Blurry Photos

whardman · May 28, 2006

I have a Sigma Zoom 100-300mm f4.5 6.7 lens and have noticed that the photos seem fuzzy / blurry. I notice it mostly at 300mm as that is the zoom that I usually use it at. It is not camera motion as it happens even on a tripod at 1/1200. I was wondering why it is fuzzy, is it quality of the lens? Is there anything I could do to fix this problem?

Torus34 · May 28, 2006

Manual focus?

whardman · May 28, 2006

It's auto focus.

Here is an example of what I'm talking about. It was taken at 1/1600 at F6.7.

PopPicker · May 28, 2006

I think my money would still be on camera shake or perhaps lens shake.

Although you have the camera on tripod you are obviously moving the camera to keep up with the plane. So one would assume that the camera is moving somewhat at the moment you pressed the button.

Is this a crop of the original image or the full thing?

A better test would be to set it on a tripod and take a photo of a static object at a simliar distance. Trying both auto focus mode and manual as some auto focus lenses are quite loose, I would think though that your shot the lens would have been on infinity anyway, so manual focusing would be easy.

Let us know how you fair.

PP

Philip Weir · May 28, 2006

It looks to me like movement. Notice the blurring in front of the wings and wheel, especially the rear wings. If you are on a tripod or not, you will need to pan as you are shooting. A simple test is to shoot a still object at roughly the same distance on a tripod. Philip.
www.philipweirphotography.com

whardman · May 28, 2006

This prtucular photo was taken by hand but I tried taking pitures of still objects and I get very similar results even on a tripod with the same speed and aperture. That is why I don't think it is camera shake ... but I could be wrong. I'll post a picture of a still object in the morning when the sun is out.

This is a crop of the original photo as the original was to large to post and the blurriness dissappears if the image is shrunk.

PopPicker · May 28, 2006

Yep Philip, I zoomed right in and noticed that too.

I was asking about the cropping to see if you were that close to the subject. If you were you did pretty well getting the plane full frame. As it'sa crop you are increasing the problem. But I'm sure we'll work out the issue for you.

PP

whardman · May 29, 2006

I wish I was that close to the aircraft. If I was I wouldn't be as worried about the quality of the image.

This photo is focused at the vent slightly behind the peak of the house. I noticed that the focus appears to be the peak.

This photo seems to have the same focus even though it is focused on the peak.

Both of these photos were taken at 1/250 @ F6.7 ISO 200 on a tripod using a IR remote.

I noticed some of the blurriness in both photos but not as bad as it is sometimes. I'm wondering if maybe the autofocus is off slightly causing the problem.

Jeff Canes · May 29, 2006

Are you’re shooting the planes at infinity if so why not turn the auto focus

Soocom1 · May 29, 2006

My own personal opinion is a focusing plain problem. What I mean by that, is that the lens could be sitting too far forward to focus in on the subject. It could be a loose base, loose elements, etc.

Two items to check for:

One, look at the lens and lens mounting area. See if there is any dirt, or loose screws.
Two, look at the film advance ara, or the sensor if digital. Look for any loose areas, items, screws etc.

The only time I really ran into this was when I had a lens that had a loose front element. After tightening it, presto... It got fixed.

benhasajeep · May 29, 2006

Go over this link. It is for checking focus on your camera. Follow the links and they will let you print out the cards. Set the cards up and do the focus test. This will let you know if its the lens or camera. Also make sure that you do have the correct focus point on your camera chosen. Sometimes it gets changed and you don't realize it.

http://www.photo.net/learn/focustest/

whardman · May 29, 2006

The camera is a Nikon D50. I have another lens Nikkor 18-55mm that focuses perfectly fine, so I don't think there is an issue with the camera.

Oddly I tightened the screws at the base of the lens and it does seem to have helped some (even though they were tight already), but the focus does accasionally seem to be slightly off.

benhasajeep · May 29, 2006

Try switching eyepoints on the camera and see if you have the same results with the sigma. Is the Sigma a new lens or one you had from before / used?

whardman · May 29, 2006

The lens is about 3 year old. I used it with a film camera before, and was using it with the D50 so I wouldn't have to buy new a new lens. Even swtiching eyepoints still yields nearly the same focus, but no better.

benhasajeep · May 29, 2006

What gets me is the roof shots. Although you said if focused on the peak and not the vent. It is a sharp pic.

Are you using a set ISO or auto? I just realized that top pic is noise. For that aperature and shutter speed. The iso must be pretty high. It is out of focus too, but the noise will make it look much worse.