High Speed Sync Flash at Bosque

[Jon Sostarich]

I am at Bosque Del Apache and I am taking photo’s of Sandhill Cranes as they fly over me at the Crane pools (technique described in Arthur Morris Bosque site guide). I am trying to use High speed sync flash to fill the underside of the Cranes body as they fly over. I am using the following equipment:

Canon 1Ds Mark II camera
Canon 400mm 4.5 lens
Canon 580 EX flash with Better Beamer
Quantum Turbo SC battery for flash.

I had problems with getting Av and Tv modes to work correctly so I switched to Manual mode.
In Manual mode I set my shutter speed to 1250sec, Aperture to F5.6 and changed my iso setting until the camera’s meter reading was set to 0 exposure compensation.


I need to be able to control the flash output(decrease the intensity).

When I am using the camera in manual mode do I need to run the flash in manual mode or can I use ETTL II (with a negative flash compensation)?

I have read this thread
http://birdphotographers.net/forums/...ad.php?t=14466

and I also read the Flash section in “The Art of Bird Photgraphy II”.

[Jon Sostarich]

Two pictures I have taken. The left side is without flash and right side is with flash(too strong of fill).

[John Chardine]

If you are using Manual flash you simply need to adjust your flash output until you get the desired result. You can set the flash output in Manual mode in 1/3 stop increments down to 1/128 of full output. Simply press the Set button and spin the wheel. The amount you compensate will depend on the distance to subject and your shutter speed. With H-synch, the faster your shutter speed the lower the flash output, and of course the farther your subject is away from you the weaker your flash will be on the subject. Looking at your "over-flashed" wing, to me it looks pretty good, but if you think there is too much fill here then cut the light my 1/2 (1 stop) and see what that does. Fine tune as necessary.

[Alfred Forns]

Hi Jon I'm amazed getting that much light on the bird at 1/1250 Fully agree with John, lots of good info.
Might suggest going to ETTL and just dial down the flash as needed. We normally go to manual when we need full output.

One thing you can do to bracket the flash output by doing three images in rapid succession. The first will be at full flash power, the second somewhat less since the capacitor has not charged and the third probably very little of no flash at all. With your battery you might get something out of the third !!! Good luck !!

[Robert Amoruso]

Jon,

Remember that you cannot use the flash in Manual and the camera in automatic. The Mark II cameras will flash 1/8000 shutter speed when you try this (Mark III cameras don't do this).

ETTL mode and using the exposure compensation dial (press button in first), go plus to increase output and minus to decrease output. Also know that as the speed gets higher, the flash output is less in High Speed Sync.

[Jon Sostarich]

Thanks Robert, I was trying to use the flash in manual mode while using Tv exposure mode(It doesn’t work that way as you pointed out). Today I used the flash in ETTL II mode with Tv camera exposure and things worked much better. The only thing I need to learn now is how much to dial the flash back. The second picture I posted with flash used was not a cropped picture. Using a 400mm lens I could only get the left wing of the bird in the picture. The thing that makes it difficult is that all the Cranes are not flying at the same height. What do you look for in the LCD display of the camera to determine how much flash to use(make in field adjustments)?

[Arthur Morris]

Hi Jon, There are mny complex issues here. Many. In your "too much flash" image the image looks as if it were made in very low light. While the image without flash looks as if it were made in fairly or even very bright sun....

#1: why do you say that the flashed image it is "too much flash"?
#2: if you are using flash in very low light such as right at or just after sunset (or before sunrise) the flash will have a far greater effect on the image than in other conditions. When shooting flash flight or flash blurs as it gets darker and darker you will find that you need to dial back the flash as the light levels get lower....

Once I hear back from you we can proceed.