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02-02-2019, 04:13 AM   #1
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Flash issues on K-1 II

This is a dťjŗ vu issue for me with previous cameras, albeit the opposite way now. Under exposure using the FGZ-540 with bounce flash in Av mode with P-TTL. Essentially, the flash goes off but there is insufficient light from it during the exposure to register anything. It is as if the photo is taken at X-sync shutter speed that then leads to the underexposure, because the ISO is relatively low expecting the flashlight to fill the rest.

Only workaround is to hit the green button and let the camera set the ISO, which invariably goes up to fill in the exposure but again, very little light to see from the flash.

Anyone else experience this?

edit: the FGZ-540 has just stopped firing for the exposure (pre-flash still fires, but not the second flash for the exposure), but has fired for me previously.
Another flash I have fires but always at full-power (see below with the first set of photos in this thread).


Last edited by Ash; 02-03-2019 at 05:02 AM. Reason: changed circumstances
02-02-2019, 04:39 AM   #2
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QuoteOriginally posted by Ash Quote
This is a dťjŗ vu issue for me with previous cameras, albeit the opposite way now. Under exposure using the FGZ-540 with bounce flash in Av mode with P-TTL. Essentially, the flash goes off but there is insufficient light from it during the exposure to register anything. It is as if the photo is taken at X-sync shutter speed that then leads to the underexposure, because the ISO is relatively low expecting the flashlight to fill the rest.

Only workaround is to hit the green button and let the camera set the ISO, which invariably goes up to fill in the exposure but again, very little light to see from the flash.

Anyone else experience this?
Are you using auto ISO ? Best not to. Set a fixed ISO.

What is the flash to subject distance, including the bounce? it is possible it is too far, or your bounce surface is not reflective enough.

In Av mode the camera will use the flash as fill-flash if there is sufficient ambient light. Try manual exposure with P-TTL on the flash

Post some examples.

Last edited by pschlute; 02-02-2019 at 04:48 AM.
02-02-2019, 04:49 AM   #3
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Wasn't this a problem with earlier bodies and I think fixed in firmware? Maybe the "fix" got lost.

Other K-1/K-1ii and FGZ-540 owners would do a favor by testing this.
02-02-2019, 04:52 AM   #4
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QuoteOriginally posted by Ash Quote
It is as if the photo is taken at X-sync shutter speed that then leads to the underexposure, because the ISO is relatively low expecting the flashlight to fill the rest.
Whether the camera uses sync speed (1/180 or 1/200) or a lower speed will not affect the amount of light from the flash that illuminates the scene. What have you set aperture to and what ISO and shutter speed is the camera selecting.

02-02-2019, 04:56 AM   #5
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Underexposed images with bounce flash on K-1 II

Itís late tonight so Iíll have to post a photo tomorrow. I will endeavour to do this.

In the meantime, Iíll answer by saying the subject to camera distance is short, like 1.5m-2m with camera to ceiling distance about 1m. Shooting simple portraits. All the right conditions to shooting with flash. FEV 0 on camera and on flash. P-TTL with everything communicating with the camera okay. Whilst set on the ISO of my choice, it invariably leads to underexposure because the ISO is lower than the ambient light can supply for the subject. Flash doesnít fill. Then I hit the green button, and adjust the aperture and ISO thereafter, and suddenly the flash works. Iím missing something. But itís just not something Iíve noticed before on all my previous cameras.
02-02-2019, 04:58 AM   #6
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QuoteOriginally posted by Not a Number Quote
Wasn't this a problem with earlier bodies and I think fixed in firmware? Maybe the "fix" got lost.

Other K-1/K-1ii and FGZ-540 owners would do a favor by testing this.


I canít imagine why it would be happening to this camera. I have FW 1.02, the latest one.


02-02-2019, 05:01 AM   #7
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Underexposed images with bounce flash on K-1 II

QuoteOriginally posted by pschlute Quote
Whether the camera uses sync speed (1/180 or 1/200) or a lower speed will not affect the amount of light from the flash that illuminates the scene. What have you set aperture to and what ISO and shutter speed is the camera selecting.


I preferred ISO 200-400 indoors, aperture about 4-4.5 on the 31 Ltd for flash to significantly fill the subject. Without flash, ISO would have had to be jacked up to 6400 to adequately light up the subject. But thatís obviously not the intent of the photo.


It seems to reset itself after the green button, which means Iím finding a setting alter without my realising it.
02-02-2019, 05:03 AM   #8
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Ash, couple of things you can check: is the power output on the flash set to 1/1? Also both the camera and flash have compensation that can be set. Otherwise it could be distance/angle/reflectivity of the bounce.

(BTW my name is also Ash!)

02-02-2019, 05:04 AM   #9
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Interestingly, there hasnít been a problem with straight on axial flash the whole time. Just when bouncing. I have the first version of the 540 flash if that means anything.


02-02-2019, 05:12 AM   #10
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QuoteOriginally posted by Nunavut Quote
Ash, couple of things you can check: is the power output on the flash set to 1/1? Also both the camera and flash have compensation that can be set. Otherwise it could be distance/angle/reflectivity of the bounce.



(BTW my name is also Ash!)


Hey Ash! Yes definitely. All power is set to full but of course P-TTL mode overrides that. Everything else is set to neutral. Zero EC.


02-02-2019, 05:25 AM   #11
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As I have mentioned before, there are situations where the bounce flash works fine, manipulating aperture and ISO after hitting the green button usually fixes this. Then the next time I go and shoot after a power down or power off (seems to be after a lens change), then the problem recurs until the green button is again hit before then adjusting aperture and ISO. So it doesn't seem to be a fixed problem that FEC/camera EC would correct. I will have to demonstrate with photos tomorrow.
02-02-2019, 05:45 AM   #12
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QuoteOriginally posted by Ash Quote
aperture about 4-4.5 on the 31 Ltd
Aperture ring set to "A"
02-02-2019, 06:43 AM   #13
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Try setting ur camera in manual and flash in pttl. Say 1/200, f4, iso 200. The camera then let's the flash make the exposure. I find when the camera is in Av and flash pttl then there are two mechanisms trying to make the correct exposure and often it isn't right. I have k1ii and 540 flash as well. Good luck with it
02-02-2019, 08:03 AM   #14
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QuoteOriginally posted by Ash Quote
I canít imagine why it would be happening to this camera. I have FW 1.02, the latest one.
I've seen software fixes get "broken" again in subsequent releases. The fix isn't sufficiently documented and gets taken out in an update. Or you different teams working on releases and the base release one team is working off of doesn't get a fix the other team adds. It happens all the time in software development.
02-02-2019, 08:19 AM   #15
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Are you in X mode? Iirc the k3 would set the iso to 800 if i wasn't in X mode.

Last edited by derekkite; 02-02-2019 at 09:22 AM.
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