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Old Aug 28, 2009, 8:07 AM   #31
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just take my a230..but seen hard to used it...maybe because i'm new?
another question is when shooting in indoor even the steady shoot function is on why the photo also blur...is it my hand shake?
but my mode is using auto mode without flash...

Last edited by michaellee2222; Aug 28, 2009 at 8:32 AM.
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Old Aug 28, 2009, 8:44 AM   #32
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Your shutter speeds are probably too slow. The camera needs to keep the shutter open long enough to expose the image properly, which will depend on the lighting levels (and typical indoor lighting is very dim to a camera), aperture setting (with lower f/stop numbers representing wider aperture openings), and ISO speed (which is how sensitive the camera is to light).

Indoors without a flash, you'll usually need to use a very high ISO speed with a wider aperture setting using a very bright lens if you don't want blurry photos from subject movement and/or camera shake (and you'll have limits as to how slow your shutter speeds can be, even using stabilization). IOW, you'll probably want to use a flash indoors.

I'd post photo here so that we can tell what's going wrong. I'd suggest downsizing it using something like the free Irfanview. After opening an image with it (File>Open), look under Image>Resize/Resample. I'd make the longest side around 800 pixels or so, leaving the retain aspect ratio box checked. I normally select the Lanczos algorithm for resizing. Then, when you save the image after resizing (File>Save As), select jpeg as the file type and set the JPEG Quality slider you'll see pop up to around 80%. That will probably get the file size within limits as long as the image is downsized to smaller dimensions first. Make sure to leave the retain EXIF box checked so that members can see the metadata for camera settings used.

Then, use the attachment button you'll see when making a post here, which lets you upload an image and attach it to a forum post (use the button in the editor tool bar that looks like or , depending on the forum theme you using).
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Old Aug 28, 2009, 8:51 AM   #33
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ok tonight i will try more shoot adjust the shutter speeds,after try i will post it up then only tell whats going wrong...thanx jimc
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Old Aug 28, 2009, 9:12 AM   #34
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You can't use any shutter speed you want to. If you use a shutter speed that's too fast for the lighting levels, ISO speed and aperture setting, you'll get an underexposed (too dark) photo. If you use a shutter speed that's too slow for the lighting levels, aperture setting, and ISO speed, you'll get an overexposed (too bright) photo. ;-)

If you were using one of the Auto modes, the aperture setting (f/stop) was probably set to it's widest available setting anyway in low light. So, the camera needed to use a shutter speed slow enough to probably expose the image for the lighting level and ISO speed being used. Note that each time you double the ISO speed, you can use shutter speed twice as fast for the same lighting and aperture.


You have 4 main variables to take into consideration for exposure (and I use the term "main" since there are a lot of nuances to how you measure the light (for example, your metering mode), as well as different film characteristics if shooting film, and camera settings if shooting digital for the desired tone/contrast curve within an image and more). Once you have a better idea of how these 4 variables work together to give you a properly exposed image, the other fancy features will make more sense. These variables are light, aperture, ISO speed and shutter speed.

Light is typically measured as EV for Exposure Value in Photography.

Aperture (which works similar to the pupils in your eyes, where you can open up the aperture iris wider to let in more light, or close it down to let in less light). If you let in more light with a wider aperture, you can expose the film or sensor faster. If you let in less light with a smaller opening, it takes longer to expose the film or sensor. Note that aperture is normally expressed as f/stop, which is a ratio between the focal length of the lens and the diameter of the aperture iris. So, smaller values represent a larger iris diameter.

When you vary the aperture, you're controlling the iris in the lens (which like a pupil in your eye, can be opened up to let in more light or closed down to let less light in). So, this impacts the shutter speeds you'll need for proper exposure (since more or less light is getting through to the sensor). Aperture also impacts Depth of Field.

The aperture scale in one stop increments (with larger than f/1 apertures possible but very rare in lenses) goes f/1.0, f/1.4, f/2.0, f/2.8, f/4.0, f/5.6, f/8.0, f/11, f/16, f/22... With each one stop move to a smaller aperture (represented by higher f/stop numbers), you will need shutter speeds twice as long for proper exposure for the same lighting and ISO speed (only half the light gets through compared to a one stop larger aperture).

ISO speed. This is how sensitive the film or sensor is to light and is the same thing as the older ASA rating for film. The higher the ISO speed, the faster you can expose it (each time you double the ISO speed, you can use shutter speeds twice as fast for the same lighting and aperture.

Shutter Speed is how long the camera's shutter stays open to expose the film or sensor).

IOW, it all boils down to how sensitive the film or sensor is to light (which you control via the ISO or ASA speed of the film you use with film, or the ISO speed settings you use with digital), and how much light you need to let it see to "expose" the image (which you control via the aperture opening size and shutter speed).

These exposure calculators and simulators may help you understand it better.

http://www.robert-barrett.com/photo/...alculator.html

http://www.photonhead.com/simcam/shutteraperture.php

Note that aperture also influences depth of field. See this handy calculator for more information about it:

http://www.dofmaster.com/dofjs.html
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Old Aug 28, 2009, 9:15 AM   #35
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Shorter version:

The camera was probably using it's widest available aperture anyway if you were using one of the Auto modes. So, the main setting you could try to change to get faster shutter speeds would be your ISO speed setting. Note that if you set ISO speed higher, noise levels will be higher. If you don't zoom in as much, that can help, too (as your lens is brightest at it's widest zoom setting).

With a typical kit lens (with a widest available aperture of f/5.6 if you zoom in much), you'll probably want to use a flash in most indoor lighting.

But, so we can make sure that's what is going wrong (shutter speeds are too slow resulting in blurry photos), I'd post a downsized sample so we can see the camera settings being used for aperture, iso speed and shutter speed (that information is in a header inside of the image).
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Old Aug 28, 2009, 9:36 AM   #36
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JimC, I've read all your explanations on the cuases/possibilities of blurry indoor pictures, but if the user has the camera set to auto and camera shake to ON, why would this even happen ?...I thought Sony was going for the newbie market to avoid playing around with the manual settings.
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Old Aug 28, 2009, 9:41 AM   #37
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Anti-shake can only help so much if light is too low (and indoor lighting can be much dimmer than it appears to the human eye, especially at night with no ambient light coming in through windcows). That's why the camera has a flash. ;-)

The A230 will even pop up the flash in green Auto mode when light gets too low. So, that tells me the OP was probably using one of the other modes if shooting without a flash. We could tell what went wrong by looking at the EXIF information in a downsized sample (for example, setting an ISO speed too low, using an aperture too small if using a non-Auto mode, etc.)
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Old Aug 28, 2009, 9:56 AM   #38
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There are three adjustments you can make to control the exposure. In Auto Mode (as well as P Mode), you're leaving two of them up to the camera; you select the ISO, and the camera selects the shutter speed and aperture. The camera's natural inclination is to stop the lens down a little, and use a shutter speed that provides a correct exposure. Indoors, that shutter speed is likely to be slow enough so the resulting image might include some motion blur.

Motion blur comes from two sources: Camera shake, which the SSS can do somethings about and is relatively sucessful, and subject movement, which the camera can't help you with.

You can reduce the effects of both types of motion blur by shortening the shutter speed, but in order to get a proper exposure, you need to increase the ISO, risking noise, or open the aperture. The problem is that the kit lens (most lenses, in fact,) can't open very far, so your choice comes down to motion blur or noise. You can use more light by using a flash, or you can use a larger aperture by getting a faster lens. For indoor shooting, Sony's 50mm f1.8 ($150) or Minolta's 50mm f/1.7 (~$100) are good choices.

Shooting indoors in available light is tough. SSS doesn't change the rules of photography; it just helps you stay within one of them.
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Last edited by TCav; Aug 28, 2009 at 9:59 AM.
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Old Aug 28, 2009, 9:57 AM   #39
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P.S.

The most common cause of blurry photos indoors is trying to take them with the flash forced off when light is too low, resulting in shutter speeds that are too slow. That's what I suspect is happening here. But, without a downsized sample, we won't know what went wrong.
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Old Aug 28, 2009, 10:34 AM   #40
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This was shot in my living room in available light.



It's my son tickling his son.

It was shot at 1/30 second, f/2.8 at ISO 400, and a focal length of 40mm. The shutter speed is about half what it should have been to prevent motion blur due to camera shake, but the image stabilization took care of that. But my grandson was laughing and trying to get away from his father, so there is some motion blur from subject movement, most noticeable on his glass frames and the gap where he lost his front tooth.

This was shot at a friend's house at night.



It's of my brother-in-law holding his new nephew.

It was shot at 1/6 second, f/2.8 at ISO 800, and a focal length of 50mm. The shutter speed of 1/6 second is WAY TOO SLOW to shoot handheld, but the subjects were motionless during the shot, I was able to steady myself, and image stabilization limited the motion blur to an acceptable level.
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