefit of having a higher quality lens.  Also factors like diffraction at higher f/stops, chromatic aberration, are other considerations.  I’ll leave those topics for another day. 🙂

Remember I offer classes to help you take better photos!  Sign up if you haven’t already!

Happy Picture-Taking!

Kevin Gourley

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