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06-07-2015, 07:24 AM   #16
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Good to know, Lister. I'll try that with the Q or K-01. I take it you set the video at 30fps. My lag seemed to be close 1/3 of a second - or 9-10 frames worth. Now, it is hard to discern, but even 1/15th (2 frames) would be hard to detect, I suspect. The video test is a good way to make the determination. I'd be curious to know what kind of delay you get on the K-30 (I sold mine, but still have a K-01).

Imaging Resouce tested the various delays (early FW of course), and indicated pre-focus (non-flash) minimum is .096 - which would be under .3 frames; pTTL came in at .325 or 10-11 frames. Quite possibly what we are seeing is a significant reduction in lag, but not an elimination. Even the delay between pre-flash and exposure will cause reaction in people's faces - so my preference is not to use pTTL for people shots.

06-07-2015, 01:00 PM   #17
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I just did an update from 1.11 to 1.21 with (very unscientific) testing before and after - and can't see any difference at all. The on-board flash is all I have here, but the delay in p-TTL mode is definitely still there, and no shorter as far as I can tell.

My K-3 is of fairly early make, early 2014 at the latest.
06-07-2015, 03:15 PM   #18
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OK, I did the video testing - repeating the process several times in pTTL and M - all using the on-board. Used 30 fps on the K-01.

Lag to pre-flash - 4 or 5 frames, probably close to 4.5 frames, main flash follows in 2.5 frames or slightly less. Total time averages just under 7 frames, or 0.23. This is at least 1/10 of a second faster than in the past, but probably closer to .15 faster. I'm sure the lag was at least .35 seconds in the past. In any event, the exposures are about 90% correct; in the past it was about 40% blowouts when using wider apertures (less than 1/4th of flash power) when using the cheap external pTTL flash.

Frankly, manual flash does not have all that much less lag - averaging closer to 4 frames than 3 frames, so just barely less than the timing to pre-flash in pTTL. I would peg it at around .12 second. Of course, you don't have the lag between pre-flash and main exposure. I don't see where it is possible to know exactly when the shutter is fully depressed - even in pushing down rapidly. So, this is where the comparison of M flash and pTTL is most valid - and that difference appears to be at most .03 greater to pre-flash - almost non-existent.

The improvement isn't as great as my sense of the change, but clearly it is much closer to the acceptable range. More importantly, the flash output consistency is significantly better - at least based on the first several dozen test shots.
06-07-2015, 03:56 PM   #19
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No change for me. On board flash in auto has the delay. On board in manual does not. Had by daughters birthday party last week. It was a roller skating party so was quite dark, so needed flash to capture action. A lot of shots were missed because by the time the shot fired, the child had moved closer or further away and so shot was too bright or dark. Really disappointed. Should have taken my E-M10 instead. Smaller sensor and great glass, but flash is always spot on, and quick.

06-07-2015, 05:25 PM   #20
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QuoteOriginally posted by hastingd Quote
No change for me. On board flash in auto has the delay. On board in manual does not. Had by daughters birthday party last week. It was a roller skating party so was quite dark, so needed flash to capture action. A lot of shots were missed because by the time the shot fired, the child had moved closer or further away and so shot was too bright or dark. Really disappointed. Should have taken my E-M10 instead. Smaller sensor and great glass, but flash is always spot on, and quick.
No doubt, the mirrorless cameras are making strides. I don't doubt that the E-M10 provides consistent flash results. However, the IR scores on that body in flash mode are considerably slower than the K-3 - before the firmware update. If it was me, I would never try preflash TTL in a situation like a roller skating party - no matter which system. Auto-thyrister will be much quicker response and very consistent for that situation; and flash will recycle quickly depending on how much output is desired (ISO setting dependent). Personally, I would probably opt for high ISO (around 800) and really quick recycling so that multiple shots can be taken in succession.
06-10-2015, 02:11 PM   #21
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I updated my K-3 today. The lag is still noticeable. However, I believe that the lag is a tiny little bit shorter than before.
06-11-2015, 07:30 AM   #22
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1.21 no change to lag
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Last edited by awaldram; 06-11-2015 at 07:36 AM.
06-11-2015, 08:45 AM   #23
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Yes, clearly the lag has been reduced based on evidence

QuoteOriginally posted by awaldram Quote
1.21 no change to lag
What you're showing is main flash, not pre-flash, and nothing is timed. I could also raise my finger due to lag in M. As my repeated video timing research indicates, there is virtually no difference in lag between M and pTTL to pre-flash; previously the extra lag was significant. Nearly all the lag is related to the additional time between pre-flash to exposure. Nothing can resolve that failing until TTL is redesigned - such as the old system of single flash pulse and in-camera sensor.

It isn't a big deal to me because I'm going to avoid pTTL for most flash situations other than macro photography.

06-11-2015, 09:01 AM   #24
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QuoteOriginally posted by ScooterMaxi Jim Quote
What you're showing is main flash, not pre-flash, and nothing is timed. I could also raise my finger due to lag in M. As my repeated video timing research indicates, there is virtually no difference in lag between M and pTTL to pre-flash; previously the extra lag was significant. Nearly all the lag is related to the additional time between pre-flash to exposure. Nothing can resolve that failing until TTL is redesigned - such as the old system of single flash pulse and in-camera sensor.

It isn't a big deal to me because I'm going to avoid pTTL for most flash situations other than macro photography.
Mmm !! first is the same as I was doing on K3 (finger still on shutter) next is really pumping to get my finger off

So unless your saying the k3 has significantly more preflash - main delay than the Kx I think your wrong .... which it appears most respondeess are also finding 1.21 has no flash fixes in it unless there was a mech change and some k3's are fixed which I find unlikely given the delay is present in the k3ii. .
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06-11-2015, 09:19 AM   #25
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QuoteOriginally posted by ScooterMaxi Jim Quote
Nearly all the lag is related to the additional time between pre-flash to exposure. .
Not for me and others. My lag is between pressing the shutter and pre-flash. The time between pre-flash and main-flash is negligible on both P-TTL and Manual modes; nearly instantaneous.
06-11-2015, 11:29 AM   #26
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Enoeske, there is no such thing as pre-flash in Manual; it is non-existent not negligible.

Again, I actually tested it out - several times.

First of all, lag exists every time the shutter is released. Cameras that have less than .1 second will have no perceived lag by most of us. In fact, every Pentax camera has a lag of at least .08 in the very quickest of situations (prefocused, no flash), according to Imagining Resource.

Standing in front of a mirror proves pretty much nothing. Video or better yet some form of audio spectrogram are solid evidence. Repeated video frame measurements indicate that manual flash yields close to .12 second in manual, .14 second in pTTL to preflash, and a fairly consistent and easily measured .08-.09 additional between pre-flash and exposure (just under 3 frames). Hence, nearly all of the added lag is related to the duration between pTTL flashes. This is fact. Can I say for sure that my finger is activating at a precise frame? No. However, I can say - based on repeated tests - that the difference between manual flash and pTTL preflash is at .02 - virtually non-existent. This is testing, not just impressions.

Awaldram - you're right that the K-X has excellent performance - and the Imaging Resource testing confirms that. Still, lag is more than .08 prefocused, adding about .14 second in pTTL (this essentially confirms lag related to timing between flashes). In fact, my test of the K-3 matches the IR test of the K-X very closely. So, my measurements correlate with the IR testing. IR also shows that initial testing of the K-3 indicates that earlier firmware shows pTTL was .1 second slower - consistent with what I've estimated as a best-guess regarding improvement.

It would be nice if folks would post actual timed test results rather than impressions. What I found using timing was somewhat different than real-time, unmeasured perceptions.
06-11-2015, 12:51 PM   #27
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QuoteOriginally posted by enoeske Quote
Not for me and others. My lag is between pressing the shutter and pre-flash. The time between pre-flash and main-flash is negligible on both P-TTL and Manual modes; nearly instantaneous.
I'm not sure if this is what makes my K-3 seem to have very little shutter lag. I use back button focus rather than using the shutter release button to do everything.......just a thought.
06-11-2015, 01:00 PM   #28
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QuoteOriginally posted by Larrymc Quote
I'm not sure if this is what makes my K-3 seem to have very little shutter lag. I use back button focus rather than using the shutter release button to do everything.......just a thought.
I use the back button for focusing as well, but it can't release the shutter.
06-11-2015, 08:07 PM   #29
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QuoteOriginally posted by enoeske Quote
I use the back button for focusing as well, but it can't release the shutter.

I realize that but using the back button does eliminate a couple of operations that the camera has to go through when you use only the shutter button to take the photograph so its reasonable to assume that there should be less "shutter lag" even when using a strobe. I define "shutter lag" as being the time from when the shutter button is depressed to when the photo is actually taken. depressed could mean from half pressed to fully pressed or from not depressed to fully pressed.
06-11-2015, 09:46 PM   #30
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I use the back button. It is entirely possible that some portion of the lag previously observed came from using the shutter button for AF as well as shutter release. However, the only fair test then would have been to shoot in MF. Otherwise you're adding an unnecessary randomness to the process. The test has to be done uniformly with prefocus.

No one should be considering pTTL for any kind of action shooting. Clearly pre-flash is a huge detriment to accurate stop action.
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