repeated streaking using a tripod and remote shutter release.

mrsnoogle · Jul 16, 2007

hey there....
I have just recently purchased my first dslr, a pentax k100d and am having some troubles getting the sharpness I expected. I am using a sigma 70-300mm dg apo zoom lens in macro mode on a tripod with a remote shutter release and a 2 second delay (flicking up the mirror before the picture is taken) but am still getting streaking.

Shot with PENTAX K100D at 2007-07-16

The shots were taken repeatedly in an inside environment without any wind of any kind using a flash and each time an almost identical blur/streak in the same direction was captured. The other settings are (1/180, f5.6, 0.0 ev, iso 200).

Does anybody know how i could possibly be going wrong here?

any help is of course much appreciated...
camm.

Iron Flatline · Jul 16, 2007

Wow, got me stumped, but I look forward to hearing the answer. Does your camera have one of those sensors that shakes dirt off?

Johnboy2978 · Jul 16, 2007

Is the 100D equipped w/ image stabilization? I have the k10d and the manual says that if you have it mounted on a tripod to turn off image stabilization. Try that in addition to the settings you mentioned above and repeat. I haven't had issues w/ mine with it on or off when shooting on a tripod though.

Garbz · Jul 16, 2007

Shake Reduction.

It's a fantastic feature, unless there is no shaking. It's a common problem in Nikon's VR Canon's IS, and probably every other company's version of the technology. When a camera is mounted on a tripod there is negligible shake, even less so when mirror lockup is used. The sensor may still be trying to compensate with the exception that there's nothing to compensate for and it actually causes a camera shake type picture like the one above.

Try turning shake reduction off and seeing if it still works. If it is off... I'm out of ideas.

/EDIT: Damn tabbed browsing people are replying while I'm reading other posts >_<

mrsnoogle · Jul 16, 2007

shake reduction turned off.

results are the same

... could this be a problem with the camera? or maybe the lens?

mrsnoogle · Jul 16, 2007

a few more. all shot on a tripod, all showing the same streaking problem

Shot with PENTAX K100D at 2007-07-16

jwkwd · Jul 16, 2007

Have you tried manual focus?

tempra · Jul 16, 2007

Have you tried a different lens? does it do it with that, could be the lens is dodgy, or failing that, the camera

mrsnoogle · Jul 16, 2007

images are razor sharp with the 18-55 kit lens. The streaking happpens at the 200-300mm range reagrless of what i do, shake reduction on or off, tripod or laying it on a table, locking mirror or not.

Is this kind of thing known to happen in dodgy lenses?

tempra · Jul 16, 2007

I dunno, but if they are sharp at shorter focal lengths, it really seems like the lens is duff as the camera takes the same pic regardless of focal length.

Can you take it back and get an exchange, or at least try it on another camera to see if the same results occur

Mike_E · Jul 16, 2007

Try going to a camera shop and trying another lens of that type. If it still has issues then look to your camera, and if not then you need a new lens.

mike

Big Mike · Jul 16, 2007

It's certainly not unheard of that a lens may be misaligned or malfunctioning. They are, after all...precision optics and need to be within very tight tolerances in order for them to work properly. Same for the camera as well.

The easy check would be to try the lens on a different camera.

You may need to exchange it or send it in for repair.

sabbath999 · Jul 16, 2007

Does the image look clear when you are shooting through the viewfinder?

Also, something else to try. Crank your ISO ALL the way up... however high it will go. Enter Shutter priority mode or program mode, and crank your shutter speed up to as high as you can and still get a properly exposed image. Then, go outside and shoot some stuff. Don't worry about image composition, or noise, or anything else... we are not trying to produce art here, just some test images.

If the images are clear, then the lens is in alignment and the mounts are OK, and we have to keep looking. If the images are still blurry, then there is a lens problem.

If your images are sharp, take your camera off the tripod and put it on a bean bag. It could be the lens mount, the camera mount, the tripod head, or the tripod its self.

If your camera is tack sharp on the kit lens, then your camera is likely OK... assuming the lens mount is not loose.

doenoe · Jul 16, 2007

what kind of tripod are you using? Cause with a 300mm on it, you need a good tripod. Not one of those table thingies.

Garbz · Jul 16, 2007

Ok one more thing you can try is using the self timer. If your tripod is anything like mine it won't steady well with a 300mm lens and a slow shutter speed when I manually push the button.

If you can rule out shake, and shake reduction is off, and another lens works, then the lens in question must be faulty.