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02-17-2014, 08:23 PM   #121
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QuoteOriginally posted by sinus007 Quote
Hi,
I have to add my voice to this thread. I notices a very long, about 1 sec, delay when shooting in PTTL mode. When I push the shutter button the pre-flash fires right away and then the main flash goes off along with the shutter. I have AF540 and the f/w is 1.02.
When I use the onboard flash the delay is much shorter but still visible.
I wonder if anyone got a word from Ricoh about it and/or if they're going to fix it.
1 sec seems too long for what we are experiencing here. Are you sure you don't have the flash mode changed to something like red eye reduction?

02-17-2014, 10:39 PM   #122
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QuoteOriginally posted by Lage Quote
Has anyone been in touch with Pentax/Ricoh about this? If so, any feedback?

Regards,
Lage
I did contact Pentax USA. But wasn't very successful in persuading them there is any problem. I think the more people complain, the better chance that they will take notice. Right now, I am not sure they are even aware there's any problem.
02-18-2014, 12:11 PM - 1 Like   #123
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QuoteOriginally posted by gosman Quote
PTTL is exactly as you explained Sinus. Pre-flash and then the big flash. That is what PTTL is!
Except that the interval between the preflash and main flash is very short and just barely discernible with the unaided eye. What Sinus is seeing is probably the red-eye reduction flash.

I had done some reverse engineering on the P-TTL flash system a recall that the interval between the pre-flash and main flash was of the order of a few tens of millisecond or less and is just barely discernible as being two flashes. Normally the interval exists mainly because of the time it takes to lift the mirror and actuate the iris and for the shutters first curtain to open fully - the mirror needs to be down and the aperture blades fully open for the exposure meter to measure the pre flash but then the mirror needs to get out of the way and the aperture blades closed to the chosen aperture before the shutter is released. Then once the first curtain is fully open the main flash burst will be fired,

The camera will of course need to do some calculations based on the light measured from the preflash burst and then instruct the flash at what intensity to fire the main burst. That however should take far less time than the mechanical activity that has to take place between the preflash and main flash so it does not really add any further delay to what already exists when not using the flash.

The odd thing with the K-3 is that having the flash switched on introduces a delay between pressing the shutter the mirror lifting. That is an interval during which there is absolutely nothing that needs to be done except ordering the pre-flash to go off. So the camera is just sitting doing nothing for several tenths of a second or else making itself busy doing something useless.

It is worth noting that on two other cameras I own, the K-r and K-30, there is no noticeable delay introduced by the flash. Some have mentioned that perhaps the K-3's delay is because it does more complex calculations and gets the exposure right rather than hurrying and getting it wrong. That the K-3 gets it right far more often than previous Pentax DSLRs is true but the flaw in this argument lies in the fact that any complex calculations needed would be done in the interval between the preflash and the main flash burst, which is determined solely by the time needed to physically move the mirror, aperture blades and shutter and not between pressing the trigger and issuing the preflash so it cannot possibly explain the delay we are experiencing.
02-18-2014, 11:05 PM   #124
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QuoteOriginally posted by lister6520 Quote
Some have mentioned that perhaps the K-3's delay is because it does more complex calculations and gets the exposure right rather than hurrying and getting it wrong. That the K-3 gets it right far more often than previous Pentax DSLRs is true but the flaw in this argument lies in the fact that any complex calculations needed would be done in the interval between the preflash and the main flash burst, which is determined solely by the time needed to physically move the mirror, aperture blades and shutter and not between pressing the trigger and issuing the preflash so it cannot possibly explain the delay we are experiencing.
I agree completely.

I think Pentax finally got the whole P-TTL thing right. Then they told management and this is what transpired:

"Wait? It works? "
"Yes"
"You mean our P-TTL actually works flawlessly?"
"Erm, yes!"
"This is unacceptable, we have to do something to screw it!"
"But it's too late, we're releasing next week."
"Think something, quick!"
"I guess I just could add totally useless delay into the code."
"That, do that!"

Seriously, there's just no reason for that pause.

02-19-2014, 06:15 AM   #125
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Hi,
I'm sorry, my bad. As I found last night (as others suggested) it's the red-eye setting on my K-3 that created that "delay" on my AF 540.
I switched back and forth to confirmed it.
02-19-2014, 08:32 AM   #126
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QuoteOriginally posted by sinus007 Quote
I'm sorry, my bad
It's all good, not only did you find a solution for yourself, but by coming back to this forum to post what you found out, you are helping to keep the discussion from falling into a rabbit hole.
02-19-2014, 08:35 AM   #127
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Preflash is so difficult. About 1/3 of my subjects will blink with the pre-flash!
02-23-2014, 12:25 PM   #128
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I don't use P-TTL for People

QuoteOriginally posted by gosman Quote
Preflash is so difficult. About 1/3 of my subjects will blink with the pre-flash!
Each new technology has unintended consequences. You fix one issue, and introduce three new ones. Fortunately, Manual still works. I also have some flashes that use the old obsolete thyristor auto mode. Funny how the old technology works fine with no pre-flashes.

---------- Post added 02-23-14 at 11:34 AM ----------

I also have noticed a slight delay between pressing the button and anything happening when using P-TTL. It probably won't be a big issue for me since I probably won't use P-TTL for action shots of people much, but I am still curious as to what is causing the issue.

02-26-2014, 02:47 AM   #129
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More evidence

K-3 with Metz 52 AF-1 in P/TTL mode. No red-eye pre-flash. Pretty clear delay for me to move my finger so far! There is no delay in manual mode.

The response to my complaint from Australian Pentax distributors C R Kennedy was: "I have been advised by Pentax Japan that the flash is working normally. The K-3 has a new metering algorithm from previous cameras." Not very useful or promising.

02-26-2014, 09:09 AM   #130
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QuoteOriginally posted by Paul the Sunman Quote
K-3 with Metz 52 AF-1 in P/TTL mode. No red-eye pre-flash. Pretty clear delay for me to move my finger so far! There is no delay in manual mode.

The response to my complaint from Australian Pentax distributors C R Kennedy was: "I have been advised by Pentax Japan that the flash is working normally. The K-3 has a new metering algorithm from previous cameras." Not very useful or promising.

They are entirely correct that the flash is working normally, it's the camera that isn't.

New algorithm or not the algorithm only needs to start doing something after the preflash is fired.

I hope they fix it soon - even if it were not of any consequence it would still be a stain on a camera that is quick and snappy in everything else it does. It's a pity that record is marred by this one thing which makes it feel like a P&S from the turn of the century.
03-06-2014, 01:26 PM   #131
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Any change with 1.03?
03-07-2014, 12:05 AM   #132
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QuoteOriginally posted by Tjompen1968 Quote
Any change with 1.03?
No.
03-10-2014, 12:27 AM   #133
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This is also my K-3 biggest problem...
Hope RICOH fix the bug...
03-15-2014, 05:42 AM   #134
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Any news about?
This is the only reason why I'm stalling the purchase of K-3.
03-15-2014, 06:11 AM   #135
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QuoteOriginally posted by Vinfer Quote
Any news about?
This is the only reason why I'm stalling the purchase of K-3.
Not that I know of. Not fixed in the latest firmware release, and as far as I'm aware not even officially acknowledged by Ricoh/Pentax. It's only a problem though with P-TTL. Manual flash is fine. Unless you use P-TTL flash a lot, for subjects that move, I wouldn't let the issue delay your purchase of the K3. It's a brilliant camera.
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