K10D graduated exposure across frame
Posted 21/03/2010 - 22:47
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Contact Pentax and send them your photos and see what they say.
Stefan
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Posted 29/03/2010 - 18:13
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UPDATE:
Finally managed to have a play around under similar conditions and found that using the camera on manual with a shutter speed of 1/125 solved the problem - no grey band visible - so I can only assume it is some sort of flash sync effect.
Cheers for everyones earlier input by the way.
H
Finally managed to have a play around under similar conditions and found that using the camera on manual with a shutter speed of 1/125 solved the problem - no grey band visible - so I can only assume it is some sort of flash sync effect.
Cheers for everyones earlier input by the way.
H
Posted 29/03/2010 - 18:15
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Glad you solved it but still very strange though ^^
Stefan
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Posted 29/03/2010 - 18:21
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Anvh wrote:
Glad you solved it but still very strange though ^^
You're not kidding about strange - the longer shutter speed resulted in a more exposed picture aswell - just like when using availble light. I cant see how that is possible when using flash!Glad you solved it but still very strange though ^^
H
Posted 30/03/2010 - 10:35
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Haworth wrote:
You're not kidding about strange - the longer shutter speed resulted in a more exposed picture as well - just like when using available light. I can't see how that is possible when using flash!
H
Is it because it depends on how much ambient light there is? If I understand Matt's book properly, you use aperture to control the contribution of the flash and shutter speed to control the contribution of the ambient light. Looking at those shots I am teaching Grandma to suck eggs here...
You're not kidding about strange - the longer shutter speed resulted in a more exposed picture as well - just like when using available light. I can't see how that is possible when using flash!
H
Kris Lockyear
It is an illusion that photos are made with the camera… they are made with the eye, heart and head. Henri Cartier-Bresson
Lots of film bodies, a couple of digital ones, too many lenses (mainly older glass) and a Horseman LE 5x4.
It is an illusion that photos are made with the camera… they are made with the eye, heart and head. Henri Cartier-Bresson
Lots of film bodies, a couple of digital ones, too many lenses (mainly older glass) and a Horseman LE 5x4.
Posted 30/03/2010 - 11:30
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Hi Kris,
I had thought that might be the case, but tried a shot with the flashes turned off to see the effect of the ambient light in the room. The frame was totally black save for a few red pixels (what would be the extreme highlight in the shot with the flash), so ambient light wasn't a factor here (the room was quite dark).
I'm really scratching my head with this - at least I've found a way round it but I would like to get to the bottom of it just for peace of mind's sake!
Cheers
H
I had thought that might be the case, but tried a shot with the flashes turned off to see the effect of the ambient light in the room. The frame was totally black save for a few red pixels (what would be the extreme highlight in the shot with the flash), so ambient light wasn't a factor here (the room was quite dark).
I'm really scratching my head with this - at least I've found a way round it but I would like to get to the bottom of it just for peace of mind's sake!
Cheers
H
Posted 30/03/2010 - 12:26
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You're using multiple flash with wireless triggers if so could it be that one flash is out of sync.
So one flash flashes to early capturing the shutter and with the second flash that does work al right making the shutter grey instead of black.
So one flash flashes to early capturing the shutter and with the second flash that does work al right making the shutter grey instead of black.
Stefan
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Posted 30/03/2010 - 14:34
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Anvh wrote:
You're using multiple flash with wireless triggers if so could it be that one flash is out of sync.
So one flash flashes to early capturing the shutter and with the second flash that does work al right making the shutter grey instead of black.
With the speed of light being what it is, there is no way that any one flash could fire early. They flash simultaneously when the shutter is open. If the synch was wrong it would be the camera that simply closed the circuit at the wrong time and that would affect all flash units.
You're using multiple flash with wireless triggers if so could it be that one flash is out of sync.
So one flash flashes to early capturing the shutter and with the second flash that does work al right making the shutter grey instead of black.
Best regards, John
Posted 30/03/2010 - 14:47
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Sorry John but I'm having problems with my flash as well the AF540FGZ, and I know some others that have sync problems with certain flashguns and don't have a problem at all with others so there is more going on.
If one flash doesn't make the 1/180 or 1/125 mark but flashes later (sorry had that one wrong with my previous comment) at 1/100 mark it will catch the trailing shutter curtain in the frame when shooting at 1/180 or 1/125.
If one flash doesn't make the 1/180 or 1/125 mark but flashes later (sorry had that one wrong with my previous comment) at 1/100 mark it will catch the trailing shutter curtain in the frame when shooting at 1/180 or 1/125.
Stefan
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
Posted 30/03/2010 - 15:01
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It would have to flash after the shutter was partly closed, but the exposure difference would be a sharp edge.
Shutters can of course "taper" - slowing down as they reach the end of their travel. They can also bounce back slightly instead of closing properly, but this can easily be tested by using just one flash, or even the built in flash, to establish that the shutter gives an even exposure.
Shutters can of course "taper" - slowing down as they reach the end of their travel. They can also bounce back slightly instead of closing properly, but this can easily be tested by using just one flash, or even the built in flash, to establish that the shutter gives an even exposure.
Best regards, John
Posted 30/03/2010 - 15:12
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Yes that's true John didn't thought about that in such a way... *sighs* this is quite a mystery.
Stefan
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
K10D, K5
DA* 16-50, DA* 50-135, D-FA 100 Macro, DA 40 Ltd, DA 18-55
AF-540FGZ
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