28-135 Lens IS issues

<p>Hi guys,<br>

I have a 20d with the 28-135 lS lens. Most of my pictures when enlarged look to be shaky, though I have IS

swtich on the camera set to "I" rather than "O" ( I stands for on and O stands for off is what my thought is ) so

correct me if I am doing something wrong here and also could you please share your thoughts of how would you

avoid this blurry or shaky photos when you are dealing the camera in your hands.</p>

<p>thanks<br>

ravi</p>

 

<p>Pictures with EXIF data? Otherwise it isimpossible to tell.</p>

<p>There is a limit to what IS can do, especially in an older IS design like the one in your lens. Have a look at the exif data of your pictures and/or post an example.</p>

<p>Jos is right..but what about those with telephoto lens at full extension..will that be worse?</p>

<p>Some of them come out nice when I use a tripod but handheld suck...regardless of the zoom.</p>

<p>Quote: "Some of them come out nice when I use a tripod but handheld suck...regardless of the zoom"<br>

There you have your answer. You need to do some reading to understand ISO, Shutter Speed and Aperture Value. Your shots are most likely blurred because the shutter speed was too slow to capture a crisp image. What mode are you using your camera in? Switch to the "fully automatic" mode (the Green square) for now and try again. That way the camera will do all the thinking for you - normally nota good thing, but it should confirm that the issues you are having are user related. </p>

<p>Ravi: what shutter speed(s) and focal-length(s) are you trying to hand-hold?</p>

<p>Yes, give us some examples with the EXIF data intact and someone will probably be able to help you. I think Juergen probably has a point. Even IS cannot totally compensate for really slow speeds and a jittery hand.</p>

<p>ISO 200 Aperture 5.6 Shutter 1/4 Focal length 90mm Flash ON... one of the examples. I am using manual mode to take these pictures.</p>

<p>shutter 1/4sec - that's the problem. You need to be at min of 1/focal length - in your case 1/90th sec. Seriously, put your camera in fully automatic mode and your pics will improve, then learn about exposure, etc.</p>

<p>Way to slow of a shutter speed to have a sharp image. That is really, really pushing it for someone to handhold with IS in my opinion. Raise you ISO speed to get a faster shutter. or use a tripod. If the subject is in motion, raise ISO speed and open up aperture. If you still cannot get closer to 1/200 shutter, consider flash photography.<br>

I see you were using flash.....why the slow shutter speed then?<br>

Derrick</p>

<p>With my old 28-135 I could get some non-shaky shots at 1/4, but usually not. This is pretty much the limit I reached with IS, good brace, proper breathing, and a lot of practice and experience. You just can't count on it.</p>

 

<p>Yes, shutter speed waaaaayyyyy toooooo sssslllloooooowwww. Also don't forget to give the IS time to kick in, a half second or so after half pressing the shutter buttom. All this is covered in your camera instruction book and leaflet for the lens.</p>

<p>90mm = min shutter speed of 1/(90*1,6)=1/144 sec<br>

IS is max 3 stops for this lens (own experience) = 1/18sec</p>

<p>1/4 is about 2 stops more...that's too much. At 4 stops slower (with IS) I have a 10-20% OK rate...never tried 5 stops.</p>

<p>Kasper has nailed it. My own experience with this lens is that I can reguarly handhold at it 1/8th of a second at the 28mm zoom setting if I'm careful. This is consistent with a two stop advantage because of the IS. It does take about a second to let the IS "spool up." IS is very useful, but it is not magic. Of course, it does not help reduce motion blur of the subject. <br>

To solve your problem in your posted example, you could have used ISO 800 which would allow you to shoot at 1/16 shutter speed. With proper holding techniques with IS, you should get sharper images.</p>

<p> </p>

<p>If you have to shoot that slowly, you *can* get a sharp shot, but you've got to use your very best form (stability, proper beathing, quiet nerves, etc.) AND take many more shots, probably on "continuous" mode. The reason is that a sharp image will come down to "luck" at a certain point. What can you do with good luck and good form? I took this photo long, long, long ago with a p&s in a very dim airport lobby. Equivalent focal length was probably about 50mm. I had no image stabilization, and shutter speed was around 1/2 sec. After about 20 shots, I nailed the image. It's as tack sharp as tack sharp can be.<br>

<img src="http://www.graphic-fusion.com/phsleepingchildthumb.jpg" alt="Sleeping Child" width="311" height="249" /></p>

<p>On top of everything else already mentioned, the IS on your 28-135 is, I think, not the latest version. The older versions often offer only about 2 f/stops worth of additional stabilization, and as time passed in the introduction of this technology, the latest versions claim 4+ stops. Without really making an extreme effort, even with IS, you have to be lucky when you are shooting as slow as 1/4.</p>

<p>It's very hard to hold the camera steady enough slower than 1/60. I try to always carry a tripod.</p>