Go Back   Steve's Digicams Forums > Digicam Help > Newbie Help

Thread Tools Search this Thread
Old Jan 31, 2004, 5:03 AM   #11
Senior Member
Join Date: Jan 2004
Posts: 824

Focusing is a light and optics issue (what you see is what you get); that means that if the image isn't focused when it hits the CCD sensor, it'll never be focused. You can't use software to focus an originally unfocused shot. Of course, you can do things with software to improve a marginal situation (sharpening and so on), but the basics still apply.
I'm not sure what you mean about RAW data keepng the focus; SFAIK, the EXIF data doesn't include specific focusing information (e.g., measured distance to subject). On the other hand, all of the formats (RAW, TIFF, JPEG) keep the light (optical) information that comes through the lens and strikes the CCD; that obviously includes the "focus," if that's what you mean.

For now though, I'd agree with your last suggestion that you go outdoors on a sunny day, mount the camera on a tripod, and try photographing a variety of subjects/distances, and see how the focus turns out. Start with the zoom set at its widest setting, and be sure your subject is in the center of the viewfinder. Try various stages of the zoom. Remember that the zoom probably won't focus on very close objects when it's set for its highest telephoto (10x) setting. I don't know much about your specific camera, so it's up to you to read the instructions and be sure of things like where the camera is focusing--e.g., most cameras have a focus rectangle in the center of the screen that indicates where they're focusing, but that focus box can jump around on some cameras/settings so you have to understand what it's doing.

Good luck.
Norm in Fujino is offline   Reply With Quote
Old Jan 31, 2004, 8:24 AM   #12
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,371

Originally Posted by twl
Thanks again for all of the info. Maybe i'm jumping the gun abit on the camera being defective (since almost all my pictures were taken indoors with poor lighting, letting the camera choose all the settings)..

Im going to spend a few hours in the afternoon trying different shots and see how things turn out..

One final question though (well two I guess),

Can focusing issues (ie. blur) be easily fixed with software like lighting issues can?

And is focusing saved in the RAW file (from what I understand a RAW file contains no camera enhancements, is focusing an anhancement or just a given)..
Again, it is extremely unlikely (based on the photos I've seen, and your comments on the amount of zoom used), that your problem is anything other than motion blur.

Unfortunately, without flash, you cannot expect to get acceptable quality photos with your camera using zoom indoors (shutter speeds will be too slow).

Even at full wide angle, unless light is very good, and your hands are VERY steady, it's unlikely you'd get good photos without motion blur with the lighting level in your photos.

The example you gave us, using a 1/3 second shutter speed at ISO 200 indicates that the problem is simply motion blur due to low light levels.

If I'm VERY careful, bracing myself, I can sometimes get sharp photos at 1/8 second (with more light than in the example you posted), at full wide angle. However, this is the exception to the rule.

Most users will need much faster shutter speeds to eliminate blur from camera shake in similiar lighting conditions and focal lengths.

No, you cannot fix motion blur with software.

Basically, even though 1/3 second may sound fast. It's not. At full wide angle without flash, you'll want a shutter speed around 10 times as fast. That would mean dramatically better light levels would be required.

As mentioned before, using zoom, your shutter speeds need to increase proportional to the amount of zoom used, too.

So, my advise would be to always use flash in similiar lighting conditions. If you want to reduce the grain you are seeing (which is actually noise), then lock ISO speed to a lower level (versus the ISO 200 selected by the camera) -- again, making sure to use flash indoors in similiar lighting.

Unfortunately, any consumer digital camera is going to have similiar limitations in the same lighting (especially a "super zoom" model with a small CCD sensor). These sensors require a lot of light to work properly. Light is a Digital Cameras best friend.

What is bright to the human eye, is not to the cameras lens.

Refer to my previous post for the chart on EV levels and shutter speeds needed in various lighting conditions. Again, keep in mind that you will want to have enough light to achieve a shutter speed approximately equal to 1/focal length for a handheld camera.

In other words 1/37 second at wide angle, increasing proportionally as zoom is used to 1/370 second at full zoom. Yes, you can do better with practice (bracing yourself, slowing squeezing the shutter button, etc).

However, not at 1/3 second. I doubt that I could get sharp photos at this slow of a shutter speed at wide angle -- much less using around 7x zoom that you mentioned (which would work out to a focal length of around 260mm). You'd need DRAMATICALLY faster shutter speeds to prevent blur.

Using Flash, shutter speeds this fast are not necessary (because the flash is a very fast burst of light, which helps to freeze the subject). But, without flash, much faster shutter speeds are needed to prevent motion blur.

The focal length of your camera's lens is very nice for bringing the subject much closer. However, your camera has limitations. Using it indoors in low light without flash (especially at longer focal lengths) is one of those limitations.

Practice with your camera, learning to better understand it's strengths, while working around it's limitations.
JimC is offline   Reply With Quote
Old Jan 31, 2004, 9:16 AM   #13
Junior Member
twl's Avatar
Join Date: Jan 2004
Posts: 18

Thanks Jim (and everyone else for your comments), I've been playing around this morning and all of my out of focus pictures are using 1/3 shutter speed. The camera seems to default to this in automode. My old camera sets the speed at 1/32 of a sec for the same picture. I've decided to ignore automode from now on and start taking control.

Once I adjusted the shutter speed the blur vanished.. I feel much better now, and this problem has given me the push I needed to start learning more about photography then just Point and Shot..

Here is my first working picture:

I manually added it to my web, so hopefully it contains the picture info..
twl is offline   Reply With Quote
Old Jan 31, 2004, 9:56 AM   #14
Senior Member
Join Date: Oct 2003
Location: Indian Rocks Beach, FL
Posts: 4,036

I've been playing around this morning and all of my out of focus pictures are using 1/3 shutter speed. The camera seems to default to this in automode. My old camera sets the speed at 1/32 of a sec for the same picture. I've decided to ignore automode from now on and start taking control.
Most program modes on quality digital cameras will not go below the reciprocal of the focal length rule for the shutter speed until the lens is completely open. There should be no shutter speed advantage messing with manual, shutter or aperture priority. Once the lens is all the way open the camera is letting the correct amount of light to the sensor by adjusting the shutter speed, and if that works out to 1/3 second there is no magic you can do with the controls that will give a properly exposed shot at a faster shutter. You are spinning your wheels trying to “take control” in that particular situation.

You can raise the ISO giving a noisy shot, but that works just as well in program mode as well.

Take both of your cameras indoors. Zoom them both to full wide. Pre-focus and look at the shutter speed. If there is much difference between them there is something wrong. No way the Toshiba could be 1/3 sec and the old camera 1/32 under the same lighting conditions and focal length. It is a mathematical derivation with the only difference being glass loss, and I can’t believe the coatings on the Canon lens on the Toshiba are that bad.

Did you set the camera on a solid table and take the 1/3 second (no flash) shot using the self timer? If there was still blur something isn’t right. Maybe the low light focus is poor – you just have to learn to compensate if that is the case.
slipe is offline   Reply With Quote
Old Jan 31, 2004, 9:59 AM   #15
Join Date: Jun 2003
Location: Savannah, GA (USA)
Posts: 22,371

Yes, your latest photo does include the EXIF data.

I see that you used flash for this photo, and it was taken at near wide angle.

This is why the camera was able to use a faster shutter speed (because flash was used).

The camera is using a 1/3 second shutter speed in your other photos, because flash was not used. In order to properly expose a photo indoors without flash, the camera has no choice but to use a slower shutter speed (which is why you were getting motion blur).

Just like a film camera, a Digital Camera needs to keep the shutter open long enough for proper exposure for the aperture used. In a film camera you're exposing film. In a Digital Camera, you're letting light focus on the CCD Sensor (which is acting as film -- only using millions of photosites to do the same thing).

This forum is a great way to get feedback on any issues with a digital camera. I'm sure others will be willing to help, too if similiar issues arise.

I'm glad you are feeling much better about your camera.

Once you practice with it, learning it's strengths and limitations, you'll be taking consistently good photos in no time!
JimC is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -5. The time now is 7:16 AM.