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10-24-2010, 05:45 PM   #16
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QuoteOriginally posted by filorp Quote
yes i'v tried this.... the more i wrise the iso the more overexposure i get, iso 100 is ok, iso200 is just 2 times brighter iso 400 is 3times brigter and so on... everything in environment where you need 1/20s iso3200 f4 without the flash. The problem is that... my k20d works fine with the same settings and gear.....and with built flash everythins fine as well
I'm not sure what Metz flash you have but i have the 58AF-1. It will show TTL until connected with the camera in which it will show P-TTL. Does yours have the same display? Is it showing P-TTL? It sounds like the flash isn't communicating or is in Auto mode (which I'm sure you checked, just saying).

Sorry I can't help more. It is working for me at higher ISO. Here is one at 1600 but works well at 3200 too. But again, need a FEC of -1 to get it perfect.




10-24-2010, 05:56 PM   #17
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this is exactly what im talking about Cannikin, look haw badly k5 overexposes, tomorrow im calling service department....
jrforman i need -2 fec plus -1fec in the flashgun....
10-24-2010, 05:59 PM   #18
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Maybe it's just me, and I'm a beginner with lighting also, but 1/80, 200, f4, the Kx seems underexposed. The K5 seems more what I would expect at those settings. That's seems very open on the ap and short on the shutter for a flash. I could be wrong, though.
10-24-2010, 06:14 PM   #19
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QuoteOriginally posted by Rory Quote
Maybe it's just me, and I'm a beginner with lighting also, but 1/80, 200, f4, the Kx seems underexposed. The K5 seems more what I would expect at those settings. That's seems very open on the ap and short on the shutter for a flash. I could be wrong, though.
It was a very, very dark room; dark enough that I had trouble seeing through the viewfinder. I wanted it such that the only real source of light is the flash to eliminate any other variables. I just used these settings because it's what P mode on the K-5 gave me with the flash on.

But it shouldn't matter what the shutter/aperture are. Unless I'm mistaken, the whole point of P-TTL is such that it pre-flashes to examine how the light affects the scene and adjusts the flash power accordingly. The K-x gives me basically the exact same exposure every time, no matter what I set the settings to. Yeah, I've noticed that the K-x consistently looks rather dark with the flash, but it is very consistent in giving me that exact same exposure each time.

In my testing with the K-5, testing with various apertures and shutter speeds, it's pretty clear that the flash is firing at full power every single time. f/5.6 produces an image that is roughly one stop less overexposed, f/8 one stop less, and so on. It's obvious the flash is not adjusting its power at all.


Last edited by Cannikin; 10-24-2010 at 06:45 PM.
10-24-2010, 06:25 PM   #20
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iv notice something else strange,Cannikin can you try to use some long telephoto lens like 70mm or longer and see whats happening.... At 70mm (da17-70)my k5 start to work ok... at 135(da50-135) as well, isnt it strange?
10-24-2010, 07:20 PM   #21
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QuoteOriginally posted by Cannikin Quote
It was a very, very dark room; dark enough that I had trouble seeing through the viewfinder. I wanted it such that the only real source of light is the flash to eliminate any other variables. I just used these settings because it's what P mode on the K-5 gave me with the flash on.

But it shouldn't matter what the shutter/aperture are. Unless I'm mistaken, the whole point of P-TTL is such that it pre-flashes to examine how the light affects the scene and adjusts the flash power accordingly. The K-x gives me basically the exact same exposure every time, no matter what I set the settings to. Yeah, I've noticed that the K-x consistently looks rather dark with the flash, but it is very consistent in giving me that exact same exposure each time.

In my testing with the K-5, testing with various apertures and shutter speeds, it's pretty clear that the flash is firing at full power every single time. f/5.6 produces an image that is roughly one stop less overexposed, f/8 one stop less, and so on. It's obvious the flash is not adjusting its power at all.
I'm wondering whether your flash is communicating correctly with the camera.
I don't have the K-5 yet, but I had a similar initial issue with the K-7.

Does the LCD screen on the Flash say "P-TTL"
Has the Flash Icon in the viewfinder stopped blinking ? - it should show a steady flash icon once it recognises the P-TTL flash.
Without both these two showing proper flash-camera communication, the flash will fire at Full Power, regardless.

When you set ISO 3200, and direct flash, is the minimum/maximum indicator on the flash LCD screen blinking ? (indicating too close within minimum P-TTL flash range).

...Edit...I just checked the AF540 manual. At ISO3200, 50mm focal length, the minimum direct flash range at f/5.6 is about 18 feet. Anything closer will be overexposed. If you add ambient lighting in a reasonably lit room, the minimum will be greater.

Last edited by kittykat46; 10-24-2010 at 07:30 PM.
10-24-2010, 07:51 PM   #22
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Indeed, I am not getting consistent results, but evidence is pointing at a communication issue.

The camera and flash are definitely detecting each other (flash reads P-TTL, camera detects and adjusts settings for flash), but many of the settings seem to jump around or be slow to respond, like the flash zoom. It also seems very inconsistent in allowing me to switch flash modes: sometimes it allows me to select Auto, sometimes it doesn't. Sometimes the flash fires at full power, sometimes it doesn't (going by the charge sound).

I did a bit of experimenting with wireless flash. I have very little experience with wireless so it turned out crappy, but it definitely worked a lot better than attached to the camera.

Thus, I am tentatively concluding that one of the hardware contacts in the hotshoe is bad. It's just not consistently sending the correct signals to the flash. This may need to be sent in for repairs.

Last edited by Cannikin; 10-24-2010 at 08:04 PM.
10-24-2010, 07:58 PM   #23
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Hi Cannikin, I have a K10D and the 540 flash - I find that sometimes when the flash is mounted on the camera the flash does not auto zoom. Often I have to besure it is fully pushed into the hotshoe and tighten the lock to get the Auto zoom to work properly.
Maybe try rubbing the hot shoe contacts with a dry cloth - just to be sure it is clean and you are getting a good electrical contact
I assume you have the camera set to Av or Manual mode. Have you tried in P mode?
Have you tied with the flash off camera in wireless mode?
That is the extent of my ideas - hope you get it working

10-24-2010, 11:13 PM   #24
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QuoteOriginally posted by Bobe416 Quote
Hi Cannikin, I have a K10D and the 540 flash - I find that sometimes when the flash is mounted on the camera the flash does not auto zoom. Often I have to besure it is fully pushed into the hotshoe and tighten the lock to get the Auto zoom to work properly.
Maybe try rubbing the hot shoe contacts with a dry cloth - just to be sure it is clean and you are getting a good electrical contact
I assume you have the camera set to Av or Manual mode. Have you tried in P mode?
Have you tied with the flash off camera in wireless mode?
That is the extent of my ideas - hope you get it working
All the lock actually does is drop a pin into the hot shoe to keep the flash from sliding off. I do agree however that you want to make sure the flash is always pushed completely on the shoe. I've had similar experiences only to discover that the flash was not fully seated.

10-25-2010, 06:55 AM   #25
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the camera is metering the black and over exposing it seems. What metering are you using spot or center...did you try matrix.
10-25-2010, 06:58 AM   #26
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by raising the ISO you increase the flash's power by like 4 stops. That is why it is over exposing also. I use this out doors for high speed sync. shooting at 400-800 increases power output and faster recycle times as the camera is more light sensitive. You just have to learn your equipment. My d90 does the same but my d70 did not do this as their metering is different.
10-25-2010, 08:12 AM   #27
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haw do you explain fact that using flash gun at manual mode 1/64 or 1/128 power you'll getting good results and when you switch to pTTL the same condition the same exposure you get white picture with histogram veeeeeeeryyyyy good exposed to the right?
10-25-2010, 08:25 AM   #28
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Manual Flash mode dependent on minimal communication with the camera - just trigger "Fire" so it all depends on your manual settings on the flash.
Auto Mode also mostly based on the Flash's own logic.

P-TTL, on the other hand, is dependent on the camera and flash "talking" to each other on camera ISO setting, aperture, lens focal length for the flash zoom, the flash GN power.
If that handshake is not happening properly, the results are easily Worse than what you can achieve with Manual or Auto Flash.
10-25-2010, 09:30 AM   #29
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QuoteOriginally posted by kittykat46 Quote
If that handshake is not happening properly, the results are easily Worse than what you can achieve with Manual or Auto Flash.
is it something we uset to call pTTL?
10-25-2010, 09:52 AM   #30
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QuoteOriginally posted by tigerzen Quote
by raising the ISO you increase the flash's power by like 4 stops. That is why it is over exposing also. I use this out doors for high speed sync. shooting at 400-800 increases power output and faster recycle times as the camera is more light sensitive. You just have to learn your equipment. My d90 does the same but my d70 did not do this as their metering is different.
Yes, raising the ISO or any other exposure setting will affect the ambient lighting.

However, the whole point of P-TTL is to adjust the power of the flash, therefore when the flash is the primary source of lighting, the exposure should be the same no matter what you set the ISO to (as long as you don't go outside the limitations of the flash). I have verified this many times with my K-x: with the flash being the primary/only source of light, and the flash set to P-TTL, the exposure looks exactly the same at ISO 1600 and ISO 200, as it should.

Under the same conditions, my K-5 is not doing that. It is merely firing the flash at full power no matter what the settings are. It doesn't do that in Auto mode, it doesn't do that in wireless P-TTL, and it doesn't do that with the pop-up flash. This is quite obviously a hardware communication problem, possibly stemming from a bad contact somewhere in or around the hotshoe.

QuoteQuote:
the camera is metering the black and over exposing it seems. What metering are you using spot or center...did you try matrix.
Yes, I've thought of that and had tested matrix, center weighted and spot. Makes more or less no difference.
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