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Old Aug 3, 2006, 5:35 PM   #1
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I saw some photos in AV mode of fast moving military jets. I thought you have to use TV mode for fast moving objects. I'm wrong or not.
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Old Aug 3, 2006, 7:05 PM   #2
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HAVE to? No. Easier, perhaps. If you are steady enough to pan with your moving image you can often get good, sharpshots. I do it often at airshows.
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Old Aug 4, 2006, 12:00 AM   #3
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I would completely disagree that it is easier to stop motion of jets with Tv.

I would say that is it easier to stop motion of jets with Tv but get really bad exposure.

But I'm bias 'cause I always shoot in Av.

All Av says is that you set the aperture and it picks the shutter speed. If you pick the largest aperture your lens allows (lowest f-stop) then you'll get the highest shutter speed for the available light. Just pick center weight average metering mode or spot if you have it, maybe put in a stop or two of exposure compensation to compensate for the bright sky and you're off to get flight shots with a proper exposure.

And don't forget to leverage the histogram and LCD to make sure you've got the correct exposure (I fix that with exposure comp.) You'd hate to have a sharp black blob with a proper exposed sky.

The trick with Tv is that you could dial in a good fast shutter speed, but what happens if even with at largest aperture it isn't enough light for the correct exposure? The camera can't adjust any more so it just misexposes.

Maybe I'm missing something 'cause I never use Tv... but it always seemed like a risk to me. You can't pick an incorrect aperture (it can always adjust the shutter speed so the picture will be properly exposed. Blurry due to too low a shutter, but properly exposed.) I can compensate for blur (use a tripod or good panning technique) but I can only fix so much under exposure with photoshop before the image is unusable.

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Old Aug 4, 2006, 10:29 AM   #4
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I'm with Eric for the most part. I shoot Av 90% of the time and avoid Tv for exactly the reasons Eric pointed out PLUS I shoot sports so I like a shallow depth of field most of the time.

But, I want to emphasize something Eric mentioned - you have to understand how your camera does it's metering. In 99% of action shots of any type - planes, birds, people, whatever - you want to expose for your subject and not the background. It gets even trickier when your subject has too much dynamic range to caputre (stark whites and deep blacks).

Worst case is overexposed subject and normal exposed background - if you've blown the highlights the shot is probably a throw-away.

Next is underexposing your subject and properly exposing background. How bad this is depends on how much you've underexposed by - if it's not bad you can recover the detail. But in some cases you've underexposed too much and too much detail is lost. In my experience this is the more common scenario - perfectly blue sky and black "thing" flying, running whatever.

I would rather blow highlights in a background and have a properly exposed subject. That's where either shooting manual mode is popular among a lot of action photogs - assuming lighting is fairly constant. Me, I prefer to do what Eric does - use EC to make sure it's my subject being exposed properly.

If you have spot metering this can be a great benefit in these situations. If not, framing as tight as possible so your subject fills more of the frame will allow a center-weighted metering to do a better job. But for birds / planes that might be too far away - EC is your friend.
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Old Aug 6, 2006, 12:26 AM   #5
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What are some tips using the AV mode indoors? I have a Canon Rebel XT with a Canon 550EX speedlight.
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Old Aug 6, 2006, 6:49 AM   #6
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Av is probably the worst mode indoor with the 550EX...
The camera will try to do a fill with your fixed shutter and pick the slowest shutter speed for ambient light in which case the subject will be blurry if it moves...

-> Manual mode is probably the best because you'll get to pick the shutter and aperture, and the flash will do the rest automatically by balancing its output to match! This scale in your viewfinder will be your best friend: -3..-2..-1..v..+1..+2..+3. Center is ambient light, and the more the scale is tilting to the left the more flash you'll have...
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Old Aug 6, 2006, 10:18 AM   #7
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This is a great thread. I have been using multimeter mode most of the time and find underexposure of subject to be a problem. I think I started doing this because when using my 580 EX flash, Canon recommends that mode for use in TTL. But then I pretty much left it there and forgot about changing it for shooting without flash except for the occasional "spot" metering that I do...

I do a lot of shooting of my dogs in action and have been using Tv for that. I generally dial in the fastest speed that I can to give me the widest aperture and try to stay at ISO 400 or under. I will have to try Av, and maybe even using NHL's technique of using the flash to stop the action in manual mode. I never really thought much about that since most of the time there is very bright sunlight in those outdoor shots. The dogs are constantly moving and not in a way that is amenable to panning, so I have been trying to rely on very fast shutter speeds ie 1/1000 or above. That usually leave me at 2.8 and a DOF that is really thinner than I want... But if I use the flash, I think multimeter would be the right choice...??? I'm not sure how the exposure would be affected using center weight and TTL2 flash. I have also been uping the FEC about 1 stop pretty ubiquitously to adjust for Canon's tendency to underexpose its flash metering.

H
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Old Aug 6, 2006, 10:22 AM   #8
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NHL that what I wanted to here about the AV mode because boy, I was struggling with this mode indoors. I tried everything I could. Maybe the pros have no problem but I did.
NHL everytime I switch to manual mode my scale is always way over to the left is that normal? Is this scale for the photo or the flash in manual mode? I hardly ever get sunlight in the house. Living in Alaska, we don't get much normal sunlight coming indoors. This was bad for weather. My manual is worthless. Thanks.:lol:
NHL wrote:
Quote:
Av is probably the worst mode indoor with the 550EX...
The camera will try to do a fill with your fixed shutter and pick the slowest shutter speed for ambient light in which case the subject will be blurry if it moves...

-> Manual mode is probably the best because you'll get to pick the shutter and aperture, and the flash will do the rest automatically by balancing its output to match! This scale in your viewfinder will be your best friend: -3..-2..-1..v..+1..+2..+3. Center is ambient light, and the more the scale is tilting to the left the more flash you'll have...
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Old Aug 6, 2006, 10:43 AM   #9
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NHL wrote
What mode should I put Canon 550EX in for manual mode for indoors.
Quote:
Av is probably the worst mode indoor with the 550EX...
The camera will try to do a fill with your fixed shutter and pick the slowest shutter speed for ambient light in which case the subject will be blurry if it moves...

-> Manual mode is probably the best because you'll get to pick the shutter and aperture, and the flash will do the rest automatically by balancing its output to match! This scale in your viewfinder will be your best friend: -3..-2..-1..v..+1..+2..+3. Center is ambient light, and the more the scale is tilting to the left the more flash you'll have...
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Old Aug 6, 2006, 11:59 AM   #10
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Just set your camera to manual mode and the camera will communicate to the flash. Just turn it on... You can set flash exposure compensation with the camera or the flash but the exposure result will be the same. ( I think...) You make adjustment to exposure by changing the speed, aperture or ISO which will move your camera meter as NHL described above and will affect the power level of the flash to expose properly, so long as you are to the left or in the middle of the meter range. The more to the left of the middle, the darker the background will be since the flash metering will properly expose the subject. The camera meter is telling you how the background will be exposed. You just have to also be careful that the max distance to your subject is in range of the power for your flash and should be noted on the flash's LCD screen. If you are too far away, your subject will be dark too..

I have a 580 EX and Canon recommends multimeter mode to correctly use TTL2 and flash. I am not sure, but I think it is the same for the 550 EX...

As NHL said, Av mode and flash don't generally mix well, especially in low light because of the very slow shutter speeds.

Spend some time reading this web site.

http://photonotes.org/articles/eos-flash/

It is very well written and a great place to really learn flash photography. I read it about a year ago and will probably re-read it to refresh my memory. I find flash photography to be generally more complicated even with all the automation and meters built in!

H

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What mode should I put Canon 550EX in for manual mode for indoors.
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