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01-21-2013, 04:45 AM   #76
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The flash issue exists on the K-30 as well. Check out my findings in this thread:
https://www.pentaxforums.com/forums/pentax-dslr-discussion/205191-fix-flash-e...es-pentax.html
I used to own a K-5, which i returned because of this.
My conclusion is that the amount of ambient light in the room has a big impact on the result.
Also, there is no overexposure when using liveview.

01-21-2013, 09:05 AM   #77
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QuoteOriginally posted by Lage Quote
The flash issue exists on the K-30 as well. Check out my findings in this thread:
https://www.pentaxforums.com/forums/pentax-dslr-discussion/205191-fix-flash-e...es-pentax.html
I used to own a K-5, which i returned because of this.
My conclusion is that the amount of ambient light in the room has a big impact on the result.
Also, there is no overexposure when using liveview.
Thanks for the input. Even though I searched the forums before, I keep being amazed to find yet more and more threads about the issue. This problem is so widespread and obvious it's very dissapointing Pentax still hasn't sorted it out.
BTW K-5II fw 1.01 doesn't solve the issue.

regarding your input about the K30 - It is a slightly different scenario than what I tested, as I tested manual exposure (M or X) and you used automatic exposure modes (Av or P etc.). I didn't read your thread deeply enough to correlate the results.

Could you test the flash in manual mode (as I did in this thread) and share your results? Please do it with and without LiveView. It will be very interesting to see what comes out of it.
01-21-2013, 12:39 PM   #78
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QuoteOriginally posted by Noam Quote
Thanks for the input. Even though I searched the forums before, I keep being amazed to find yet more and more threads about the issue. This problem is so widespread and obvious it's very dissapointing Pentax still hasn't sorted it out.
BTW K-5II fw 1.01 doesn't solve the issue.

regarding your input about the K30 - It is a slightly different scenario than what I tested, as I tested manual exposure (M or X) and you used automatic exposure modes (Av or P etc.). I didn't read your thread deeply enough to correlate the results.

Could you test the flash in manual mode (as I did in this thread) and share your results? Please do it with and without LiveView. It will be very interesting to see what comes out of it.
Unfortunatly not, I returned the K-30, so i only have the K100D Super att the moment, which works perfect with flash, bounced or not.
I would be interested to hear if your K-5II behaves similar to the K-30 regarding ambient light or not, LiveView or not.
02-01-2013, 06:35 AM   #79
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I just updated my k-5 iis to the newly released firmware 1.02. It has not fixed the tilt flash overexposure issue.

02-01-2013, 10:41 AM - 1 Like   #80
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My K-30 overexposes by about 1 stop when bounce is used with a Sigma EF-610 DG Super in P-TTL and K-30 M mode (and other modes). As I only ever use it for bounce it doesn't really matter to me, -1EV on the flash seems to work consistently enough for my needs. I don't know why flashes can't have separate EV compensations for direct and bounce.
02-07-2013, 03:26 PM   #81
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My K5 (v1.14) doesn't have this problem with my Metz 48 AF1 (v4.0). I even tried with my Nissin SC-01 universal shoe cord : no problem.

The room luminosity was : 9.6 Ev Temp. 21°C (PhotoMe Exif info), mix of led and fluorescent lamps.

Av mode, 1/80, F4, 80 ISO, -1.0 Ev compensation, no flash compensation neither on camera and flash, P-TTL mode.

Lens : Sigma 30mm F1.4 DC

Left column w/o Nissin SC-01 Right column with Nissin SC-01

First row : Direct
Second row : 45°
Third row : 90°

The raw shots were only converted to jpegs with PDCU4 and assembled with PhotoScape.

The ceiling, due to the age, is slightly yellow.

I have exactly the same result with F8.
Attached Images
 
02-08-2013, 08:31 AM   #82
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I have a Metz flash 58-AF1, and I observe similar problems with the K5 and PTTL. I actually use A mode for my flash or even manual as I find I get better results, and I was used to using A mode with an old flash that didn't have any type of TTL support. With the flash, compensation doesn't even seem to work. It's either over-exposed or under-exposed when I am bouncing with PTTL mode. Setting EV-1 for the flash or even the exposure just ends up with something that is too dark (looks like ambient).

I don't use flash much anyway, but it is annoying that you can't count on the modern feature to work. It's easier for me to just use the GN and calculate my distance, etc. with the bounce and flash than almost anything else. I can get the shot right on the first try or at least within 1/2 stop, which with a K5 is good enough.

My work around essentially involves having the flash set directly at the subject, horizontal, so I can see the distance meter. Adjusting the flash in manual mode so that the flash distance reads what my estimate is for the total distance the flash will travel (i.e. taking into account the flash moving up to the ceiling and then back down and across to the subject). You just have to be approximate, but it does help if you have a good sense of geometry and can estimate distances somewhat well.

For instance, if I am in a room with 10 ft ceilings, and I am taking the shot from around 5 ft height (tripod level for instance) and the target is 20 ft away. I'd try to manually adjust the flash to shoot a little less than 30 ft probably around 25 or so feet. (2 x 5 + 20) = 30 is the longest path your light would have to travel but with geometry, it would really go much less.

I know it's a bit lame, but it works if you can take the time. In a situation where you need to be quick, you either set the flash to something that will work on average or try to use the A mode (what I do). Thankfully, the K5 is low noise (and I assume the new K5's are too), so as long as you error on the side of under-exposure rather than blowing things out, you'll be ok.

It's sad to see on this thread that the K5ii(s) haven't fixed this problem. I won't bother buying one at any point since that would be the only improvement that would encourage me to upgrade from a regular K5.
02-08-2013, 11:54 AM   #83
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QuoteOriginally posted by emalvick Quote
I have a Metz flash 58-AF1, and I observe similar problems with the K5 and PTTL. I actually use A mode for my flash or even manual as I find I get better results, and I was used to using A mode with an old flash that didn't have any type of TTL support. With the flash, compensation doesn't even seem to work. It's either over-exposed or under-exposed when I am bouncing with PTTL mode. Setting EV-1 for the flash or even the exposure just ends up with something that is too dark (looks like ambient).

I don't use flash much anyway, but it is annoying that you can't count on the modern feature to work. It's easier for me to just use the GN and calculate my distance, etc. with the bounce and flash than almost anything else. I can get the shot right on the first try or at least within 1/2 stop, which with a K5 is good enough.

My work around essentially involves having the flash set directly at the subject, horizontal, so I can see the distance meter. Adjusting the flash in manual mode so that the flash distance reads what my estimate is for the total distance the flash will travel (i.e. taking into account the flash moving up to the ceiling and then back down and across to the subject). You just have to be approximate, but it does help if you have a good sense of geometry and can estimate distances somewhat well.

For instance, if I am in a room with 10 ft ceilings, and I am taking the shot from around 5 ft height (tripod level for instance) and the target is 20 ft away. I'd try to manually adjust the flash to shoot a little less than 30 ft probably around 25 or so feet. (2 x 5 + 20) = 30 is the longest path your light would have to travel but with geometry, it would really go much less.

I know it's a bit lame, but it works if you can take the time. In a situation where you need to be quick, you either set the flash to something that will work on average or try to use the A mode (what I do). Thankfully, the K5 is low noise (and I assume the new K5's are too), so as long as you error on the side of under-exposure rather than blowing things out, you'll be ok.

It's sad to see on this thread that the K5ii(s) haven't fixed this problem. I won't bother buying one at any point since that would be the only improvement that would encourage me to upgrade from a regular K5.
Did you update the camera firmware ?

02-11-2013, 05:37 AM   #84
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QuoteOriginally posted by fs999 Quote
My K5 (v1.14) doesn't have this problem with my Metz 48 AF1 (v4.0).
Lens : Sigma 30mm F1.4 DC
Quite interesting, because I have same setup (K-5 althouth on v1.13 fw, Metz 48 AF-1 and Sigma 30) and I always get the issue. I may upgrade the K-5 to 1.14 and check later.
02-11-2013, 10:27 AM   #85
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The problem still exists for me on Firmware 1.14 -- K-5 classic, Pentax AF360-FGZ flash, FA43 lens.

I tested at ISO400 f/4 1/100, I think, in Av mode (the camera selected the same exposure parameters for both shots), at a subject distance of about 1 meter, and the ceiling about 2 meters above the camera. Results are consistent with what I saw before, namely, perfect exposure with direct on-camera flash, and overexposure by about 1.5 stops with the flash bounced.

It's really odd that some people see this problem and others don't. I have noticed the same thing about K-5 low-light focus issues -- some people are driven crazy by this, but others are quite satisfied.

It's almost as if there are two slightly different batches of K-5's out there.
02-11-2013, 11:54 AM   #86
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I tried at 400 iso same result.

PentaxVersion is 70.0
Make date is 2011-01-22
Service Nr (CameraInfo[2]) is 2
Production ID (CameraInfo[3]) is 1
02-13-2013, 01:41 AM   #87
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Hello...

Just to throw some more oil unto the fire, I've made my own set of tests...
I wanted to see if the lens aperture had an effect. After all, metering is done with the lens wide open, and that would also explain the different behaviors we see depending on the user : each of us has its own set of lenses so they surely have an impact...

OK, so here is what I've done : I've used only one lens (a PK-m Porst 135/1.8), but with the aluminum foil and halfway mount tricks to fool the camera so it thinks it always has a PK-A f/1.2 lens used at f/1.2, whereas the actual aperture varies (so I can actually choose what is the "wide open" aperture).

These tests were made using a EE-S screen.

First, straight flash: results are perfect from f/1.8 down to f/16 (with a slight variation, but you really have to look for it, I'd say maybe half a stop)... So, using an EE-S and any lens, you'll always get the same direct flash exposure (I'd suspect that using the stock screen would result in a -1 Ev variation with fast lenses, just like with stop-down metering).

Now, with bounce flash, results are really strange...
First, in my test conditions, between f/1.8 and f/2.8, exposure is good, with no visible variation...
Then, at f/4, a major overexposure occurs, followed by a seemingly constant flash power from f/4 down to f/16 (each pic being gradually darker than the previous one thanks to the decreasing aperture)... What is crazy is that the camera has no way to know that it reached f/4!!! So why the sudden overexposure? We already determined from the straight flash test that the focus screen gives accurate readings on the whole aperture range!

I'll go on with my tests, but it seems to me that in bounce mode, below a certain pre-flash metering reading, the camera loses its mind and fires the flash at a fixed output...

That would explain why some persons experience the problem, and others do not... For instance, I often use fast lenses only (between f/1.4 and f/2.8) at moderate distances, and so the pre-flash metering certainly stays above this threshold, and P-TTL works for me... But take someone using slower lenses, on longer distances, right at the edge of this threshold value... One moment the picture would be fine, then it would overexpose (or underexpose) for no reason, the flash being fired at this fixed level...

Now, the only time where I had trouble with bounced P-TTL and had to switch to manual was while snapping candid pics from afar in a dark venue, bouncing against the ceiling. Thinking back to this moment, I recall that I was baffled by the P-TTL behavior: it felt like it was indeed firing at a fixed power, as changing the iso was having a direct effect on flash exposure, even while I was far from the flash' maximum power and flash exposure compensation was useless (and switching to manual flash solved the problem anyway, so P-TTL should have handled it).
03-04-2013, 10:12 PM   #88
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I started this discussion back in 2011 writing about my experience and findings with K7 overexposure with bounce PTTL flash. See K5 bounce flash overexposure - mystery solved! MUST READ!: Pentax SLR Talk Forum: Digital Photography Review and similar threads. I have since disappeared from all Pentax forums for over a year and I am both surprised and also felt relief to discover more people who own the latest models are also experiencing this issue. This shows the resolute of Ricoh-Pentax to bury its head in the sand to the protest of its customers and a long-suffering Pentax populace. I do not think we as consumers have stood up to our rights and demand Ricoh-Pentax takes firm and prompt actions to resolve this issue and vote with our feet if Pentax fails to bow to pressure. Instead we as a community have chosen to use our ingenuity to develop workarounds and band-aid fixes to solve a problem that rightly belongs to the manufacturer. I cannot imagine Canonians or Nikonians would be so kind and patient if a problem of similar nature or magnitude happen to their equipment.

David
03-05-2013, 02:47 AM   #89
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not all... that's the problem...
03-05-2013, 04:50 AM   #90
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I agree with fs999, not everyone have this issue. My K5 with Metz 48 AF1 exposes better than using direct flash, I don't know the reason but using direct flash with Pentax 17-70 I need to set -0.7 compensation while bounced flash it's ok without any compensation.
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