Focusing problems, too soft.

DRT-Maverick

My camera seems to have a bad focus, it doesn't focus sharply, so the images are always over soft and slightly blurred. What should I do?

DanielB

DRT-Maverick wrote:

My camera seems to have a bad focus, it doesn't focus sharply, so the images are always over soft and slightly blurred. What should I do?

take 2 sample images...take one with autofocus, then switch it to manual and take one. use a tripod and a cable release. then come back here with the images and we'll go from there

DavidTO

Post one of your problem images and the EXIF, that'll be a good start.

DRT-Maverick

DanielB wrote:

take 2 sample images...take one with autofocus, then switch it to manual and take one. use a tripod and a cable release. then come back here with the images and we'll go from there

I know how to set my eyepiece...


I can't post much of an example, it's generally seen in comparison of images at 8x12 and higher.

wxwax

DRT-Maverick wrote:

I know how to set my eyepiece...


I can't post much of an example, it's generally seen in comparison of images at 8x12 and higher.

No problem. If you have a smugmug account, or similar, save the biggest size file they'll permit. Then post a link.

DavidTO

wxwax wrote:

No problem. If you have a smugmug account, or similar, save the biggest size file they'll permit. Then post a link.

or post a 100% crop at 400x600 or some such thing...we don't need to see the whole image, just enough to see the problem.

DRT-Maverick

Here's a photo.



See how blurry that is?

ziggy53

DRT-Maverick wrote:

Here's a photo.



See how blurry that is?

Yep, that's pretty bad. For being shot at 1/320 sec and
f 7.10, it should be better.

I notice that the focal length is 31mm, so was this the Pentax 18-55 zoom or the Sigma 28-200 zoom?

Does the problem occur with any lens? I would be especially concerned if it happens with the Sigma 180mm macro.

ziggy53

DRT-Maverick

ziggy53 wrote:

Yep, that's pretty bad. For being shot at 1/320 sec and
f 7.10, it should be better.

I notice that the focal length is 31mm, so was this the Pentax 18-55 zoom or the Sigma 28-200 zoom?

Does the problem occur with any lens? I would be especially concerned if it happens with the Sigma 180mm macro.

ziggy53

The Sigma. I haven't really used the Sigma 28-200 on this camera much, I don't really like the lens. The Macro comes up with slightly blurred edges lately, nothing as bad as the wide angle, but it's still there.

wxwax

DRT-Maverick wrote:

Here's a photo.

See how blurry that is?

That's truly awful. I don't see a single thing that's in focus.

Is Ziggy correct about the EXIF info?

31mm, 1/320, f7.10?

Was this on autofocus?

JimM

Have you gotten any sharp shots from it?

DRT-Maverick

JimM wrote:

Have you gotten any sharp shots from it?

Yes, it just started happening after my last trip. I didn't drop the camera or anything.

ziggy53

wxwax wrote:

...

Is Ziggy correct about the EXIF info?

31mm, 1/320, f7.10?

...

You dare to doubt the amazing ziggy? Why, I can't remember the last time I was wrong. 'Course, I can't remember if I put on clean underware. (Checking) Whew!

If you want to check for yourself (no, not your underware), just right-mouse-click on the image, save it onto your HD and check it with your favorite method. (Unless you got one o' them Mac thingys, then you're on your own.) Mav left the EXIF in the file.

Thanks,

ziggy53

wxwax

ziggy53 wrote:

You dare to doubt the amazing ziggy? Why, I can't remember the last time I was wrong. 'Course, I can't remember if I put on clean underware. (Checking) Whew!

If you want to check for yourself (no, not your underware), just right-mouse-click on the image, save it onto your HD and check it with your favorite method. (Unless you got one o' them Mac thingys, then you're on your own.) Mav left the EXIF in the file.

Thanks,

ziggy53

Didn't mean to insult you, old boy! Thanks, I didn't know how to do that.

ziggy53

wxwax wrote:

Didn't mean to insult you, old boy! Thanks, I didn't know how to do that.

What insult? I told you I forget things easily. If I could only remember where I stashed my millions?

ziggy53

DRT-Maverick wrote:

Yes, it just started happening after my last trip. I didn't drop the camera or anything.

Maverick,

Sorry, I didn't mean to leave you. Let's start with the basics.

First, clean the contacts that electrically connect the lens to the camera, Since other lenses seem to work OK, concentrate mostly on the lens. Use a plain old pink pencil eraser and gently work against the contacts until they are shiny.

With the lens back on the camera in auto focus, choose something near and something far and see if you can get the lens to try to focus, both in the viewfinder and listen with your ears. See anything wierd or hear anything wierd?

If yes, you have a bad lens that needs to be returned. Case closed.
If not, then it's trying to work, it just can't for some reason.

Check the switch from auto to manual. Purposely move the switch to manual and de-focus. Move the switch back to auto and see how quickly it seeks. Fast or slow?

If slow, you have a bad lens that needs to be returned. Case closed.
If fast, it's trying to work, so continue.

Choose something very distant, at least a half-mile away. A radio or TV broadcasting tower works pretty well. Auto focus and take a shot. Switch to manual focus and try to better the shot. Be patient and do it properly. Take several series at both extremes of the zoom and both wide open and stopped down to at least f8.

Check the results on a computer monitor at 100%. Can you see a difference between manual and auto?

If yes, then the lens is not focussing properly and needs to be returned/repaired/replaced. Case closed.
If no, then the lens will never be acceptable.

One last thing to check.

Shine a small LED flashlight into both ends and look through the lens. Work the zoom and you may see something at one extreme or another.

If the lens looks cloudy at all, it has internal contamination. You will not find the lens to be acceptable until it is returned/repaired/replaced.

Take the above with a little tongue-in-cheek, but that is pretty much the process I would go through to diagnose a soft focus problem.

Good luck,

ziggy53

ziggy53

So ... what happened?

ziggy53

wxwax

Good bump, I'm curious too.