Dual Speedlites - DPChallenge Forums

Sigma 35mm f/1.4 DG HSM for Canon

11/30/2006 11:02:00 AM · #1

Well, I just received my 580EX (I already had a 430EX). I could use a whole learning thread on using these in tandem (any takers?), but I will post the following questions and hope that some one can lend a hand (or two).

1. The 580 Manual discusses wireless master/slave configurations. It never shows the on-shoe 580 as being fired though. They show the on-shoe 580 simply controlling slaves. I know that both can be used (I have already tested that) but my question is on controlling the ratios. It seems to me that the 580 will let my specify flash ratios between various slave groups, but not between the master and the slave. The 580 will show RATIO A:B or RATIO A:B:Câ�¦ but not RATIO: MASTER:A. I have the 430EX set as slave â�� so it is channel 1 A slave. I have the 580 set as master and it shows channel 1 (no A or B designation).

2. Just did a really quick set of tests last night. I have both flashes firing together. I had the 430EX sitting about a foot away from and pointing at the subject (a computer mouse) and had the 580 on the camera bouncing from the ceiling. I was standing about 3 feet from the subject. I had the camera mode set to manual. I was using my Tamron 28-75 2.8. I dialed in a pretty wide aperture. I was expecting to use a pretty quick shutter speed as well â�� but to get proper exposure I had to use a shutter speed of more than a second. I donâ��t understand why that would be the case. I had the 580 ratios set â�� I tried pretty radical ratios in both directionsâ�¦ but I was still needing slow shutter speeds.

3. When I put my Tamron 28-75 and the 430EX on my camera, the flash recognizes and adjusts the focal length of the lens. When I put the 580EX on, it does NOT recognize and adjust the lensâ�� focal length. And I donâ��t see any way to tell the flash to automatically detect the lens focal length. It seems to me that it either works and the flash uses automatic focal length detection unless you override it with the zoom buttonâ�¦ or else you simply have to manually do it yourself. Will I continually need to set the zoom on my 580EX? That canâ��t be rightâ�¦

By the wayâ�¦ I have read just about everything in the forums that seemed relevant. I am trying to compile a little help-file for myself (using that information).

Ubersteiny

Canon EOS-5D Mark II

11/30/2006 11:20:54 AM · #2

when in manual are you shooting on the 580 in ETTL? becaue that can be your problem as ttl doesnt read on manual so you need to set your own output on both flashes, try setting it on Program using ETTL and see how that works.

and the head should zoom automatically, is it set to auto?

dwterry

Canon EOS-1D Mark III

Canon EF 24-70mm f/2.8L USM

11/30/2006 11:25:40 AM · #3

The master (if it is set to fire during the exposure) is always in the A group. You can set your slaves to a different group if you want to do ratios. So if the slave is in the B group, then you have a Master to Slave ratio. If you put a slave into the C group, then no ratio adjustment is performed.

Your 580 should be detecting focal length. If it's not, then something is amiss. You may need to exchange it if it's brand new or send it in for service. I would first check the contacts and make sure everything is clean.

11/30/2006 11:38:01 AM · #4

Noisemaker: The 580 is on ETTL. There doesn't seem to be a way to TELL the flash to use AUTO zoom. You can change the zoom and that is all.

Nikon AF-S Nikkor 70-200mm f/2.8G ED VR II

11/30/2006 11:40:44 AM · #5

David

Aha! That makes sense. I will set the 430EX to group B and then do ratios.

Also.. Is it possible that the lens rather than the flash has a problem which could keep the 580 from reading it?

MattO

Nikon D4

11/30/2006 11:42:21 AM · #6

I use the 580 and a 420 together and have no problems. I use ETTL and everything auto. Turn on the master switch on the 580 on the hotshoe. Position the 420 and turn it to slave and channel A and then go. Works flawlessly. And so simple even a big dummy like me can do it.

MattO

11/30/2006 11:44:37 AM · #7

Originally posted by santaspores:

Noisemaker: The 580 is on ETTL. There doesn't seem to be a way to TELL the flash to use AUTO zoom. You can change the zoom and that is all.

The 580EX autozoom only works when the flash is pointed straigh ahead. If it is aimed up or slightly down (for close-ups) the auto zoom won't work. It is easy to accidently aim the flash slightly down (there would be a flashing icon on the flash).

Canon EF 24-70mm f/2.8L USM

11/30/2006 11:51:21 AM · #8

p3wiz

Another Aha! I love you people. I am sure that that is why the autozoom wasn't working then.

That begs a question though... do I really need to worry about autozoom? Can I just ignore that - or do I need to dial in my zoom lengths when pointing the head up?

dwterry

Canon EOS-1D Mark III

11/30/2006 11:55:32 AM · #9

Originally posted by p3wiz:

Ah yes, been there done that!

11/30/2006 12:04:08 PM · #10

As I understand the Autozoom it is used to either focus the flash to only the area that the lens is covering (i.e. get longer range) and the other reason is to reduce the amount of wasted light if it is not needed.

When bouncing the flash you are looking for wide and soft light so the zoom function would not be helpfull.

btw do you have an Omni bounce yet? or something similar?

11/30/2006 12:06:58 PM · #11

p3wiz

I have a clear lightsphere II for the 580 and an omnibounce diffuser for the 430.

11/30/2006 02:02:22 PM · #12

I have my own question about speedlites. Is it possible to get the flash off the camera hotshoe? I have seen the 2' cord (about $90 cdn) that is intended for a flash bracket, but I don't think 2' will make a difference. I have seen the Cannon wireless transmitter for $300 cdn which is way too much. Anybody have any other ideas?

Sigma 35mm f/1.4 DG HSM for Canon

11/30/2006 02:32:21 PM · #13

p3wiz: Check this.

But you can get the Canon st-e2 for about $200.

Ubersteiny

Canon EOS-5D Mark II

11/30/2006 02:43:39 PM · #14

i hate how the 430 doesnt have a freakin pcsync jack!

11/30/2006 03:23:25 PM · #15

Originally posted by santaspores:

p3wiz: Check this.

But you can get the Canon st-e2 for about $200.

I took a look but I'm not sure what it is trying to tell me. How would that work with my 350D and 580EX? Would the E-TTL still work?

12/01/2006 08:34:45 AM · #16

p3wiz,
This method will allow you to remotely trigger your flash. However, I have never used this method. Perhaps someone who has used a pc cord connection between the 350D and the 580EX could help. I would imagine that it is a very common setup. The instructions on strobist are really just showing you how to increase the length of the pc cord. I bet you could also increase the length of the canon off camera shoe cord in a similar manor, but again, I have never done so.

cheekymunky