More Night Flash Football

At full power the canon 580 EX will have a flash duration of about 1/800 second (1.2 millisecond). At lower power settings, the duration will get shorter and shorter. (This is the opposite of strobes like Alien Bees.)

Canon provides the flash duration for full power. If you google 'canon 580ex flash duration' you will see several authors with estimates of the times for durations at lower power. The point is that flash occurs fast enough to stop the action at full power and gets quicker with lower power.

so as I reduce the power from full down the ability to stop action gets quicker?

Matthew - You are partially correct. As you reduce power, the flash duration gets shorter and shorter. However, as the power of your flash goes down, not only does your range go down (reducing the distance at which you can "freeze" action), but also in reducing flash power, your flash level gets closer and closer to ambient light levels, so you approach violating the rule for stopping action: "keep flash/strobes at least one stop over ambient", and also you increase your likelihood of getting ghosting.

I was experimenting last night shooting some tree leaves from about the same distance as the players might be, and the same time of day and did some manual power shots and got some decent results, they were not moving, but still helped with getting correct exposed flash image

Matthew,

You bring up an interesting point on shooting the flash in manual mode. I know Dennis likes to shoot with the flash in manual and I am currious as to why?

Dennis, would you mind explaining the advantages and disadvantages to shooting with the flash in manual? I presume you use the hash marks on the field as a distance reference point and adjust your flash power based on that distance. If a player ends up being closer/father away than what you had anticipated, do you just correct the exposure in PP?

just the thread i was looking for, i was trying shoot some photos of rugby players on a flood lit pitch. they were either so dark i (i assume in focus) or so bright (but blurred) with ghosting of the players. I didnt use a flash as was shooting in TV mode. i didnt try manual mode either. I was using a 40d with stanard kit lens.

Matts,

ETTL is too easily fooled, which can end up with an improperly exposed shot and/or ghosting from lower than required flash power level. Like many things automatic, ETTL is a one-size-fits-all kinda thing, and I just don't trust it.

Sometime I'll do this, but more often I'll roll the flash power up or down as the distance to the subject changes.

And, no, I don't use any hash mark. I kinda use my gut/eye to gauge it, but like I've said before, there is very little "normal" or "predictable" about shooting night football. Every game is part intuition, part experience, part skill, part technology and not a small amount of luck.

Merciez wrote in post #6259907
Matthew,

You bring up an interesting point on shooting the flash in manual mode. I know Dennis likes to shoot with the flash in manual and I am currious as to why?

Dennis, would you mind explaining the advantages and disadvantages to shooting with the flash in manual? I presume you use the hash marks on the field as a distance reference point and adjust your flash power based on that distance. If a player ends up being closer/father away than what you had anticipated, do you just correct the exposure in PP?

I would be curious to hear what he has used in the past for power settings based on hash marks, I know of others that do that but never explained how.

dmwierz wrote in post #6259974
Matts,

ETTL is too easily fooled, which can end up with an improperly exposed shot and/or ghosting from lower than required flash power level. Like many things automatic, ETTL is a one-size-fits-all kinda thing, and I just don't trust it.


Sometime I'll do this, but more often I'll roll the flash power up or down as the distance to the subject changes.

And, no, I don't use any hash mark. I kinda use my gut/eye to gauge it, but like I've said before, there is very little "normal" or "predictable" about shooting night football. Every game is part intuition, part experience, part skill, part technology and not a small amount of luck.

Thanks Dennis,

I could see adjusting the flash power before the play starts. The situation which I obviously did not explain very well is during the play. Assuming you setup your flash power based on an area of the field, but now the running back breaks free for a great shot but he is 15 yards closer than you had initially planned, I can't see you adjusting the flash power in the middle of the play??? This is the situation where I would see needing to adjust the exosure in PP.

What would be nice is the ability to adjust flash power from the camera when the flash is in manual (not via the menu screens but a faster adjustment).

I guess one could use the ISO or aperature to adjust exposure vice flash power when shooting with the flash in manual. Assume you are 25 yards downfield shooting back up field such that the offence is facing you. Setup for ISO 800, f4.0 and SS of 250. Set your flash power for a proper exposure. If the running back/quarter back breaks free, as he gets closer, you can reduce the ISO to 640 or decrease your aperature to F5.0 to offset the reduced distance. Seem reasonable?

Matt,

I guess you missed the part of my post where I said:

What I mean by this is I actually change the flash output based on how the play is developing. This isn't easy, but it's not that hard. And no, before anyone asks, I don't have any way of knowing quantitatively how much to change it. Each click is one fraction of full power, and all I'm hoping to do is a) get enough additional flash power to grab the play farther out than where I was set up or b) dial down the flash so I don't blow out the play that is coming at me.

Hear me now when I say: there are no secrets here, and don't expect a cookbook or recipe. More than anything I have ever done in sports photography, night flashed football is about the 3 "F's": Feel, Feedback and Flash. You feel how much flash you need based upon how things have gone so far in the game; you get feedback from your histogram to affirm or contradict your feelings; then you employ appropriate flash power to either keep going how you were if things are working, or change the flash if needed.

This is the photographic equivalent of Plan Do Check Act (for all you Engineers out there).

All you're gonna do with changing the shutter speed (or the aperture or even the ISO) is change the exposure for ambient. You're not really going to be affecting the flash exposure. I know this is counter-intuitive, but this is how it works. The flash is SO bright and SO short, you can almost change the camera's setting to anything and have the results be the same up to the point where you're letting ambient be close to flash power.

I think I said it here, or maybe on another board: one of these upcoming games I'm gonna put my shutter at something like 1/125s for one quarter to just show how the results are virtually the same as those at 1/250s (providing I have enough delta between ambient and flash - this is where darker fields are actually better).

dmwierz wrote in post #6254274
Make sense?

the explanation or your use of a jumping gnome as an example? as always, I'm amazed by you Dennis.

As for the use of flash, I have nothing to add other than to suggest any naysayers do heed Dennis; advice. He's got this thing down and it's not that often you find shooters of his caliber that are actually willing to share and help.

is there a way to tell if a shot in infocus on camera besides looking at the screen, as I find a lot when I chimp I see shots that look clear, but then get them into PP and see that infact they are the opposite and OOF

starting to realize the best way for me to get this is shoot, post for feed back and then shoot again and try and correct what I did wrong before, like they say practice make perfect

mestes wrote in post #6261709
is there a way to tell if a shot in infocus on camera besides looking at the screen, as I find a lot when I chimp I see shots that look clear, but then get them into PP and see that infact they are the opposite and OOF

starting to realize the best way for me to get this is shoot, post for feed back and then shoot again and try and correct what I did wrong before, like they say practice make perfect

there's no real way other than getting them on the machine. you are 100% correct on the practice thing though. keeping that little red box right on your moving target as you pan and making sure you got steady hands isn't always the easiest thing to do and at longer distances, even the slightest twitch can throw you off focus.

yea I need to invest in a decent monopod but that might be a while

mestes wrote in post #6264417
yea I need to invest in a decent monopod but that might be a while

don't sweat the monopod. it can help but to be honest, I'd rather handhold the 70-200. Its not a big lens and you ae just so much more flexible in your shooting when you aren't tethered to a stick. others may disagree but I'd rather shoot without one if at all possible.

another option (that I have no experience with) is this thing...http://www.bhphotovide​o.com …_2702_Chestpod_​Magic.html
I've seen quite a few on the sidelines lately and I assume its a workable option.