[taiweitai]

After i got used to the Metz 50 that i bought for a while, i just decided to take a step forward 2 months ago to buy a 540 FGZ to pair with the Metz and start taking some advantage of the wireless p-ttl feature. Well, It did not work as what i thought and i figure it must be me....

I failed to understand the concept of "Master" and "Control" mode

The concept i had is if you have two flashes, it will serve as two light sources which fire the same time...... I know i was wrong after a while...... Here is my setting - i have the 540fgz on the hot shoes and the Metz 50 at a remote location on wireless slave mode, both face the object directly straight and on the left. As i set my 540 FGZ on "Master" mode, the slave Metz 50 would fire first before the shutter and the 540 would light up when the shutter is open - which object takes the light mostly from the 540. It would do the opposite thing if i am on "control" mode. So now i try to bounce off a wall or an umbrella with the slave flash, delay the light off the"pre-flash" so the object catch the light off the slave.

I don't find a wall or have the leisure to bring an umbrella sometime to shoot picture at a very open area sometime, that's why i was expecting two flashes would have a balance distribution on something i am shooting. I read the manual but that does not help, Any two cents here?

[SOldBear]

I don't have a Metz 50 so I can't help you much when it comes to how to set it up. I do however have 2 copies of Pentax AF540FGZ and I have no problem setting them up in wireless mode, either with one attached to the camera and triggering the other one, or both of them triggered by the built-in flash.

From what I know, the only difference between "master" and "control" is that the "control" flash fires with reduced power. The idea is that the light from the "control" flash contributes insignificantly to the exposure (at least in theory). I think the "master" flash and the "slave" flash fire with the comparable power.

I have some questions. I'm not challenging you, just trying to understand your problem.

1. You wrote "As i set my 540 FGZ on "Master" mode, the slave Metz 50 would fire first before the shutter and the 540 would light up when the shutter is open." What triggers the Metz 50 so it fires first? How do you know that the Metz 50 fires before the shutter? If you don't know for sure, I suggest you to (1) take a photo in front of a mirror, with both flashes visible so you can tell which one fires during exposure, and (2) take a photo with the camera in 2 second delay mode. The preflash strobe will be separate by the main strobe by 2 seconds and you can tell which flash fires when.

2. You wrote "i try to bounce off a wall or an umbrella with the slave flash, delay the light off the"pre-flash" so the object catch the light off the slave." How long the delay do you expect? With light traveling at 300,000km/s, I imagine the delay is pretty short and I'm not sure if it makes any difference.

Edit to add: I have a feeling your Metz 50 is triggered by the preflash strobe from the 540. If you use the camera in 2 sec delay mode, you can definitely tell whether this is the case. It it is, the Metz 50 is set up incorrectly (as a "dumb" optical slave).

[taiweitai]

Thanks Soldbear for your detail explanation.

Now i really find out what the problem is , its the Metz 50 !! I took your suggestion to take a bunch of pictures in front of the mirror and try to nail down whats really happening during that split second. It works fine in the first few shots, two flashes fire up the same time under Master or control mode.......but not until a few shots after, the Metz 50 did not show itself on the picture. I did few more shots, making sure the Metz has the ready green light on before i fire and i look into the Metz unit with dead eye to make sure it really did fire when i press the button. Then i Took one more shot. The Metz really did fire " almost " the same time with the Pop up and the 540 but there is very tiny lag between them........so i did a bunch more test shots without changing anything. It appears the Metz is inconsistently "hit or miss" the time when the picture is taken. I did little bit more research by turning the 540 FGZ off, and the problem still exist ! (about 70% of the shots are ok) If i use the 540 itself, every shot appears to be ok.

I am not sure if that is the nature of Metz pairing with Pentax flash but i will give Metz a call to see if this is a defective unit.

Did you ever see this problem when you have your 540s working together?

I don't have a Metz 50 so I can't help you much when it comes to how to set it up. I do however have 2 copies of Pentax AF540FGZ and I have no problem setting them up in wireless mode, either with one attached to the camera and triggering the other one, or both of them triggered by the built-in flash.

From what I know, the only difference between "master" and "control" is that the "control" flash fires with reduced power. The idea is that the light from the "control" flash contributes insignificantly to the exposure (at least in theory). I think the "master" flash and the "slave" flash fire with the comparable power.

I have some questions. I'm not challenging you, just trying to understand your problem.

1. You wrote "As i set my 540 FGZ on "Master" mode, the slave Metz 50 would fire first before the shutter and the 540 would light up when the shutter is open." What triggers the Metz 50 so it fires first? How do you know that the Metz 50 fires before the shutter? If you don't know for sure, I suggest you to (1) take a photo in front of a mirror, with both flashes visible so you can tell which one fires during exposure, and (2) take a photo with the camera in 2 second delay mode. The preflash strobe will be separate by the main strobe by 2 seconds and you can tell which flash fires when.

2. You wrote "i try to bounce off a wall or an umbrella with the slave flash, delay the light off the"pre-flash" so the object catch the light off the slave." How long the delay do you expect? With light traveling at 300,000km/s, I imagine the delay is pretty short and I'm not sure if it makes any difference.

Edit to add: I have a feeling your Metz 50 is triggered by the preflash strobe from the 540. If you use the camera in 2 sec delay mode, you can definitely tell whether this is the case. It it is, the Metz 50 is set up incorrectly (as a "dumb" optical slave).

[SOldBear]

As stated, I don't have any problem with 2 Pentax 540 flashes.

But your test is still not complete. You need to run another test with:

- Camera in 2 second delay mode.
- Pentax 540 attached to the camera, in wireless mode (either control or master is OK).
- Metz 50 off camera, in slave mode.

The sequence is like this:

1. Hit the shutter button.
2. The Pentax 540 fires the preflash strobe. The Metz 50 should NOT fire.
3. The camera's mirror goes up.
4. 2 second delay.
5. The shutter opens. The Pentax 540 fires the main strobe. The Metz 50 should fire.
6. The shutter closes.

If the Metz 50 fires in step 2, the problem is that it is set up incorrectly.

Please run the test and report back.

[taiweitai]

Tell me what does this sound to you:

1. Hit the shutter button. PRESSED
2. The Pentax 540 fires the preflash strobe. The Metz 50 should NOT fire. BOTH FIRED, not sure how this happened but the Metz is in Slave mode not Servo Manual ( aka dump slave)
3. The camera's mirror goes up. YES
4. 2 second delay. YES
5. The shutter opens. The Pentax 540 fires the main strobe. The Metz 50 should fire. ONLY 50% of the time METZ fired
6. The shutter closes. HAPPENED

[taiweitai]

Like you said, the setup is incorrect but what should the settting be ?

I still do not see why the Metz is only half working on Step 5.

[taiweitai]

Ok, just run another test to fireproof this series of experiments

I ran the same test, instead i used the Pop up to control either the Metz or Pentax in slave mode- only one of them each time.

Pentax and Metz fired at pre-flash with the pop up, but Metz still failed to fire the second flash most of the time .....

[SOldBear]

As stated, I don't have the Metz 50 flash.

I have a feeling the Metz is in the "dumb" slave mode. But I don't know how to get it out of that mode yet.

Let me read the manual and post back.

I forgot another test:

- In front of a mirror.
- Pentax 540 in Manual mode, attached to the camera.
- Metz 50 in slave mode, off camera.
- Take a photo.

Does the Metz 50 also fire with the Pentax 540?

[taiweitai]

Just make sure we are on the same page: The 540 is not possible to have M mode on wireless setting (one click right from off), i set M mode on "On" mode (two click right from off)

Anyway, on M mode the Metz does not fire at all since the 540 is not on Wireless mode.

An Interesting finding: When 540 is on Master Mode , the Metz only works part time; on Control Mode, the Metz works fine. That lead me to the misconception at the very begining

[taiweitai]

Metz has two mode for wireless:
SL on display: P-ttl Slave mode, power goes automatically with P-ttl setting
SERVO on dsplay: Dumb wireless slave with manual power setting

As stated, I don't have the Metz 50 flash.

I have a feeling the Metz is in the "dumb" slave mode. But I don't know how to get it out of that mode yet.

Let me read the manual and post back.

I forgot another test:

- In front of a mirror.
- Pentax 540 in Manual mode, attached to the camera.
- Metz 50 in slave mode, off camera.
- Take a photo.

Does the Metz 50 also fire with the Pentax 540?

[SOldBear]

The test with the Pentax 540 in manual mode was to make sure the Metz 50 was not in dumb slave mode. You verified that the Metz 50 was in p-TTL wireless mode.

I still can't explain why "When 540 is on Master Mode , the Metz only works part time; on Control Mode, the Metz works fine."

When you ran the first test (wireless p-TTL mode in front of a mirror), what were the ISO setting and the aperture setting?

If the ISO setting was high (400 and above), and the aperture was large (f/5.6 or larger), can you re-run that test with the lowest ISO setting and small aperture (f/16 or f/11). Frankly, I don't really know what the test will tell, but I'd like to find out.

And also run another test with the built-in flash as the controller/master and the Metz 50 as the slave (no Pentax 540).

Other than that, I tend to agree with you that the Metz is defective.

2. The Pentax 540 fires the preflash strobe. The Metz 50 should NOT fire. BOTH FIRED, not sure how this happened but the Metz is in Slave mode not Servo Manual ( aka dump slave)

I was wrong. The Metz 50 should fire (which you did verify). That is to send an acknowledgement to the control/master flash and also for metering.

[taiweitai]

When you ran the first test (wireless p-TTL mode in front of a mirror), what were the ISO setting and the aperture setting?

If the ISO setting was high (400 and above), and the aperture was large (f/5.6 or larger), can you re-run that test with the lowest ISO setting and small aperture (f/16 or f/11). Frankly, I don't really know what the test will tell, but I'd like to find out.

The first test i ran includes these settings .......no particular finding but if the shutter speed is longer than 0.5s, the metz tends to have no problem at any condition at all .........

This is out of topic but found out the wireless sensor of Metz is off the side not like the 540 at the main window. So now i have to ensure the flash body is facing sideway when i run it on wireless.

Yup...... i guess i d better call a Metz rep to figure this out.........