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12-19-2012, 04:11 PM   #46
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QuoteOriginally posted by Quicksand Quote
Noam,

Your contributions here are very valuable. I appreciate the effort you have put into testing.

Unfortunately, your results are entirely, 100% consistent with my observations using a K-5 "classic" and a Pentax AF360 flash. They are precisely what I see.

I have hammered on this a number of times in prior posts over the last year or more, and I see you are now receiving some of the same objections:
Maybe you are trying to operate the flash outside of design parameters, too close, ISO wrong, or whatever. NO. The direct flash almost always exposes correctly. In edge cases, bounce flash should underexpose if anything.

Maybe it's operator error. NO. My old K20d could handle this no problem.

You can work around the problem by dialing in negative flash exposure compensation, or whatever. NO. This is P-TTL, it's supposed to figure this out by itself!
It's a bug. It's clearly a bug, and I have said so repeatedly. It works fine in direct flash mode. It works fine wirelessly. It's only the combination of external flash, on-camera, bounced that results in overexposure.

I am TREMENDOUSLY disappointed to learn that this is still a problem on the new models. I'm losing hope for a fix. I have basically given up on bounce flash at this point, and in cases where I really need it, I either go with full-manual settings, or take the flash off the camera and use wireless P-TTL.

Some of my prior posts on the subject:

https://www.pentaxforums.com/forums/pentax-k-5/200387-k-5-pttl-bounce-flash-a...ml#post2116767

https://www.pentaxforums.com/forums/pentax-k-5/191116-some-insight-into-flash...ml#post2027171

https://www.pentaxforums.com/forums/pentax-k-5/171474-firmware-v1-12-23-20-a-4.html#post1780208
Couldn't have put it better myself. The linked discussions really cover the tests we all did a while back. It's a huge disappointment this is still occurring with the K5II. I spent ages trying different tests - in short, on shoe bounce flash is prone to significant overexposure with K5/AF360 and K5/AF540. That said, I just try to get on with my life and use FEC of -1.5ish in the circumstances where it is likely to happen.

12-20-2012, 11:45 AM   #47
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QuoteOriginally posted by JinDesu Quote
What about doing it in Liveview mode? Especially with the k-30, as it shares quite a bit with the k-01.
Metering is still done by the metering inside the camera, not from the "image" as far as i know.
12-20-2012, 03:29 PM - 1 Like   #48
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I remember there were reports of over-exposure in bounce position of some Metz flashes without using pTTL, just the A setting of the flash. I wasn't able to reproduce these effects, at least on a regular base, but other members of this forum could.
They found out that there was no malfunction if, after switching the flash to bounce, they once recalled the flash program (profile) that they already were using. So it seems this problem is/was related to the flash firmware or to the camera/flash interaction, and not to the camera itself.

EDIT:
You can find one of the threads if you start with post #26 (edited!) of https://www.pentaxforums.com/forums/pentax-flashes-lighting-technique/176988-...er-advice.html
I think there were some even older threads about this subject, too.

You may also have a look at http://forums.dpreview.com/forums/post/23002010

Last edited by RKKS08; 12-20-2012 at 03:43 PM.
12-21-2012, 01:10 AM   #49
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QuoteOriginally posted by RKKS08 Quote
I remember there were reports of over-exposure in bounce position of some Metz flashes without using pTTL, just the A setting of the flash. I wasn't able to reproduce these effects, at least on a regular base, but other members of this forum could.
They found out that there was no malfunction if, after switching the flash to bounce, they once recalled the flash program (profile) that they already were using. So it seems this problem is/was related to the flash firmware or to the camera/flash interaction, and not to the camera itself.

EDIT:
You can find one of the threads if you start with post #26 (edited!) of https://www.pentaxforums.com/forums/pentax-flashes-lighting-technique/176988-...er-advice.html
I think there were some even older threads about this subject, too.

You may also have a look at Problems with Smart Auto Flash - Metz MZ40-x and K10D: Pentax SLR Talk Forum: Digital Photography Review
RKKS08 thanks for the link.
It seems to me like another issue with somewhat similar symptoms (overexposure). It relates to usage of Metz modular flashes + PTTL adapter that suffer from the bug, regardless of Pentax DSLR model (i.e. all models). The problem discussed here is with native (PTTL) system flashes in combination with K-7 and K-5 variants only. Anyway, native PTTL flashes have no "profile" or "program" to set or reset, so unfortunately the fix with the Metz 40 and 54 flashes doesn't apply here.

Thanks anyway. This information could still be useful to the engineers trying to diagnose and fix the bug (yeah right...).

12-21-2012, 10:12 PM   #50
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What's the difference between bouncing and diffusing the light? I tried bounce 31 years ago and never did it again.
12-21-2012, 11:13 PM   #51
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QuoteOriginally posted by tabl10s Quote
What's the difference between bouncing and diffusing the light? I tried bounce 31 years ago and never did it again.
I bounce and diffuse with a Demb attachment. The idea of bounce is that most of the light in the world comes from above, whether it is sky, sun, or ceiling lights. Bouncing with a bit of forward fill looks more natural and is far less harsh than direct flash, including direct flash that is diffused.

Some other benefits are:

Bounce fills shadows behind the subject so you do not get that harsh dark cave shadow look.

Bounce can be directed off a wall or different points so that you get light from above and from one side or another which adds modeling to faces, reducing the flat one-dimensional look of on-camera flash.

Ray
12-22-2012, 01:50 PM   #52
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QuoteOriginally posted by johnc Quote
Couldn't have put it better myself. The linked discussions really cover the tests we all did a while back. It's a huge disappointment this is still occurring with the K5II. I spent ages trying different tests - in short, on shoe bounce flash is prone to significant overexposure with K5/AF360 and K5/AF540. That said, I just try to get on with my life and use FEC of -1.5ish in the circumstances where it is likely to happen.
I think what Pentax have done is use distance data in the flah exposure solution on the K5 so works perfectly for direct flash but as your probably aware lift up the flash head and what happens to distance data? ...thats righ it goe to null (no reading) so the algorythm fails and over exposure occurs.

My solution is to always use a contoller flash point forward, all bounce done from remote slaves work great flash is very consistent and accurate.

But agree Pentax shoudl get a grip and fix this issue along with the other flash fxck ups they introduced in the K5

i,e delay and wirelss P-tll (give it a try it'll make you laugh at the logic error)
01-01-2013, 02:16 PM   #53
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I reported this on the Firmware update thread, but repeating it here is probably more relevant. I just ran some tests on this longstanding tilt flash overexposure issue using my K-5 / AF540FGZ to see if the recent silent firmware update might have some improvements (it did not). Using a tripod and focused at a relatively neutral scene, I get perfect exposure with direct flash, and 1-2 stops overexposure the moment the flash is tilted in any direction. This behavior is exactly the same with my new K-5 iis. Interestingly, I have now noticed that the overexposure is triggered at the same moment that the tilt icon appears on the flash rear LCD screen. It is possible to tilt the flash a little way before the icon is activated, and the exposure remains fine. Just a tiny bit more tilt, activating the screen icon, is then coupled to the overexposure. With the behavior so clearly linked to an electronic trigger (which is also activating the tilt icon on the flash LCD screen), one would think this long standing problem could be easily corrected in the FW.

01-01-2013, 10:09 PM   #54
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QuoteOriginally posted by bjdavey Quote
I reported this on the Firmware update thread, but repeating it here is probably more relevant. I just ran some tests on this longstanding tilt flash overexposure issue using my K-5 / AF540FGZ to see if the recent silent firmware update might have some improvements (it did not). Using a tripod and focused at a relatively neutral scene, I get perfect exposure with direct flash, and 1-2 stops overexposure the moment the flash is tilted in any direction. This behavior is exactly the same with my new K-5 iis. Interestingly, I have now noticed that the overexposure is triggered at the same moment that the tilt icon appears on the flash rear LCD screen. It is possible to tilt the flash a little way before the icon is activated, and the exposure remains fine. Just a tiny bit more tilt, activating the screen icon, is then coupled to the overexposure. With the behavior so clearly linked to an electronic trigger (which is also activating the tilt icon on the flash LCD screen), one would think this long standing problem could be easily corrected in the FW.
Exactly. My test revealed the same dependency on the "tilt icon" state. It is clearly a FW bug.

EDIT: More precisely, it depends on the appearance of a distance scale on the flash LCD. When my flash is tilted down (slightly, for macro shots), the tilt icon appears yet the distance scale is still there, and the exposure is the same as straight (i.e., not overexposed).

So, the bug affects any P-TTL flash (including Pentax) in combination with a K-7, K-5 or K-5II (s). That's three product generations!

EDIT: First indication (posted further below) that the K-01 is possibly affected as well. Guys, please back your findings with controlled test shots (tripod, all settings equal, one shot straight one tilted) and share!

Is there any member here with some connection to Pentax/Ricoh (dealers, support, sales, management, territories, whatnot)? This information needs to travel a long way to the R&D team in Japan...

Last edited by Noam; 01-05-2013 at 12:22 AM.
01-04-2013, 03:54 PM   #55
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How many stops overexposure are we talking about? I just tried P-TTL bounce for the first time and compared it to bounce in "A" and found the P-TTL more pleasing/vibrant. I guess I'll try again with different subjects..

Last edited by tabl10s; 01-04-2013 at 04:27 PM.
01-04-2013, 04:13 PM   #56
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The best way to avoid most of this is to use a flash with an auto mode built in. The metz certainly give very accurate readings. I once measured the accuracy of my hammerhead metz with my seconic light meter. I found it to be spot on. The worst was at F16 where it was one third of a stop under. Of course it used to be the norm. These days it seems it is only implemented on top range units. So if PTTL is not reliable... bypass it altogether. I am sure there are lots doing it already.
01-04-2013, 04:29 PM - 1 Like   #57
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I'll go P-TTL and "A" for bounce.
01-04-2013, 05:20 PM - 1 Like   #58
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QuoteOriginally posted by tabl10s Quote
How many stops overexposure are we talking about?
In my case, about 1.5 - 2 stops. See pics below

First pic is direct flash (normal exposure), then upward flash tilt to point just before tilt icon appears on flash LCD screen (still normal exposure), then a fraction more tilt to activate the flash LCD tilt icon (overexposure)
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01-04-2013, 06:07 PM   #59
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Until they fix this, perhaps an investment in a TTL cord? Yeah, it's probably the worst possible work-around, but if you hand tilt the flash without using the tilt/swivel head, you can get proper exposure and bounce at the same time.

I died a little inside just typing that.
01-04-2013, 11:52 PM   #60
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QuoteOriginally posted by tzeentchiangod Quote
Until they fix this, perhaps an investment in a TTL cord? Yeah, it's probably the worst possible work-around, but if you hand tilt the flash without using the tilt/swivel head, you can get proper exposure and bounce at the same time.

I died a little inside just typing that.
I'd call that the second-worst workaround. The worst being using optical wireless slave mode, with the flash eight inches away in my left hand, just to get well-exposed bounce.

And yeah, I have done that.
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