Faster Shutter Speeds with 10D and 550EX

[dpanicc1]

Hi,

I am still trying to nail down some details on this great camera--I guess this question pertains to all cameras.

I normally shoot with the above combo manually with the shutter set to 60 and the aperature to what ever. X-sync goes to 1/250 on the 10D. Now, is there any advantage for inside flash photography to use a faster shutter speeds given the short duration of the flash?

Thanks,
Dan

[drisley]

I believe that if you increase the shutter speed, you will end up with you main subject being well lit (by the flash) and the background being darker.

If you use a slower shutter speed, you will have more even illumination across the board.

BTW, if you set the flash to hi-speed sync, you can get faster shutter speeds than 1/250s

[dpanicc1]

Okay, but the faster shutter speed does nothing to freeze the subject because the subject is "frozen" by the flash, correct? In other words I won't get a "sharper" grandchild's photograph is I use 1/250 instead of 1/60, right?

I understand E-TTL uses the aperature and shutter to adjust exposure for ambient lighting and the flash intensity is based on the active focus point (primarily); the E-TTL system sends out a pre-flash to set flash output intensity. I wrote this is confirm my understanding of the system so if it's not right feel free to correct me.

Thanks again....

[PacAce]

Okay, but the faster shutter speed does nothing to freeze the subject because the subject is "frozen" by the flash, correct? In other words I won't get a "sharper" grandchild's photograph is I use 1/250 instead of 1/60, right?


You are absolutely right. However, as drisley stated in his post, the shutter speed does make a different in how the background comes out. In other words, the slower may show the grandmother in the background lovingly looking at the her grandchild while the higher shutter speed may show a darkened background where the details can hardly be made out. You may prefer one over the other but at least you know you have a choice. :)

[DaveG]

Okay, but the faster shutter speed does nothing to freeze the subject because the subject is "frozen" by the flash, correct? In other words I won't get a "sharper" grandchild's photograph is I use 1/250 instead of 1/60, right?


You are absolutely right. However, as drisley stated in his post, the shutter speed does make a different in how the background comes out. In other words, the slower may show the grandmother in the background lovingly looking at the her grandchild while the higher shutter speed may show a darkened background where the details can hardly be made out. You may prefer one over the other but at least you know you have a choice. :)

Well you choice of shutterspeeds with flash CAN affect the sharpness depending on what you are doing. If I was shooting a basketball game with a 10D (whose flash synch is 1/200, not 1/250 by the way) and I wanted a flash exposure of say 1/60 @ f5.6. If the ambient light in the room is 1/60 @ f2 then it's three stops less than what the camera is set up for. If I use no flash then I'll get a horrible, pretty much unprintable capture. But I do get something. So when I use the flash that will freeze the action but I also have this secondary ambient exposure too. This is what causes ghosting. You've kind of done a multiple exposure at one time. You have the sharp flash exposure and the blurred ambient light one too.

In any case with flash, you do have to be careful about how close you are to the ambient light exposure in the room. Now if the subjects are motionless this caution is moot. I often will use this techique (from a tripod) at a wedding. I'll have the bride and groom on the alter steps, posed for a formal portrait. The ambient light might be 1/8 @ f5.6. I'll set the shutterspeed and aperture to that setting and the flash's output set to 5.6 as well. This brightens up the background and the flash fills in the racoon eyes. But I always tell the B&G that the exposure is going to be slightly longer than the flash pop and that they shouldn't move after the shot.

I do get the "second" ghost image but it's so closely registered with the flash exposure that you can't see it.

I won't even try this technique for group shots. Aunt Gertrude or Uncle Clarence JUST won't get it and will immediately turn at the flash pop. "Oh, did I move?" giggle giggle. Stupid cow.

So if your grand kids are romping about the room at full speed you might want to forget about ambient light fill and use 1/200 @ f8 to nail their movements down.

[dpanicc1]

Great! Thanks everyone for the great responses. I appreciate everyone's help. I learned something here today; that means it's a good day. Regards, Dan. :D