Well you have my curiosity piqued now... Maybe I am becoming complacent, I always like to try new things. Maybe +2-3 stops and a slower shutter speed is what you are suggesting? Give me an example to try this evening. I'll be shooting a 1dIII 400/2.8 and 2 580exII's to play with. Don't want to try HSS this time but more what dmwierz is suggesting. Mostly I found that i could shoot at a high rate on 1/8-1/16 manual and the uniforms would "pop" a little and I'd get some light under the visor and it still looked natural. Definitely open to alternative solutions.
pdxammo wrote:
...but one must truly grasp the relationships of all the factors that come into play...
I haven't read every post, so at the risk of saying what has already been said and what is obvious to probably most on here...
The controls available for adjusting 1) ambient exposure, 2) flash exposure, and 3) the ambient-flash delta, differ depending on whether you're shooting Manual Flash or TTL Flash.
So, generally...
If shooting Manual Flash -
Ambient exposure is controlled by aperture (Ap), shutter speed (SS), and ISO.
Flash exposure is controlled by Ap, ISO, distance to subject (D) and flash power (P).
Meaning, in this case, if you want to play with your ambient-flash delta, notice one independent control available to do this is SS. If you adjust Ap or ISO, then you change both ambient and flash exposure. If your subject moves closer to you and you want to maintain the same flash exposure, but not affect ambient exposure, then reduce P.
If shooting TTL Flash -
Ambient exposure is still controlled by Ap, SS and ISO.
Flash exposure is controlled, automatically, so to speak, by P.
thanks dennis,
if this is true: Meaning, in this case, if you want to play with your ambient-flash delta, notice one independent control available to do this is SS. If you adjust Ap or ISO, then you change both ambient and flash exposure. If your subject moves closer to you and you want to maintain the same flash exposure, but not affect ambient exposure, then reduce P.
its going to be a little difficult to reach all the way down, turn on the light on the back of the flash so that i can see what i'm doing, then make the adjustments to lower the power all in a blink of an eye. It sure makes ETTL alot more attractive. It certainly makes sense what you said about the effects on ambient by changing iso or aperture, even though i've had a few suggestions to just use my finger to rotate the dial to change aperture as the action comes closer. All i can do is experiment for myself and see what happens. I love all of the input, and i can say for a fact that i have a better idea of what to try now.
teppy1 wrote:
its going to be a little difficult to reach all the way down, turn on the light on the back of the flash so that i can see what i'm doing, then make the adjustments to lower the power all in a blink of an eye.
I couldn't agree more
I believe I recall correctly that Matthew (msauk) adjusts Ap as the athlete moves closer or farther away and I'm guessing he's shooting Manual Flash. If that is the case, then I suppose his other controls are set such that his ambient-flash delta is appropriate. Whatever the heck he does, it produces some great shots, IMO. Search his name on here.
you are exactly right. he is one that i have communicated with about this specifically. he does use a manual flash. he suggested to me to use manual and keep my fstop from 2.8 for away action, and adjust up to around f4 as the the action gets closer.
teppy - IS has no real function when shooting sports. It's intended for use to combat camera shake, not subject movement, when your shutter speed is slower than 1/(focal length).
Since you're using the flash to stop action, and the flash duration is 1/800s or faster (at least for a Canon 580EX), IS won't provide any benefit, and in fact, it may perceptibly slow AF.
what about when handholding? for sure it helps for camera shake there? i've been handholding until tonight. i will my monopod so that i can mount my flash. the monopod will be moving i'm sure because i don't think i will keep that perfectly still either.
If your shutter speeds are > 1/(focal length), then IS won't be any advantage. Your shutter speed (or flash duration) is faster than any impact you might encounter from minor camera movement.
If you are handholding, shooting with available light, and your shutter speeds are lower than 1/(focal length), then you're probably only shooting players standing around. THEN, maybe you could use IS mode 1.
There is one exception to this rule, and that's when horizontal panning with high-speed subjects like cars, horses, etc., where mode 2 can help.
The flash strobe is much faster than the 1/250" SS you'll be using. So don't worry about IS. Turn it off.
Even if you're not using flash, with shutter speeds between 1/500" - 1/1000" (which is the range you should maintain for football), handheld shake won't be as much of a factor as it usually is. If you were doing handheld shots at 1/60" - 1/250", yes IS is valuable.
A reasonably steady hand is still preferred, but the IS gyro takes a while to spin up (especially on older lenses like the 100-400 and 70-200/2.8... the 70-200/4L IS is newer and a bit faster), so I usually turn it off for sports.
There are plenty of examples where you can get bizarre blurring if you take a shot before the IS gyro isn't up to speed.
