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Old Sep 2, 2004, 10:10 PM   #1
SSD
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I got my DigitalRebel today and I took it out this evening to photograph a friends son play baseball. What is wrong with the attached pic? Almost all of the pictures came out like this and it was not even dark outside. It was very early evening and cloudy. There should have been enough light for these pics to come out. I need to figure this one out before tomorrow's football game. :?

(I do own the 550EX flash, but I have no idea how to use it, I am a total newbie at this kind of stuff, usually do point and shoot stuff)
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Old Sep 2, 2004, 10:50 PM   #2
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My guess is you had the flash mounted but it was turned off. I don't know exactly how the Rebel handles the flash. If it sets up the exposure for flash anytime the flash is mounted, that would probably set the shutter speed to 1/60 or 1/125.

On my Nikon D100, if the flash is mounted but turned off, the camera ignores it. If the flash is turned on, the camera sets up for a flash exposure.

Your shots look like the flash didn't fire. Are you sure the batteries in the flash are good (or even installed)? You should have a battery indicator showing the battery condition. There should also be a red light indicating when the flash is ready to fire. When you first turn on the flash, you should hear a high pitched squealing sound. That is the internal capacitor charging up to the voltage required to fire the flash. If you shoot your picture before that light comes on, the flash won't fire. The capacitor recharges after every flash.

Again, since I am not familiar with the Canon equipment, my suggestions are general in nature.

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Old Sep 2, 2004, 11:00 PM   #3
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Hi

Thanks for your reply! I took several pics with the built in flash that came out dark and then several with the 550ex mounted and turned on. The flash fired every time and those pics were black too. I am a newbie and lost on this one.


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Old Sep 2, 2004, 11:42 PM   #4
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That looks like you used a shutter speed much higher than the flash sync speed of your camera. In this respect, the shutter opens and closes before the flash goes off - flash is out of sync with the shutter. Sometimes you may get partial flash on part of the image because the flash fired just as the shutter was closing, therefor only part of the frame registered the flash of light. If that is not the problem, severe under exposure has occured, maybe you had the camera set on manual mode.
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Old Sep 3, 2004, 12:20 AM   #5
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On the Nikon, the shutter speed is set to synch speed whenever the flash (internal or external) is active. That may not be true for the Canon. Check your flash manual for the basics. The manual may contain a lot of advanced information which you may never need to use. Also look in your camera manual for a section on flash photography. It should tell you what to do for either internal or external flash.
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Old Sep 3, 2004, 12:32 AM   #6
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It looks to me like your flash was on but the subject was too far away for the flash to be effective but the settings on the camera were for the flash. Was this a with or without flash shot?



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Old Sep 3, 2004, 2:31 AM   #7
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That photo was taken at ISO 100, 1/200 second, f/11, at a focal length of 135mm with flash.

Stopped down tof/11, your internal flash would have been good out to 3.9 feet at ISO 100, or the 550EX would have only been good out to around 16.4 feet (it has a Guide Number of 180 feet/ISO 100, and you need to divide the Guide Number by the Aperture to determine flash range). But, this Guide Number may not be the same, depending on flash mode and focal length (it could be much lower than 180 at times -- read your flashmanual).

The bigger question is why were you at f/11.... Where was your mode dial? According to the EXIF, the maximum aperture should have been f/5.6 with whatever lens you were using. You used PSCS for downsizing the image, so it probably stripped out some of the specifics, but something caused it to pick f/11. Could you have been in A-DEP mode? Judging from your model's review, this mode tries to insure all of the focus points are in focus (but this will force smaller apertures, represented by larger f/stop numbers). Getting more Depth of Field has a penalty -- not as much light can reach the sensor through the lens using smaller apertures.

As for the 1/200 shutter speed, I don't know why it would have picked that -- unless that's what it's trying to use for flash photos (I don't own one, so I don't know it's behavior in this area); or you were using Exposure Compensation and had it set to -EV, forcing faster shutter speeds causing an underexposed photo. I do see a flash sync speed of 1/200 secondin the specs, so that's probably why it was using it.

I don't own your model, so I'm speculating as to why it picked the Aperture and Shutter speed it did.It could have even been a combination of factors (you using A-DEP modeforcinga smaller aperture, with the camera picking 1/200 second for flash sync -- resulting in underexposed images because you forced flash). I find it hard to imagine that full auto would not have done a much better job (not stopping the aperture down to f/11, etc., unless you changed*something* on the camera from the defaults).

If you want to figure out why it did what it did, you'll have to tell us where the mode dial was, if you forced flash, or if you changed anything else from defaults.

If you're going to shoot kids playing ball outdoors, you need to make sure the camera is using the fastest shutter speeds it can, while still maintaining proper exposure. This means larger apertures (smaller f/stop numbers) to let more light through the lens to the sensor if light gets lower. You'll have a bit less depth of field at larger apertures, but that's better than underexposed and/or blurry photos.

Your camera has a sports mode, so I would use it. The way most cameras work is they'll automatically select the largest available aperture (which appears to be f/5.6 for your lens, at the focal length you were at), allowing the fastest shutter speeds possible for proper exposure. If you want to do the same thing yourself, use Aperture Priority Mode (Av on your mode dial), and select it yourself by spinning the control wheel (look for the smallest f/stop number). It would probably be easier to just use the Sports Scene mode if you don't have a good understanding of how these things work.

I'd also increase ISO speed if you're going to be shooting kids running around in lower light. You were at ISO 100. Each time you double the ISO speed, the camera can use shutter speeds twice as fast. This will have the impact of increasing noise (similar to film grain), so don't increase ISO speed any more than you have to.

I'd probably forget the flash unless it's dark enough for it. Since your photo was taken at 7:17PM (if the camera's internal clock was set correctly), you probably didn't even need it then, if you would have used a higher ISOspeed. Sunset would not have been for another 45 minutes. So, ISO 400 would have been plentyfor this time of day if you weren't using f/11. At an EV (Exposure Value) of around 12 (probably about what the light was that time of day if your camera's clock is right), ISO 400 and f/5.6 would have given you shutter speeds of about 1/500second.

When you do need flash (much closer to sunset), your 550EX has a Guide Number of 180 feet (ISO 100, 100mm focal length). Toestimate flash range, you need to divide the Guide Number by the Aperture used. For example, if yourlens has amaximum aperture of f/5.6 at a 100mm focal length (amount of zoom), you'd have a range of around 32 feet at ISO 100. Each time you double the ISO speed, your flash range increases by 1.4x.

I don't own your flash either, so you'll need to read the manual. Chances are, the Guide Number will change depending on your focal length and what flash mode you're in. So, the range may be much lower depending on how you're using it. If I'm not mistaken, it's got a distance readout on it; so I'd suggest learning how to use it to make sure you're inside of the flash range when you do need the flash.

For your upcoming football game, I'd shoot in sports mode -- increasing ISO speed as necessary to get fast enough shutter speeds to prevent motion blur. But, don't increase it any more than necessary. Hopefully, you're talking about a kids game in daylight.

If you're talking about a game in a stadium at night, you're going towant a brighter lens than the one you appear to have (since chances are, your flash will be useless from the stands).You mayneed to increase ISO speeds up to1600 -- just to try and get some keepers withoutblur from camera shake and subject movement in a night game under stadium lights (and this will cause alot of noise). For this type of event,it's advisable to get a lens that can maintain a constant f/2.8 aperture throughout it's focal range.
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Old Sep 3, 2004, 6:20 AM   #8
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Hi

Thanks for all of the replies!

JimC

My camera was set on Sports mode or auto for every picture. I had bumped up the ISO to 400 and 800 after the few I took on 100 and still got dark shots. That is what puzzled me because it was not even dark yet.

My game will be in a stadium tonight with lots of bright lights! The game starts at 7:30

I have lost my flash manual and I am going to have to contact Canon about getting a replacement.
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Old Sep 3, 2004, 10:01 AM   #9
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SSD wrote:
Quote:
My camera was set on Sports mode or auto for every picture. I had bumped up the ISO to 400 and 800 after the few I took on 100 and still got dark shots. That is what puzzled me because it was not even dark yet.
You should not have needed the flash that far before dark. I guess it's possible that Autoexposure selected F/11 to try not to go wide open on the lens (which appears to be f/5.6 for the focal length you were at); but itseems very unlikely it would have did this.

Sports Mode should have also gone to the largest aperture, and increasing ISO speed should have also prevented underexposure.

So, something is probably screwing up the autoexposure (or the metering is not working right on your camera).

Are you sure you didn't change anything else on the camera? Try resetting your camera to factory defaults under Setup page 2 (the menu choice will be "clear all settings"):

http://www.steves-digicams.com/2003_.../300d_pg4.html

What lens are you using on it?

Are the symptoms the same with a different lens?

Are the symptoms the same without flash?

Note, because your lens is so slow (the EXIF showed a maximum available aperture of f/5.6), I would not attempt to use flash tonight (in case it's trying to sync at 1/200 second, since you'll be outside of the flash range anyway in the stadium seats).


Quote:
My game will be in a stadium tonight with lots of bright lights! The game starts at 7:30

What is bright to the human eye, is not to the camera's lens. The light levels in a well lit stadium are typically around EV 8 (much lower than you would have had in cloudy skies 45 minutes before dark).

So, to get shutter speeds up to around 1/125 second at f/5.6 (provided your camera uses the largest aperture of f/5.6 for the lens you are using), you'd need to have ISO set to 1600.

The "rule of thumb" is shutter speeds of 1/focal length or faster. I can't tell what lens you have from the EXIF, but this means for a 100mm equivalent focal length (and you need to use equivalent for shutter speeds needed, not actual), you'd need shutter speeds of 1/100 second or faster -- just to prevent blur from camera shake.

If your focal length was exactly as it was yesterday at 135mm; then the 35mm equivalent focal length would be approximately 216mm (you must multiply the focal length by 1.6 to determine the 35mm equivalent focal length on the Digital Rebel). If you use more some, the camera shake problem will be worse.

So, the fastest shutter speed possible in this lighting with the lens you appear to have (while still getting proper exposure), even at the highest ISO speed supported by the camera (ISO 1600), your shutter speeds will be well below the 1/focal length rule of thumb to prevent blur from camera shake if using much zoom.

This is why a lens with a constant f/2.8 aperture throughout the focal range is needed for night sports. You can use shutter speeds 4 times as fast at f/2.8 compared to f/5.6 for any given lighting level and ISO speed.

If you're on a budget, I'd look at theSigma 70-200mm f/2.8 EX APO IF HSM:

http://www.bhphotovideo.com/bnh/cont...317&is=USA

If you're not on a budget, look at the Canon 70-200mm f/2.8L IS lens. It's stabilized to help prevent blur from camera shake, so it would be useful in a greater variety of conditions:

http://www.bhphotovideo.com/bnh/cont...444&is=USA

In the meantime, try to figure out what's wrong with your camera's autoexposure. Answer my questions above to see if we can narrow it down (what lens were you using, did it occur only with flash forced on, did it occur with more than one lens, etc.). Try resetting it to factory defaults; and also see if the problem occurs in Aperture Priority (Av) mode -- selecting the largest available aperture yourself (smallest f/stop number).

If it still underexposes photos in all modes,and the problem ends up being the lens or the camera, and you don't have time to swap them out with your vendor; try going full manual exposure with it to see what that does.

Set the aperture to the largest available aperture (represented by the smallest f/stop number) for tonights game, then go ISO 800, and see what shutter speeds the camera thinks it needs for proper exposure pointing to the field area. You'll see an EV scale that will tell you if your settings are underexposing or overexposing the scene -- based on what the camera's metering thinks. You'll need to adjust frequently (especially prior to sundown) for different areas of the field due to lighting differences. Once the sun goes down, you'll probably want to go to ISO 1600 to keep blur from camera shake toa minimum.

Hopefully, at least the metering part works (but that could even be the problem -- in which case it won't be useful for manual exposure anyway). So, you'd have to "fudge it" --- guessing at proper exposure. ISO 1600 at 1/125 second and f/5.6after sundown should get you close. Shoot in RAW if you have the space to give you more exposure latitude later. You won't be able to rely on the LCD during playback, as the images may be darker than they appear in the LCD.

Practice holding the camera steady, and controlling your breathing (as if you're target practicing with a firearm), thenslowly squeezing the shutter button to try and keep motion blur from camera shake to a minimum.

If you can't get it working any other way, and don't have time to swap it out, you'll need to know ahead of time if the metering works or not.

You may also want topost some unmodified test photos (not touched by PSCS) somewhere so we can see all of the EXIF information to see if their is any clue as to what could be wrong. If you don't have a place to post them, open a free trial account at http://www.pbase.com and post a link to the album. You'll be limited to 10mb of storage with a trial account, but that should be enough for a couple of samples.

You'll get lots of noise in your photos trying to shoot at higher ISO speeds, so you'll need to clean up the photos later. Here are some tools:

http://www.imagenomic.com/ (this one is free)

http://www.neatimage.com

http://www.picturecode.com

P.S. -- Again, I don't own your camera, so I'm only speculating as to what may be wrong, based on my limited knowledge. Something is causing the camera's autoexposure not to work properly -- underexposing your photos. Try my suggestions above first (especially themenu option to clear all settings) -- then you may want to check on the Canon SLR forum, too.



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Old Sep 3, 2004, 1:35 PM   #10
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I vote that Jim change his last name to "Google" ;-)
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