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Old Jun 1, 2004, 5:14 PM   #1
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I'm new to digital cameras... visited a church last weekend that had some light but wasn't sufficient for the camera... flash range didn't reach so I ended up with dark pictures.

What would be the best method for getting more properly exposed pictures in this kind of setting? (indoor, medium light, large facility) No tripod, btw.

Thanks for any feedback.
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Old Jun 1, 2004, 7:13 PM   #2
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What is bright to the human eye, is not to the camera's lens. What you are referring to as "medium lighting" is probablyVERY low lighting.

Based on your previous posts, I see that you have a new 6MP Casio EX-P600, and have already discovered that you'll get motion blur without a flash.

A typical indoor environment has an EV value of around 6. So, at ISO 100 and F2.8 (the maximum aperture of the lens in your camera); a shutter speed of around 1/8 second would be needed for proper exposure. This is way too slow to prevent motion blur for most users (even at maximum wide angle). So, flash is needed.

You can increase ISO speed to help compensate (but this increases noise). This is the "grain" you see (multi-colored dots in image).For exampe: you could use ISO 200 to get a shutter speed of 1/16 second in these conditions (still too slow to prevent blur from camera shake for many users at wide angle).

So, ISO 400 is probably needed without flash (and it would likely have very unacceptable noise levels).

With your 6MP 1/1.8" CCD,the size of the photosites for each pixel is very small. As a result, more amplification of the signal is needed to get the same equivalent ISO sensivitity (compared to a less dense CCD, with larger photosites for each pixel). Amplification of the signal from the sensor increases noise.

See this chart for more details. It's based on ISO 100. So, each time you double ISO speeds, you can double the shutter speeds in the chart:

http://home.earthlink.net/~terryleedawson/dcnotes/tables.htm

So, you'll probably need to use flash indoors with this camera in almost any situation to prevent blur (even at full wide angle). Although, you may be able to get away with it bumping up ISO to 400(if you stick to smaller print sizes and use noise reduction software).

Some suggestions:

* Shoot at full wide angle whenever possible indoors. This allows more light to reach the sensor through the lens

* Stay within the stated flash range for properly exposed images.

* Consider a Slave Flash. These are designed to fire at the same time as the camera's built-in flash. You'll need to experiment to get proper exposure.

* Increase ISO sensivity when absolutely necessary, but be prepared for a lot of noise at higher ISO speeds. Try using software to reduce it (Neat Image or Noise Ninja). You can download trial versions here:

http://www.neatimage.com

http://www.picturecode.com

* Buy a camera better suited for existing light photography. I'd suggest looking at something like the Canon Digital Rebel (EOS-300D), or Nikon D70. These cameras have DRAMATICALLY larger sensors, compared to the tiny 1/1.8" CCD in your existing camera. As a result, the photosites for each pixel are MUCH larger. This allows for shooting at much higher ISO speeds with lower noise. Keep in mind, that you'll still want a "fast" (brighter) lens to go with the camera you choose (the "kit lenses" are not bright enough for this purpose).
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Old Jun 1, 2004, 9:09 PM   #3
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Thanks very much for the reply, JimC. A few questions:

1) When I don't use flash, is the blurring I get due to smy hand shaking (low shutter speed), or simply not enough light to focus perfectly?

2) Shooting at full wide angle... so at a 2.8 aperture, will this negatively affect any other aspects of the picture?

3) So, as MP increases, noise increases as well? I've shot at ISO200, and the noise seems bad although the specks are small and all over the picture.

4) And finally, I guess all cameras have this kind of trouble? Seems like people with cheaper cams that simply point-and-shoot and get better indoor shots so I was frustrated at first... but if not, then, well :?

5) edit, noticed one thing when I was shooting at 1/8 shutter speed, 2.8 aperture, and ISO 100. Pictures came out a bit grainy (on the LCD, that is, but I can't confirm it)- why would that be, considering I shot at ISO100?

Thanks again, appreciate it.
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Old Jun 1, 2004, 10:02 PM   #4
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nbie wrote:
Quote:
1) When I don't use flash, is the blurring I get due to smy hand shaking (low shutter speed), or simply not enough light to focus perfectly?
It's probably camera shake if you're using anything under ISO 400 indoors without flash. As a general rule, you'll need a shutter speed of 1/focal length or faster to prevent blur from camera shake.

In other words, at 33mm equivalent focal length (full wide angle on your camera), you'll want to use a shutter speed of 1/33 seconds or faster. At 132mm equivalent (full zoom on your camera), you'll need a shutter speed of 1/132 second or faster to prevent blur from camera shake.

About theonly way you're going to get fast enough shutter speeds indoors (in most lighting conditions), without flash, is to use full wide angle and ISO 400. This will most likely result in very unacceptable noise levels.

nbie wrote:
Quote:
2) Shooting at full wide angle... so at a 2.8 aperture, will this negatively affect any other aspects of the picture?
You will have less depth of field at your camera's widest aperture (but it will select this aperture anyway in low light -- you don't need to do it). As far as shooting at full wide angle, you will probably have a little bit of barrel distortion, and may have more of the photo in focus than desired (greater depth of field at wide angle). However, in low light, you don't really have much of a choice with this model, unless you want to invest in auxillary lighting/slave flashesfor indoor shots.

nbie wrote:
Quote:
3) So, as MP increases, noise increases as well? I've shot at ISO200, and the noise seems bad although the specks are small and all over the picture.
Yes and No. If a manufacturer puts more pixels in the same size area, then yes -- you'll have higher noise as megapixels increase in most cases. However, if the CCD sensor is larger, then this is not the case.

As a general rule, in your CCD size (1/1.8" or .556"), the 5 Megapixel Models had higher noise than the 4 Megapixel Models, and the 6 Megapixel Models should have even higher noise.

But, if you go to a DSLR with a larger sensor, then 6 Megapixels is not a problem. It boils down to the size of the photosites for each individual pixel -- not the number of Megapixels. But, since manufacturers are trying to pack a LOT of pixels into a small CCD with these newer 6MP non-DSLR models, noise will increase.

Firmware (in camera processing of the images) can also make a difference in noise. Some manufacturers do a better job compared to others in controlling it. But, the biggest thing is the size of the photosites for each pixel. With the new generation of smaller, denser CCD's; noise can be a problem at anything other than the lowest ISO Speed settings.

nbie wrote:
Quote:
4) And finally, I guess all cameras have this kind of trouble? Seems like people with cheaper cams that simply point-and-shoot and get better indoor shots so I was frustrated at first... but if not, then, well :?
It depends on the camera. Some models may be using CCD Sensors with better noise characteristics, compared to your Casio. Personally, I would not buy a 6MP Consumer(non-DSLR)Model, if I wanted to use anything over ISO 100.

nbie wrote:
Quote:
5) edit, noticed one thing when I was shooting at 1/8 shutter speed, 2.8 aperture, and ISO 100. Pictures came out a bit grainy (on the LCD, that is, but I can't confirm it)- why would that be, considering I shot at ISO100?
You can't really go by the LCD display. These displays are relatively low resolution, and so you can't really tell what the photos will look like on screen.

However, yes it's still possible to have noise at ISO 100. Basically, noise is much worse in underexposed areas of a photo. Think of underexposed areas of your cameras's CCD sensor as sound amplifiers with no audio input. Witha sound amplifier, you get "hum and hiss" when the input level is too low. With the CCD Sensor, you get image noise when the input level (light) is too low.


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Old Jun 2, 2004, 7:00 PM   #5
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Once again, a big thank-you Jim.

One last question. As for exposure, does it make a difference where I focus the camera on? As in, on a bright or dark place?
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