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Thread: Bird Photography - Flash Dance - How to prevent it ??

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    Bird Photography - Flash Dance - How to prevent it ??

    Not sure that this really belongs in this forum but it is a Flash question more than strobist ??.
    I hope Tony, Rich, Col etc will find it here.

    On Saturday afternoon I spent some time down by a creek at Blackdown Tableland where there were quite a few species of small birds, Honey-Eaters, Thornbills, Fairy Wrens, Scrub Wrens etc, having their afternoon drink and bath.
    I was relatively close, maybe 20 mtrs, once I had worked out their routine and found an appropriate bush to perch behind.

    My problem is that a large quantity of the shots have got the bird "Flash Dancing"

    40D, 580 EXII, 120-400 Sigma
    ISO 400/800 1/250 f 8 / f6.3, -2/3 FEV

    I tried Highspeed sync at 1/250, I tried dropping speed back to 1/200 (std sync speed), I tried first curtain syn and second curtain sync ??........

    My question is - How to I prevent or minimise this behavior or is it just a fact of life ???
    Smoke Alarms Save Lives, Install One Today
    I shoot Canon
    Cheers, Mark


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    What behavior are you talking about, what went wrong?

    Without knowing the exact details, here are some pointers:
    - what mode did you have your camera on (M, Tv, Av?)
    - How much ambient light was there? If there's plenty of light available ("saturday afternoon", probably a lot of light?), chances are your flash would not have added much. I assume ambient light ≈ 12 EV (typical scene, heavy overcast). Without flash, 100 ISO would've given f/5.6 @ 1/125 second, at 400 ISO f/11 at 1/125 or f/8 at 1/250.

    Let's do the calculations:
    - GN 580EX = 58 at 100 ISO => at 400 ISO GN = 116
    - At 20 meters, you'ld need aperture set at 116 / 20 = f/5.8 (in reality: f/5.6)
    - With FEV = -2/3, you have maximized the output of the flash

    Ergo, you've most probably balanced the flash against the ambient light which makes things very, very tricky. What was the effect you where after?
    Ciao, Joost

    All feedback is highly appreciated!

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    Joost, thanks for the effort, thast some good info there,

    Always shoot manual and dial in my own settings
    I was happy with the exposure of the shots
    It is this I am trying to minimise
    Flash Dancing Honeyeater - Haven't IDed him yet

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    1: What is a strobist anyway?

    2: Honeyeaters is one word, no capitals; ditto thornbills and scrubwrens; fairy-wren has a hyphen.

    3: Might be Lewin's Honeyeater, but hard to say. Can you blow him up for me?

    4: Sorry, what was the question?

    Errr ...... Let's try this post again .....

    I'm guessing that you are having trouble with the birds moving when you trigger the flash, Mark. This sort of thing:



    (1D III, 500/4 with 25mm close-up ring, ISO 500, f/6.3, 1/1000th, 580EX-II & Better Beamer.)

    If this is what you mean by "flash dancing" then the problem lies in the ETTL flash metering method: it sends out a small, very fast pre-flash pulse, measures how much light comes back into the lens, and then decides how much power to put into the main flash.

    Birds have incredably fast reflexes, as you can see. I don't know what the delay between the pre-flash and the main flash is, but it's certainly just some small fraction of a second, and that is more than enough for more nervous species (like the White-naped Honeyeater above) to react. Notice also the rapidity with which they move: that shot was taken at 1/1000th of a second and while it's obvious that the wings are a blur, there is also blur around the head, ruining this as a shot - the eye pretty much always needs to be sharp.

    What can you do to minimise this? I can think of several methods.

    1: Use manual flash. If there is no flash metering, then there is no pre-flash, and you only have to contend with a much smaller reaction time. That should work, but you are going to have to be an absolute flash guru to figure out how to manage calculating the correct exposure when you don't know (a) where the bird is going to be, (b) what colour the bird is going to be, and thus (c) how much flash you are going to need.

    2: Find a place where the birds are in sunlight!

    3: Use the fastest possible exposure time. This works better with some species than with others. You'd be fine with (for example) a duck, but small, active birds react very, very quickly. (As you have seen for yourself.)

    4: Repeat, repeat, repeat. Most species get used to the flash and start ignoring it after a while. Some pay little attention the first time (robins, New Holland Honeyeaters, Shining Bronze-cuckoo are examples), some soon learn to ignore it (Eastern Spinebill, Rufous Whistler), some start every time but rapidly settle again (Grey Fantails are a classic for this), some never seem to really adapt to it and fly off every time (White-naped Honeyeaters in particular).

    I'm not sure what your fastest possible shutter speed is at that distance and with your gear, but 1/250th isn't really enough for small birds. Do you have a Better Beamer? Will the 40D synch with a 580EX at, say, 1/1000th?
    Tony

    It's a poor sort of memory that only works backwards.

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    Tony,
    I promise to get the naming correct from now on.
    Definitely not a Lewin's, but you have IDed one of the others for me, The White-naped Honeyeater, have a few with just that pose

    Better Beamer - No, but it is on my list
    40D will high speed sync up 1/1000 but in the light I had there is no way I can shoot that fast. But will have to try that next time, bump the ISO to 1600 and go faster, good call. Not confident in 1600 ISO on the 40D but have to try

    Manual Flash would be an option, at least in this spot as I was just waiting for the birds to come into the same spot each time, pretty much.
    Tried shooting, multiple frames as quick as I could with out using continuous mode (flash doesn't cycle quick enough) and did get a few with more natural pose.

    Looks like it just a case of perseverance, I hope to make a few trips back to this spot in the near future .

    Thanks for your time

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    Wait, you mean the birds are startled by the flashlight and thus you get strange looking poses? That probably happens because of the preflash going off - if you don't want that, you'll need to switch to non-automatic flashmode. Not so difficult, but you'll need some calculations to perform, similar to what I did there.

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    Birds are not necessarily startled by just the preflash, but also High Speed Sync if you are using shutter speeds above X-sync

    Tony I think the problem with using 1/1000 as a shutter speed is that it also causes multiple flash pulses. I'm guessing you used High Speed Sync, which unfortunately also sends out multiple pulses to illuminate the frame evenly, so it has the same downside for skittish birds as does a preflash
    Last edited by smorter; 30-03-2009 at 11:20pm.

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    Quote Originally Posted by smorter View Post
    Birds are not necessarily startled by just the preflash, but also High Speed Sync if you are using shutter speeds above X-sync
    Very true. Not to mention you'll loose a lot of power when using HSS - with the settings described in the start posting you won't be able to correctly lit the scene anyway.

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    My thanks to Jev and Smorter for contributions so far, and to Mark for starting what is turning into a really useful thread.

    I can't see that reaction to high-speed flash thing, Smorter. OK, they are incredibly quick, but reacting to the flash pulses in less than 1/1000th of a second? Some birds react to the sound of the mirror flipping up (one of the things you do when shooting without flash is fire plenty of shots so that they get used to the shutter noise, most species (but not all) do that quite quickly) but that's in the order of 1/20th of a second when you are not using flash. There is a longer delay betwen shutter-press and shutter actuation using flash, presumably because of the time required for the pre-flash - at least there seems to be as the shutter doesn't go off as quickly as I expect when I'm using flash.

    Now, to doing it with manual flash settings. Here is a challenge! There is no way you could ever calculate the correct settings and make the adjustments in the very brief time you have (until the bird settles, we don't know how far away it's going to be, what the background is going to be, or what colour it is going to be - that White-naped Honeyeaer above, for example, needs around 2/3rds of a stop less flash than a more typical mid to dark toned bird, otherwise you blow the whites out). But I can come at the idea of calculating a "standard" setting in a given location under given lighting conditions, and then adjusting up and down from there on the fly by guess and by god. (After all, using ETTL we are already estimating the manual exposure settings for ambient light on the background and estimating the amount of flash exposure compensation.)

    That is going to be a major challenge just the same! You already have way too much to do in not enough time doing any sort of smal bird photography, it gets harder with TTL flash, harder again with manual flash. (I've actually been pondering doing that myself at Belinda's place where the drinkers come thick and fast in season, but I'll have to wait till the hot weather returns next year.)

    Last point: distance and power. The Better Beamer isn't terribly efficient; it's a fiddly damn thing to set up and you still spray a lot of light around where you don't need it, but is does make quite a difference to your reach. Wild guess: 3 x more reach? Something like that. But 20 metres is way too far - never mind whether the flash can do that distance, you want to be at less than 10 metres from a small bird prety much anytime you take a shot, and you don't start getting really good results until you get to around 5 metres. (As a rough rule of thumb, I reckon than once I have to use a close-up ring on my 500 - which has a minimum focus distance of 4.5 metres - I should be getting excellent results. Sometimes I put an extension tube on it when I'm just doing general walk-around birding - that means I can't take shots of anything that isn't pretty close, and though I obviously miss some shots, the ones I miss are mostly the ones I'd only be throwing away later anyway.)

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    Quote Originally Posted by Tannin View Post
    I can't see that reaction to high-speed flash thing, Smorter. OK, they are incredibly quick, but reacting to the flash pulses in less than 1/1000th of a second?
    Probably not, but HSS starts generating light before the shutter starts to move. Comparable to the preflash me thinks - enough time for the bird to react.

    Now, to doing it with manual flash settings. Here is a challenge! There is no way you could ever calculate the correct settings and make the adjustments in the very brief time you have
    So, you'ld have to be a bit lucky. I would suggest to take an educated guess on where the bird is most likely to be settling and set things up accordingly. Agreed, one would miss quite often but sometimes you'ld nail it. I really don't see an alternative if automatic preflash is not an option. Perhaps an old TTL flash might do a better job since it doesn't generate a preflash (but you'ld have to find a way to fool the flash sensor to sense how much light is generated). Hey - this is actually a good idea to dust of the old analog camera . Without kidding, perhaps an older automatic flash that runs in standalone mode is the solution? There are Metz flashguns out there that read the reflected light and cuts of the light when done without camera intervention... that might work.

    The Better Beamer isn't terribly efficient; it's a fiddly damn thing to set up and you still spray a lot of light around where you don't need it, but is does make quite a difference to your reach. Wild guess: 3 x more reach?
    If it allows 3 times the reach, that thing would be pretty efficient (3 x reach = 8 x the light!). I don't own a BB, but googling brings up values varying from 1 to 3 stops - and that is quite astonishing in my book.

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    Interesting stuff, Jev. I didn't know that HSS starts before the shutter opens. Next time I have the opportunity, I'll do some experimentation with manual HSS (no pre-flash) to see what sort of reaction time I get from the White-naped Honeyeaters. (These are a good test bird as they seldom fail to react to the flash, but (at Belinda's place) they are common and one calls in to drink every few minutes, so I can afford to spook them, confident that another one will turn up soon enough.)

    You have to be a bit lucky with bird photography all the time! Your method sounds like the way to go. In the sort of location where you are worlking with birds and flash - typically the atraction is food or (most often) water - there are usually only a half-dozen favoured perches, so it is perhaps feasable to set up on one and learn how much + or - to dial in for a couple of others. As it is (using ETTL) you are dialing in different flash and exposure settings for different species and different perches, and get to learn that (e.g.) the spot over on the left needs a wider aperture (weaker backlighting) and a bit more negative FEC (a little closer to the camera), so I guess that it's just one more complexity to get the mind around and the clumsy fingers to deal with.

    The 580EX II has an option to shoot using TTL rather than ETTL; I've never used it. Would that have the same effect as using an old flash?

    That 3 x number was just something I made up on the spot, but somewhere around a couple of stops ... that seems about right from my experience. You can certainly shoot from a good distance further away, and (using HSS) get up to insane shutter speeds if you are reasonably close - I'm not sure what the fastest I've used is, but up about 1/2000th or so works fine. And yep, you still get movement blur at that speed: to properly freeze a small bird in flight, I like to be at 1/3000th or better - which must be taking us well beyond poor light / flash territory!

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    Quote Originally Posted by jev View Post
    Very true. Not to mention you'll loose a lot of power when using HSS - with the settings described in the start posting you won't be able to correctly lit the scene anyway.
    The image I posted was taken with those settings Jev.

    I said/ guessed 20 mtrs, I certainly was not more than 20 mtrs probably closer, maybe even closer to 10 meters than 20.

    There is some really good info here, thanks to all that have offered advice.

    Manual flash in this situation would possibly work ok, set up waiting for the birds to land on that stick, dive into the water and then back to the stick.

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    Quote Originally Posted by Tannin View Post
    The 580EX II has an option to shoot using TTL rather than ETTL; I've never used it. Would that have the same effect as using an old flash?
    It probably won't work in combination with a digital. TTL works by measuring the light reflected from the film plain and cut off the flash when enough light has been detected. That works with film but unfortunately it doesn't work with digital sensors, probably due to the filters in front of the image sensor. That's why I mentioned the analog camera .

    There are other "automatic" flashguns out there that don't rely on TTL but have their own sensor. From the top of my head: I think Metz had a few, Braun, Vivtar and Sunpak probably made even more in this category. The vivitar 285 seems to be available quite well even today. However, if you're gonna' hunt for such a beast, make sure it has a trigger voltage not exceeding whatyour camera can handle or use a Wein Safe-Sync.

    from a good distance further away, and (using HSS) get up to insane shutter speeds if you are reasonably close - I'm not sure what the fastest I've used is, but up about 1/2000th or so works fine. And yep, you still get movement blur at that speed: to properly freeze a small bird in flight, I like to be at 1/3000th or better - which must be taking us well beyond poor light / flash territory!
    Why you would like to use HSS is beyond me, if you balance the flash such that it functions as a main light, movement of the bird is frozen by the flash and you wouldn't need those ridiculously fast speeds. Remember, shutter speeds faster than X-sync are made by creating a slit that move over your sensor - if the bird is actually fast enough chances are you will still see strange movement of the wings.

    Quote Originally Posted by MarkChap View Post
    I said/ guessed 20 mtrs, I certainly was not more than 20 mtrs probably closer, maybe even closer to 10 meters than 20.
    If it actually was 14 meters, you'ld win a full stop so that makes quite a difference . And ofcourse you mentioned -2/3 FEC. In addition, I am pretty sure the flash didn't work as main light, thus you'ld probably had some help from available light. Do you remember how much light actually was available at that spot?

    HSS works by pulsing the flash over the whole period your shutter is moving over the focal plain. If you maximize the flash in normal mode, it would generate a single burst of light, eating all available power in roughly a millisecond. When using HSS, the flash must be pulsed during the whole time the shutter travels over the film plain, equal to X-sync (4 or 5 milliseconds *). It can do that only if it doesn't consume all it's power in the first msec. That is the reason why it cannot generate as much light in HSS as in normal mode. Note that Canon for example specifies the guidenumber of the flash at 50mm to be 30 x 1.4, in HSS that number decreases to 15 x 1.4 meter (see "Major Specifications" on page 50 of the 580EX ownersmanual).

    *) In the owners-manual, Canon calculates with X-sync = 1/250", but be aware that this number is not valid for all camera's - if you've got one that has a slower X-sync the flash won't be able to generate that much light.
    Last edited by jev; 31-03-2009 at 6:19pm.

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    flash dance!

    hahahahaha!!!

    yeah just keep at em and they get bored of the flash or fly away. atleast thats what i do

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