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Old Nov 4, 2004, 12:37 PM   #1
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Hi Steve. I really appreciate your reviews. You have mentioned a few times about problems with digital cameras in low light. It would be extremely valuable information if you could test the cameras similar to a parent sitting in the audience fortheir kid's play - inside but far enough away that the flash doesn't make any difference. Do you have any recommendations?Thanks!!!
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Old Nov 4, 2004, 2:06 PM   #2
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Only one - use a tripod! Even with image stabilization you just can't hold a camera steady enough to capture a non-blurry picture atslow shutter speeds. We have become used to our modern camcorders working well in those low-light conditions but I'm sorry to say that the average still digital camera just can't do it. A more expensive digital SLR with the ISO pushed up to 1600 can just barely do it in that kind of lighting.
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Old Nov 4, 2004, 2:12 PM   #3
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daven123 wrote:
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Hi Steve. I really appreciate your reviews. You have mentioned a few times about problems with digital cameras in low light. It would be extremely valuable information if you could test the cameras similar to a parent sitting in the audience fortheir kid's play - inside but far enough away that the flash doesn't make any difference. Do you have any recommendations?Thanks!!!
A camera must keep the shutter open long enough to properly expose the image, and if shutter speeds are too slow, you get motion blur.

Threefactors control how long the shutter must stay open for proper exposure:

1. Lighting Levels (measured as EV, which is short for Exposure Value).

2. Aperture of the Lens (this is how large the iris is at a given focal length -- that's the hole that lets light through to the sensor). This is measured as f/stop (which is really a ratio between the focal length of the lens and the diameter of the aperture opening).Smaller f/stop numbers equate to larger apertureopenings (hence, a smaller number indicates a brighter lens). Most lenses are rated at both wide angle, and at full zoom (since most lenses lose a lot of light when using zoom). Some lenses only have one rating (for example, f/2.8 , since they are able to maintain their lens brightness throughout their zoom range.

The aperture scale (in one stop increments) 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, etc. With each one stop move to a smaller aperture (represented by larger f/stop numbers), you will need shutter speeds twice as long for proper exposure (or twice as much light for the same shutter speeds).

3. ISO Speed. This is the sensitivity of the sensor to light. Each time you double the ISO speed, a camera can use shutter speeds twice as fast.

Here is a handy chart that will show you how aperture (measured as f/stop), lighting levels (measured as EV), impact the shutter speeds needed for proper exposure. It's based on ISO 100. Each time you double the ISO speed, you can use shutter speeds twice as fast:

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

Let's take an example:

If you are shooting indoors without a flashwith the lighting levelat an EV (Exposure Value) of 6 (typical for well lit interiors) at an ISO speed of 100 and an aperture of f/2.8, the shutter speed needed for proper exposure would be approximately 1/8 second.

Now, the problem with a shutter speed this slow, is that you'll get motion blur (both from subject movement and from camera shake), unless you're using a tripod, and you have a subject that is not moving.

As a general rule of thumb, just to reduce blur from camera shake, you need shutter speeds of 1/focal length or faster (although this is only a rule of thumb, as some users can hold a camera steadier than others).

In other words, if you're shooting at the wide angle position of a lens that's equivalent to 35mm, you'd want a shutter speed of 1/35 second or faster. If you're shooting at the zoom end of a lens that's 200mm, you'd want a shutter speed of 1/200 second or faster. This is because more zoom also magnifies camera movement.

Notice that we are nowhere near these shutter speeds at ISO 100 and f/2.8 (the largest available aperture for most lenses). So, how can we help?

One way is to increase ISO Speed. Each time we double the ISO speed, the camera can use shutter speeds twice as fast. So, if we use ISO 400 instead, our shutter speed would be around 1/32 second (actually the camera usually rounds this), at f/2.8, with an EV (Exposure Value) of 6.

This is STILL slower than needed to prevent blur from camera shake fromsome users without a tripod -- even without using any zoom with most models. Although, it's probably "close enough" for most users at the wide angle lens setting for typical models.

Using zoom is going to compound the problem (because camera movement is amplified as more zoom is used). That's why shutter speeds need to increase as more zoom is used (and why we have the 1/focal length rule of thumb if you aren't using a tripod).

The other problem is that we will have MUCH more noise (similar to film grain) when shooting at ISO 400 with most non-DSLR cameras. This is because increasing the sensitivity of the sensor to light is only amplifying the weak signal generated by the light hitting it. As a result, you also amplify the noise (similar to turning up the volume on a weak radio station with static).

So, getting acceptable photos indoors without a flash (or using a tripod for stationary subjects) is difficult at best.

The best solution is a DSLR model with a bright lens. Because these models have much larger sensors, noise levels are lower as ISO speeds are increased (because the larger photosites for each pixel can gather more light, generating a better signal compared to the non-DSLR models).

They can usually shoot at ISO speeds up to 1600 (or even 3200),whereas even ISO 400 is virtually unusable on many non-DSLR models.

Now, a DSLR will still have noise as ISO speeds are increased (it's just not as bad at equivalent ISO speeds compared to non-DSLR models, and you havemuch higher available ISO speeds).

An example of a lower cost DSLR setups suitable for indoor plays, concerts, etc., would be a Nikon D70 or a Canon Digital Rebel; using a bright lens (like a Sigma 70-200mm f/2.8 EX HSM lens). This lens would allow a constant aperture of f/2.8 throughout the focal range -- with the DSLR allowing higher ISO speeds than possible with a non-DSLR model.

Unfortunately, this lens alone runs around $800.00 discounted (and you still have the cost of the camera and accessories). It's also a much larger and heavier solution compared to the non-DSLR cameras. An even better solution would be one of these DSLR models using a stabilized lens (Nikon makes VR, or Vibration Reduction Lenses; and Canon makes IS (or Image Stabilization Lens). But, the lens cost will usually be much higher with these types of lenses in a bright lens (for example, the 70-200mm Nikkor f/2.8 VR lens runs around $1,600.00 from online discounters).

The benefit of a stabilized lens, is that it reduces blur from camera shake. So, you can usually take photos at settings about 2 stops slower than you can with a hand held camera. Of course, you still need shutter speeds fast enough to prevent blur from subject movement -- even if you use a stabilized lens or a tripod.

So, finding a non-DSLR model that is suitable for indoor events is a challenge.

You'll want to look at models with the brightest lenses possible (able to maintain their brightness well as more zoom is used). Some models are available that can maintain a constant f/2.8 aperture throughout their zoom range now. A few others come close to this.

You'll also want the ability to shoot at higher ISO speeds without too much noise (which is not usually the case with non-DSLR models).

A stabilized lens is also desirable (to reduce blur from camera shake).

Of course, you also need to take things like the ability to focus in lower light into consideration, and well as the usability of the viewfinder, etc.

IMO, there is no "perfect" choice for this type of shooting in non-DSLR models (each one will have some drawbacks).

Even with the above, you'll most likely still have apercentage of photos that are not usable (due to motion blur from subject movementand/or noise from higher ISO speeds needed) from non-DSLR models indoors without a flash.

So, you'll need to take lots of photos to get some keepers (provided you don't need print sizes too large). Also, noise reduction software can help out (to clean up the photos some later). Here are some popular packages:

http://www.neatimage.com

http://www.picturecode.com

http://www.noiseware.com (they have a free version that works well).

If you can get a relatively close seat (where a 190mm lens would do the trick), you may want to take a look at a model like the Sony DSC-F717 (now discontinued, but you can still find 'em). It's lens starts out at f/2.0 on the wide angle end (twice as bright as most other models), and only stops down to f/2.4 at full zoom. It's 5MP 2/3" CCD isn't too bad from a noise perspective, either (compared to other non-DSLR models). But, it does not have a stabilized lens. So, you'd need steady hands (or a monopod or tripod) for best results.

A model like the DiMAGE A1 wouldn't be too bad compared to most other non-DLSR models either (although it's lens starts out at f/2.8 -- stopping down to f/3.5 at full zoom). So, it's nowhere near as bright as the lens on the DSC-F717. But, it does have the advantage of anti-shake (and it's using the same type of 5MP 2/3" CCD as the Sony DSC-F717). It's maximum focal length is equivalent to 200mm on the zoom end (about the same as the Sony).

In the "Ultra Zoom" Category, you may want to look at models like the Panasonic DMC-FZ3 or DMC-FZ15. These have much longer lenses from a zoom perspective, and are able to maintain a constant aperture of f/2.8 throughout their focal range. Their lenses are also stabilized to help reduce blur from camera shake. However, these models have smaller, densor sensors (so noise will be higher as ISO speeds are increased). Their EVF displays also don't "gain up" in lower light.

None of these models is really agood choice for indoor shooting without a flash of moving subjects, compared to a DSLR model with a bright lens. However, these would be models I'd look at if on a budget, and wanted to see if the results would be good enough (understanding that you may not getmany "keepers"due tomotion blur, especially when the subjects are moving, print sizes may be limited, and youwill need to clean up the noise with software).
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Old Nov 4, 2004, 2:23 PM   #4
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Since I don't take the time to get out the tripod most of the time, I was wondering about using a flash for pictures. I have a Sony V3... I was wondering if close-up shots (let's say <8 or so) would make a difference using an external flash as opposed to the internal flash. Sony makes an external flash that is good up to about 50ft. but do you think it would improve shots within a closer range? I would really appreciate your input Steve, JimC,somebody...
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Old Nov 4, 2004, 2:49 PM   #5
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Improve shots in what way? More even lighting, less redeye? Yes.

As far as stopping motion blur, even the internal flash will work fine within the flash range in most lighting.

Shutter speeds are not as critical using flash. This is because the flash itself has the effect of freezing the action. In most (but not all) lighting needing a flash, the subject is not exposed well enough to see any exposure by the ambient light (as long as you don't bumpup the ISO speed or use shutter speed/aperture combinations that let too much light in).

Since the flash duration is very short (usually 1/1000 to 1/10000 second, depending on the flash design, subject distance, and aperture), the flash freezes the subject movement (since the subject is usually only properly exposed for the short flash burst duration).


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Old Nov 4, 2004, 2:50 PM   #6
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Thanks guys for the replies. I appreciate the information. I guess I still come back to the fact that sincedifferent cameras have different sensor sizes and different lense speeds, that each camera will be different in it's ability to handle this type of situation. Many times there is a lot of light on stage and not much movement, whichhelps. I think it would be extremelyvaluableinformation for a lot of peopleif there wasa comparison of each camera's performance under this type of situation. Also, if such a comparison was common-place, the camera manufacturers may start making cameras that are better under this situation (versus racing to making them postage stamp size).

Thanks again!

Dave
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Old Nov 4, 2004, 3:30 PM   #7
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Thanks JimC... Yes, I guess what I am asking is will I get more even lighting using an external flash. I am pretty satisfied with my indoor pictures using my internal flash, but some pictures do have dark corner (kind of a vignetting effect) and the background is often very dark. Thanks in advance for any more insight you may have!
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Old Nov 4, 2004, 3:58 PM   #8
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stallen wrote:
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Thanks JimC... Yes, I guess what I am asking is will I get more even lighting using an external flash. I am pretty satisfied with my indoor pictures using my internal flash, but some pictures do have dark corner (kind of a vignetting effect) and the background is often very dark. Thanks in advance for any more insight you may have!
Using an external flash allows you to more evenly disperse the light (bouncing it from the ceiling is one technique for doing this).

You can also get add-on's to help diffuse the light (like the Sto-fen Omni-Bounce). You can see some of their products here:

http://www.stofen.com/

I have an old Vivitar Flash ona 35mm that I have a Vivitar"Soft Light/Bounce Diffuser Kit" for that I usein some shooting conditions to more evenly disperse the light (it's a white board that sits behindthe flash for bouncing the light).

The reason it's dark behind your subject is because the flash must "throttle down" for closer ranges to keep from overexposing your subject. As a result, the background is usually much darker. Bouncing a flash will help with gettting more even lighting.

You may want to ask some questions in the lighting [flash] forums about techniques to use for this purpose. There are many users here far more experienced than I am with lighting techniques and flash use.


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Old Nov 4, 2004, 4:10 PM   #9
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Thanks again Jim for the information...

My topic seems to have been hi-jacked (maybe time-shared is a nicer term)...
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Old Nov 4, 2004, 5:20 PM   #10
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daven123 wrote:
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Thanks again Jim for the information...

My topic seems to have been hi-jacked (maybe time-shared is a nicer term)...
Yes - - sorry about that. However, the question was somewhat related (trying to figure out how to get better photos indoors).:-)

I can't speak for Steve (and he made his thoughts perfectly clear on the subject). But,asfar as testing cameras in a stage environment, I don't personally think it would be very practical, either.

Yes -- given good enough stagelighting with spotlights,a goodphotographer, a bright lens,keeping viewing sizes smaller, etc., you can get away with usable photos sometimes (especially at smaller sizes on screen, since this tends to mask both blur and noise so that it's not as noticeable).

But, IMO the conditions are going to vary too much, and the vast majority of models would not work well enough to produce acceptable quality in many user's eyes (especially at larger sizes). Of course, quality is subjective. ;-)

Also, users may assume that they would get similar results with the same models indoors without a flash or tripod (and again, conditions would vary too much to make these assumptions valid).

There is a reason thatmany models incorporate a camera shake warning if you force flash off: to tell you that lighting conditions are too low, requiring shutter speeds too slowto prevent blur without a flash or tripod. That's the conditions you'd have indoors with most models, at most focal lengths.

It can be a challenge to get sharp photos outdoors at longer focal lengths without a tripod -- much less indoors where you may only have a fraction of the light.

If you really expect to get good quality photos indoors without a flash -- buy a DSLR with a bright lens (and even then, some users may be dissapointed in the quality in lower light and higher ISO speeds).


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