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View Full Version : Shots from Fridays Game with 300 2.8


acidburn_85
Sep-03-2008, 04:18 AM
This was my first attempt at football action with my new 300 2.8 IS. C&C Welcomed...This is also my second attempt at using a prime for sports.

http://farm4.static.flickr.com/3199/2815983298_6c7a408721_o.jpg

http://farm4.static.flickr.com/3145/2815977676_62a00687c4_o.jpg

http://farm4.static.flickr.com/3178/2815977568_2d761fb789_o.jpg

GP Images
Sep-03-2008, 07:37 AM
Were these hand held? Colors are great but they are not sharp. Not sure if it's camera shake or motion blur, what were the camera settings?

acidburn_85
Sep-03-2008, 07:43 AM
No they were on a monopod it is motion blur they were shot at 1/250@2.8 ISO 1600

Were these hand held? Colors are great but they are not sharp. Not sure if it's camera shake or motion blur, what were the camera settings?

jjvfx
Sep-03-2008, 07:52 AM
I mainly shoot sports and have been to some of the worst lighting America has to offer. I wouldn't go under 1/320 and maybe try bringing the ISO up to 3200.

I bet you could do 1/400 at 2.8 with ISO 3200

Jordan

johng
Sep-03-2008, 09:07 AM
OK - looks like you're already using flash. But you're not stopping the action so you're exposure is too close to ambient. Drop your ISO to 800 and you should get better freeze of the action.

mercphoto
Sep-04-2008, 08:16 AM
OK - looks like you're already using flash. But you're not stopping the action so you're exposure is too close to ambient. Drop your ISO to 800 and you should get better freeze of the action.
At 1/250 a second I can't remember if you have to go to high-speed-sync on the flash or not. You should NOT be using high-speed sync as this will not help you freeze the action. John has a good point -- drop the ambient exposure and let the flash fire harder.

rockcanyonphotos
Sep-04-2008, 09:42 AM
At 1/250 a second I can't remember if you have to go to high-speed-sync on the flash or not. You should NOT be using high-speed sync as this will not help you freeze the action. John has a good point -- drop the ambient exposure and let the flash fire harder.

I am curious... why do you NOT want to use high-speed sync? I have always used it... but then I will never admit to being real versed in the correct use of flash.... so I really would like to know the reasoning behind it, I just always assumed you wanted it for high shutter-speeds.

thanks, Kevin

johng
Sep-04-2008, 09:50 AM
I am curious... why do you NOT want to use high-speed sync? I have always used it... but then I will never admit to being real versed in the correct use of flash.... so I really would like to know the reasoning behind it, I just always assumed you wanted it for high shutter-speeds.

thanks, Kevin

It drastically reduces the reach of the flash.

mercphoto
Sep-04-2008, 10:43 AM
I am curious... why do you NOT want to use high-speed sync? I have always used it... but then I will never admit to being real versed in the correct use of flash.... so I really would like to know the reasoning behind it, I just always assumed you wanted it for high shutter-speeds.

thanks, Kevin

Well, you do need hi-speed synch for high shutter speeds. However, in your case, in lighting that dim, you never will get high shutter speeds.

Fundamental question: 1) do you know how a shutter works? 2) do you know how the flash fires when not in high speed sync? 3) do you know why this limits the max shutter speed when a flash is used? And 4) do you know why the high-speed synch feature gets around this limitation?

To be as brief as possible about the answers to the above, when the shutter opens it does so in a manner similar to barn doors. This isn't entirely accurate but it gets the point across. Two doors, one in front of the other, close off the barn. One door is completely to the side of the door, and the other door completely obscures the door. Now its time to expose the shutter, to open the barn doors. We do this by sliding the door obscuring the barn over to the opposite side. This starts exposing a little, then a bit more, then a lot more of the barn opening. Eventually the entire door is opened. Then we start to close the opposite door, obscuring a little, then more, then finally fully closing the barn. Get it?

The longer we want the shutter open, the longer we delay from the time we move the first door to the time we start to move the second door. For faster shutter speeds we start closing the second door sooner after opening the first door. For long shutter speeds the first door will be completely open for some time before the second door even starts to close. Still with me?

Now, we can only move these doors so rapidly. At some point there comes a shutter speed at which at the moment the first door is fully open we start closing the second door. This happens to be your flash sync speed.

Think of it this way, that happens to be the fastest shutter speed that also has the entire sensor/film exposes completely with both doors open.

Why does this matter with a flash? Because a flash is normally an extremely brief burst of light. And we can fire the flash at this precise moment in time and expose the entire sensor.

Now, what happens when we try to go faster than this? To get a faster shutter speed, lets say a shutter twice as fast, we can't move the doors any faster, so what we do is start closing the second door before the first door is completely open. For a shutter twice as fast we'll start closing the second door when the first door is half-way open. Notice what happens now is there is no point in time when the entire sensor is completely exposed -- there is a moving window half the sensor's width exposed at any time. So if we fire that extremely brief burst of light we'll only illuminate half the sensor. Not good!

So when we're in high-speed synch mode what happens is the flash changes how it bursts its light. Instead of an extremely brief burst of very bright light, it does a longer burst of less intense light. The overall light output works out the same. But the burst is long enough that it will illumintate the entire sensor by keeping the flash lit as that moving window travels across the barn door.

What you are doing, by having your flash set to hi-speed synch mode, is always having a long burst of light, rather than a fast burst of light. And that fast burst of light will be your friend, ACTING LIKE A STROBE LIGHT IN A DISCO.

So, keep your flash off high speed synch, keep your shutter at or below the max sync speed of your camera, set ambient exposure a stop or two underexposed, and let that extremely brief burst of flash light stop your action. It will effectively raise your shutter speed, but this only works if the flash is your primary source of light (this is why you want the ambient underexposed a bit).

Shot at 1/200 a second with this method. Normally a shutter that long would have tons of wheel blur. Look how frozen the spokes are:
http://mercphoto.smugmug.com/photos/86425594_RjmgZ-M.jpg

bobcool
Sep-04-2008, 02:23 PM
To wrap up what Bill said:

Put your camera on 800 ISO, 1/250th (or whatever is your max sync speed)
Adjust aperture(if 800 ISO isn't enough to bring exposure down to -1 from ambient) until you get around one stop under ambient
Disable high-speed sync
Put flash on manual mode
Set flash to 1/4 power (this is a starting point)
Shoot some test shots, adjust flash power as necessaryWhen you use this method, the duration of the flash becomes your effective shutter speed. Here's an example of what my shutter speed becomes with my SB-600 flash:

1/900 sec. at M1/1 (full) output
1/1600 sec. at M1/2 output
1/3400 sec. at M1/4 output
1/6600 sec. at M1/8 output
1/11100 sec. at M1/16 output
1/20000 sec. at M1/32 output
1/25000 sec. at M1/64 output

Even at full power you're effectively getting 1/900th "shutter speed." More than enough to freeze the action, don't you think?

rockcanyonphotos
Sep-04-2008, 09:33 PM
HOLY CRAP!! That is probably the clearest and most concise explanation I have ever heard. I wish I had asked this question a few years ago. As I think back over the last few years of shooting high school football, in the context of this information....it makes a lot of sense, and also explains a lot of my frustrations.

Bob, Bill, thanks for taking the time to explain this is such great detail.

regards, Kevin

BCSPhotoguy
Sep-05-2008, 06:25 AM
To wrap up what Bill said:

Put your camera on 800 ISO, 1/250th (or whatever is your max sync speed)
Adjust apeture(if 800 ISO isn't enough to bring exposure down to -1 from ambient) until you get around one stop under ambient
Disable high-speed sync
Put flash on manual mode
Set flash to 1/4 power (this is a starting point)
Shoot some test shots, adjust flash power as necessaryWhen you use this method, the duration of the flash becomes your effective shutter speed. Here's an example of what my shutter speed becomes with my SB-600 flash:

1/900 sec. at M1/1 (full) output
1/1600 sec. at M1/2 output
1/3400 sec. at M1/4 output
1/6600 sec. at M1/8 output
1/11100 sec. at M1/16 output
1/20000 sec. at M1/32 output
1/25000 sec. at M1/64 output

Even at full power you're effectively getting 1/900th "shutter speed." More than enough to freeze the action, don't you think?

That is awesome information! I am always nervous of asking "those questions" about flash useage - so seeing it simply put enables me to go and try it myself! Thanks for the free education!! If there any other SB-600 tutorials availble, I may be interested!!! :rofl

donek
Sep-05-2008, 12:04 PM
Well, you do need hi-speed synch for high shutter speeds. However, in your case, in lighting that dim, you never will get high shutter speeds.

Fundamental question: 1) do you know how a shutter works? 2) do you know how the flash fires when not in high speed sync? 3) do you know why this limits the max shutter speed when a flash is used? And 4) do you know why the high-speed synch feature gets around this limitation?

To be as brief as possible about the answers to the above, when the shutter opens it does so in a manner similar to barn doors. This isn't entirely accurate but it gets the point across. Two doors, one in front of the other, close off the barn. One door is completely to the side of the door, and the other door completely obscures the door. Now its time to expose the shutter, to open the barn doors. We do this by sliding the door obscuring the barn over to the opposite side. This starts exposing a little, then a bit more, then a lot more of the barn opening. Eventually the entire door is opened. Then we start to close the opposite door, obscuring a little, then more, then finally fully closing the barn. Get it?

The longer we want the shutter open, the longer we delay from the time we move the first door to the time we start to move the second door. For faster shutter speeds we start closing the second door sooner after opening the first door. For long shutter speeds the first door will be completely open for some time before the second door even starts to close. Still with me?

Now, we can only move these doors so rapidly. At some point there comes a shutter speed at which at the moment the first door is fully open we start closing the second door. This happens to be your flash sync speed.

Think of it this way, that happens to be the fastest shutter speed that also has the entire sensor/film exposes completely with both doors open.

Why does this matter with a flash? Because a flash is normally an extremely brief burst of light. And we can fire the flash at this precise moment in time and expose the entire sensor.

Now, what happens when we try to go faster than this? To get a faster shutter speed, lets say a shutter twice as fast, we can't move the doors any faster, so what we do is start closing the second door before the first door is completely open. For a shutter twice as fast we'll start closing the second door when the first door is half-way open. Notice what happens now is there is no point in time when the entire sensor is completely exposed -- there is a moving window half the sensor's width exposed at any time. So if we fire that extremely brief burst of light we'll only illuminate half the sensor. Not good!

So when we're in high-speed synch mode what happens is the flash changes how it bursts its light. Instead of an extremely brief burst of very bright light, it does a longer burst of less intense light. The overall light output works out the same. But the burst is long enough that it will illumintate the entire sensor by keeping the flash lit as that moving window travels across the barn door.

What you are doing, by having your flash set to hi-speed synch mode, is always having a long burst of light, rather than a fast burst of light. And that fast burst of light will be your friend, ACTING LIKE A STROBE LIGHT IN A DISCO.

So, keep your flash off high speed synch, keep your shutter at or below the max sync speed of your camera, set ambient exposure a stop or two underexposed, and let that extremely brief burst of flash light stop your action. It will effectively raise your shutter speed, but this only works if the flash is your primary source of light (this is why you want the ambient underexposed a bit).




Fantastic explanation. Thanks so much.