Linckinn wrote:
I have recently been taking hand held eagle, wood stork, and egret pictures with medium telephoto (Nikon 55-300 and Panasonic 100-300) lenses. In most cases there is a little softness, not enough to totally ruin the picture, but not the sharpness I would like. I have experimented to try to determine if the problem is focus, camera shake, or inferior lens. Depending on the answer, the solution could be new camera, new lens, or always use tripod. I would hate to lay out the money only to find I have diagnosed incorrectly and there is no improvement.
I have concluded that the problem is camera shake (I have reasonably steady hands, but am 72, so not perfect). With cameras like the new Olympus advertising 5.5 "stops" of IS, it occurred to me why not just move the ISO 3 or 4 stops in my existing cameras and gain the resulting shutter speed. If my camera and lens IS is 2 or 3, maybe that would accomplish the same thing. There is no appreciable noise at 800 or even 1600, especially in sun light. I tried it and got much improved results. (I was already shooting at 1/effective focal length or more, so the above was at numbers like 1/3000.)
So my question is what am I missing? The above seems way too simple. Is there a direct correlation with shutter speed and image stabilization, or is something else going on? Any thoughts would be much appreciated.
So, what am I missing?
I have recently been taking hand held eagle, wood ... (
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There are a number of things you can try, to maximize the sharpness of your images...
1. If you have a "protection" filter on the lens, remove it and try without any filter. There are various qualities of filters and some lenses simply don't work well with filters (the original Canon 100-400mm "push/pull" zoom is one I know of, for certain).
2. Use a lens hood. It can improve contrast in images, which in turn helps with apparent sharpness.
3. Keep your shutter speed "high enough"... without any stabilization the rule of thumb for full frame/35mm film cameras is that the shutter speed should be the reciprocal of the lens focal length. So for 300mm a shutter speed of 1/300 or faster would be ideal. But with smaller format digital sensors faster might be required.... The same 300mm lens on a Nikon DX camera calls for a minimum shutter speed of 1/450, for example (1.5X). On a Micro Four/Thirds sensor camera, the same 300mm lens would call for a minimum 1/600 shutter speed (2X). But this is only an estimate. Someone with really good hand-holding skills might be able to use a little slower shutter speed, while someone else may need a little faster. A tripod or monopod might allow using a slower shutter speed than can be hand-held.... but if a subject is moving you might need to keep shutter speeds up there anyway, to
4. Use the lowest possible ISO that will allow you to use a "fast enough" shutter speed at the aperture you want to use. Higher ISOs have greater risk of noise in digital images, as well as less dynamic range and somewhat reduced resolution. There's also loss of fine detail and apparent sharpness to noise reduction, which needs to be applied more strongly at higher ISOs.
5. Stop down your lens. Most lenses are not at their sharpest wide open.... will perform better and render a sharper image a stop or two down from wide open.
6. A big part of your job as the photographer is to balance #3, #4 and #5 against each other to get the best possible combo in any particular situation.
7. Get closer to your subject. Fill your viewfinder and try to do as little cropping as possible. Cropping heavily leaves magnifies any flaws, while dramatically reducing the number of pixels that make up the image.
8. Lack of sharpness also can be due to focus error. Inspect your images to see if something closer or farther away than the subject appears sharper. If so, it could be your focusing technique is off or that the focus system need adjustment. That might be possible for you to do yourself, many cameras and some lenses today have some means for the user to fine tune focus accuracy. Other systems can only be adjusted for focus accuracy by a repair tech. Stopping down the lens as described in #5 also may help hide minor focus error, too.
9. Clean your camera's sensor. Often dirt on a sensor won't show in images... particularly when using longer telephoto lenses and larger apertures. But with a dirty sensor there can be significant loss of resolution and fine detail due to that stuff on the sensor.
10. Get a better lens. The sharpest telephotos use fluorite or elements that try to emulate fluorite. For many years, Canon has used fluorite extensively in their telephotos. There are actually only a few Canon lenses 200mm or longer that
don't incorporate fluorite. Nikon has recently reworked most of their telephotos to use fluorite, too. AFAIK, no other manufacturer is using fluorite right now, though Sigma uses some "FLD" elements they claim have the same properties. Lens autofocus performance also can be a big factor, if your "soft" images are actually due to missed focus and not camera shake.
Zooms have improved immensely over the last 20 or 25 years, some of the best ones now rival high-end prime lenses for sharpness and other image qualities. But the best zooms have moderate ranges... 2X, 3X, 4X and maybe 5X, 6X at most. One of your lenses is a little less than 6X and the other is 3X, so they may be reasonably good in this respect. It's a mistake, though, to think a zoom that tries to cover too wide a range will have similar performance. There are a lot of 10X, even 15X and 20X zooms being sold these days. They may be convenient, but very likely compromise in a lot of other ways.
Oh, and 300mm on a Nikon DX camera is not a "medium telephoto"... It's a quite powerful lens that's got a lot of "reach" (and, AFAIK, all 55-300mm are DX lenses... so I assume you're using a DX camera). I don't know what you are using the Panasonic lens upon, but it's a Four/Thirds format camera then 300mm on that is 33% more powerful than 300mm on the Nikon camera. This makes getting a steady shot even harder.
Post-processing can play a big roll, too. Most images need some sharpening, which is usually best done as one of the last steps in post. Also, most computer monitors don't have all that good resolution or sharpness. An image might be better than you think. Another mistake people commonly make in post-processing is being overly critical of their images... by looking at them too magnified. An image from a 20MP camera displayed at "100%" on a computer monitor is like making a 3 foot by 5 foot print and then viewing it from only 18 or 20" away. That's ridiculous, but it's what a lot of people do! While it's fine to zoom in to high levels of magnification when doing some retouching, it just makes sense to back off to a more reasonable size... more like how you'll actually be using the image... to evaluate things like sharpness and focus accuracy. Even then, a print done on smooth, matte paper with a high quality printer will usually be sharper than what's seen on most computer screens!
Yes, image stabilization can help you get a steady shot. Canon pioneered image stabilization with their SLR system in the 1990s... That attracted a lot of buyers! To remain competitive, everyone else has since followed suit and implemented their own forms of stabilization. There are two primary types, both of which work pretty well. You mention Olympus who use in-camera (sometimes called IBIS or "in-body-image-stabilization"), moving the image sensor around to correct for movements. Pentax and many Sony use similar. Canon and Nikon use in-lens image stabilization, moving a group of optical elements inside the lens to correct for movement. Sony is mostly IBIS, but has a few lenses with it, too.
One difference, in-lens stabilization also steadies what's seen in an optical viewfinder... which can be helpful when trying to keep a long telephoto lens on a moving subject, much like stabilized binoculars. This isn't the case with IBIS, unless the camera uses an electronic viewfinder. (Recent EVF are better, but in the past they have not been particularly good working with active subjects such as sports and wildlife. Many folks still prefer an optical VF with these types of subjects.)
There's lots of hype about "5-Axis" IS and such, that may or may not mean all that much. Two-axis is up/down, right/left. If you think about it, continuous autofocus actually acts like another axis, front/back. Rotational and tilt are the other two claimed. By combining corrections done with up/down, right/left and front/back, those are actually being addressed as well.
There are also a lot of claims about effectiveness. "Up to three or four stops" of assistance, for example, just means that you can expect a high percentage of successful shots at three or four stops slower shutter speed than you'd usually need for handheld shooting... It still depends upon one's skill hand holding a steady shot and there's bound to be some variation from person to person. Maybe you can get most shots sharp holding a particular lens at 1/200, but I'm not as steady or careful and need 1/300 to assure a reasonably high number of acceptably sharp shots. In that case the three to four stops worth of assistance for you means 1/25 or possibly even 1/12, but for me it's 1/40 or 1/20. Some of the best lens and camera reviewers put the gear through a series of test shots and report how accurate the manufacturers' claims are, as far as their concerned.
Personally I've been using image stabilized lenses for about fifteen years and probably shot about a half million images with them. In fact, IS was one of the main reasons I switched to the Canon system in 2001. I love it, especially on longer lenses... Though it's nice to have on any lens, a lot of wide angles and normal or short telephoto lenses still don't have it, but they are relatively easily handheld. I shoot mostly sports (probably 80-90%) and anyone who tells you that it's not needed for sports/action shooting is simply justifying their own decision to buy a cheaper lens without it. While it may not be essential when using faster shutter speeds to freeze subject motion, it can't hurt and can make possible shots that would otherwise be impossible. It makes handheld shooting a lot more practical, allowing me to be more mobile. And, as mentioned, stabilization also can steady the image seen in an optical viewfinder, helping me stay on target when tracking moving subjects.
One possible drawback, a lot of Nikon shooters think VR slows autofocus a wee bit and there seems to be some evidence to support that. I feel it's the opposite with Canon IS, that it helps autofocus work faster and better. But it's not like I've got any means of testing this... It's just based on experience with the lenses.
Hope this helps!