topic Re: What are the flash durations at the various power levels for the 600EX-RT? in Speedlite Flashes

What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Tue, 07 Jun 2016 04:06:29 GMT

Most flash makers publish the flash durations for the various power levels in the manual, but Canon does not. When photographing very high speed action, such as hummingbird wings, it is important to have the flash durations quite close to avoid ghosting. It would be nice to be able to mix various flashes, so it would be helpful to know the flash durations. Anyone know where this info is published? I am curious to know if the flash durations for the 430, 600, and perhaps even the 580 II are close enough. I could try it, but sometimes I must mix Canon speedlites with other flash brands. Here is a male rufous hummingbird using 1/32nd power on manual. Five 600's were used.

Re: What are the flash durations at the various power levels for the 600EX-RT?

Peter — Tue, 07 Jun 2016 15:31:04 GMT

Output level	Manufacturer spec	t0.1 metering
1/1	1/833	1/285
1/2	na	1/1400
1/4	na	1/2800
1/8	na	1/4600
1/16	na	1/6500
1/32	na	1/7500
1/64	na	<1/8000
1/128	na	<1/8000

Is that what you mean? 580II EX.

This numbers below are measured from a photodiod. 580 EX.

1/1 power = 1/1000 second
1/2 power = 1/2000
1/4 power = 1/4000
1/8 power = 1/9000
1/16 power = 1/15000
1/32 power = 1/21000
1/64 power = 1/30000
1/128 power = 1/35000

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Thu, 09 Jun 2016 16:47:53 GMT

Thanks so much! This will give me some help in pairing up different speedlites.

Re: What are the flash durations at the various power levels for the 600EX-RT?

Peter — Fri, 10 Jun 2016 08:06:28 GMT

The two speedlites have been different measured. The first one with t0,1.

t0.1 duration i.e. the time between 10% of the maximum intensity is reached and back down to 10% towards the end of the flash discharge,

The 580EX has been measured just by a photocell.

Re: What are the flash durations at the various power levels for the 600EX-RT?

Peter — Fri, 10 Jun 2016 08:09:31 GMT

430exII

Output level	Manufacturer spec	t0.1 metering
1/1	na	1/350
1/2	na	1/1630
1/4	na	1/3000
1/8	na	1/4300
1/16	na	1/5250
1/32	na	1/5600
1/64	na	1/6500

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Fri, 10 Jun 2016 09:30:30 GMT

I don't think I can trust this data. I know when I see the flash durations posted by Nikon and Sunpak in their flash manuals, the durations are much shorter in the 1/16 to 1/64 power range. Something isn't right. I was hoping someone has seen where Canon has posted this info somewhere. I have asked Canon to put this info in their manuals, but they don't get the need for it and so far my requests have done no good. Thanks for trying!

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Fri, 10 Jun 2016 09:33:34 GMT

For example, here are the flash durations for the Nikon SB-910. Notice how short the duration is at 1/16 and 1/32 power.

Flash duration

1/880 sec. at full output.

1/1,100 sec. at M 1/2 output.

1/2,550 sec. at M 1/4 output.

1/5,000 sec. at M 1/8 output.

1/10,000 sec. at M 1/16 output.

1/20,000 sec. at M 1/32 output.

1/35,700 sec. at M 1/64 output.

1/38,500 sec. at M 1/128 output.

Re: What are the flash durations at the various power levels for the 600EX-RT?

Peter — Fri, 10 Jun 2016 10:21:28 GMT

SB-700 Flash Duration Times

The next table shows specs versus test result for all full stops down to 1/128, as far as the measurement device could capture the durations (the metering range ends at 1/8000 seconds).

Output level	Manufacturer spec	t0.1 metering
1/1	1/1042	1/305
1/2	1/1136	1/1000
1/4	1/2857	1/2300
1/8	1/5714	1/4000
1/16	1/10000	1/5250
1/32	1/18182	1/8000
1/64	1/25000	<1/8000
1/128	1/40000	<1/8000

While the results are similar to the SB-600, they differ a lot from the data in the official Nikon table in section H-17 of the instruction manual. Overall, what’s probably most relevant to note here is that the speedlight’s 1/1 flash duration is in line with other model of accessory flash.

...

t0.5 is the time between the moment where the flash intensity curve starts to exceed 50% of the maximum intensity point and the moment where the falling intensity curve goes underneath the 50% maximum level again. The t0.5 time is shorter by definition and therefore used by most manufacturers, e.g. Nikon.

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Fri, 10 Jun 2016 11:39:44 GMT

I guess I will just do what I always do and use the same flash units when doing high speed action photography. I know if I set 1/16, and now use primarily 1/32 power levels, the short duration freezes hummer wings quite nicely. I learned about the problem of mixing flash durations several years ago when I used 1/16 power on the hovering hummers while I set the flash lighting the background to 1/4 power to light a larger area evenly. I got a dark edge along the wings and wondered what was causing it for a few days. Eventually, I realized the 1/16 power flashes on the hummer freeze the wings, but the longer flash duration used by the background flash was still lighting the background once the lights on the bird had done its job.

In the first image the female black-chin is lit primarily with ambient, but some fill flash is used. The male calliope wings are allowed to blur with all flash by using 1/2 or 1/4 power levels. The third image is all flash at 1/32 power to freeze motion, and finally is the setup from last year. I made major improvements this year to the setup so it works a lot better to produce better poses and colors in the gorget.

. The wings moved a little preventing some of the background from being properly exposed because the wings were blocking a sliver of the background that was still being lit.

Freezing the wings is only one way to photograph hummers. I do use all ambient light a lot, sometimes mix ambient and flash, and even blur the wings with all flash by using 1/2 or 1/4 power as the longer flash durations at these power levels don't freeze the wings producing a more natural looking hummer. You can tell I spend way too much time with hummingbirds!

Re: What are the flash durations at the various power levels for the 600EX-RT?

diverhank — Sat, 11 Jun 2016 04:27:37 GMT

@JohnGerlach wrote:
Freezing the wings is only one way to photograph hummers. I do use all ambient light a lot, sometimes mix ambient and flash, and even blur the wings with all flash by using 1/2 or 1/4 power as the longer flash durations at these power levels don't freeze the wings producing a more natural looking hummer. You can tell I spend way too much time with hummingbirds!

I respect what you're doing but I don't like to see frozen wings on hummingbirds...they look like taxidermy specimens being hung up. I also dislike the look of flash on birds in general and especially hummingbirds.

I never use flash on hummingbirds and many have bought my pictures so freezing the wings... it's not the only way to go :). Edit: sorry I misread your post, I thought you said freezing the wings is the only way...you actually said only one way...

================================================
Visit my photos on Flickr
www.flickr.com/photos/tongho58

Hummingbirds:

https://www.flickr.com/photos/tongho58/albums/72157629307055479

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Sat, 11 Jun 2016 05:16:35 GMT

There are many ways to photograph hummers. I like all of the ways. Allowing the wings to blur does look more natural, but I find freezing the wings produces interesting shapes with the various places the wings show up in the image.

Re: What are the flash durations at the various power levels for the 600EX-RT?

RobertTheFat — Sat, 11 Jun 2016 13:31:01 GMT

@JohnGerlach wrote:

You must have spent a lot of time befriending your subjects, or I'd expect them to be terrified of that rig, with all its flashes and tripods. How did they react when they first saw it?

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Sat, 11 Jun 2016 14:19:00 GMT

Most hummingbirds are quite tolerant of humans and our stuff. They reacted by perching on the Speedlites and taking a dump. When I used wires to link the flashes, they always perched on the wires for their small feet handle the wire better. If you hold still, these hummers will perch on you finger if you hold it in front of the feeding tube, and I have had them perch on my shoulder. Most hummingbirds I have worked with in the US and Ecuador are quite tolerant of people, but they don't like quick movements!

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Sat, 11 Jun 2016 14:23:32 GMT

You do notice the Male Rufous Hummingbird at the end of the feeding tube. We now prefer using Hum-buttons as the sugar water container because it is easier to hide and you get better gorget colors and better poses. I made a Flickr page for my hummer workshop clients that shows many more images and offers some flash advice in the discussion section. Just look for Bull River Hummingbird Photo Workshops. It is private for posting to clients only, but anyone can view it.

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Sat, 11 Jun 2016 14:28:41 GMT

I do have a quite detailed article on using Canon Speedlites to photograph hummers, but I don't know where would be the best place to post it so folks can find it. Any advice? Although I have earned an excellent living at outdoor photography for forty years, I am compute challenged. I just learned how to post an image on the Internet a month ago, so a lot to learn about the web. At least cameras and their accessories are super easy for me.

Re: What are the flash durations at the various power levels for the 600EX-RT?

Waddizzle — Sat, 11 Jun 2016 19:56:23 GMT

@JohnGerlach wrote:
Most hummingbirds are quite tolerant of humans and our stuff. They reacted by perching on the Speedlites and taking a dump. When I used wires to link the flashes, they always perched on the wires for their small feet handle the wire better. If you hold still, these hummers will perch on you finger if you hold it in front of the feeding tube, and I have had them perch on my shoulder. Most hummingbirds I have worked with in the US and Ecuador are quite tolerant of people, but they don't like quick movements!

They're that tolerant? That's amazing. But, if they don't like quick movements, what happens when the flashes fire? ZOOM?

Re: What are the flash durations at the various power levels for the 600EX-RT?

JohnGerlach — Sat, 11 Jun 2016 20:07:44 GMT

Hummers new to the setup may back up when the flashes fire, and then return, but not sure if it is the flash or the shutter noise. After a visit or two, they ignore everything. Slow zooming isn't a problem, normally I zoom by simply switching the 1.4x converter on my Canon 200-400 which is built-in. After awhile, you could have the University of Michigan marching band stampeding through the set and they would not care.