[jco]

I just bought a second hand pentax K-5 IIs. Im having a problem using the built in flash. Im using a K lens, Manual mode.
The flash works fine at shutter speeds 1/40 or slower, but at faster speeds the resulting pictures are partially or fully out of
sync (black). Flash mode is set to flash ON. simple manual flash. Is the camera defective? What am I doing wrong? My istDS
doesn't behave like this under same settings and condtions, it syncs all the way to 1/180s.

[Adam]

I just bought a second hand pentax K-5 IIs. Im having a problem using the built in flash. Im using a K lens, Manual mode.
The flash works fine at shutter speeds 1/40 or slower, but at faster speeds the resulting pictures are partially or fully out of
sync (black). Flash mode is set to flash ON. simple manual flash. Is the camera defective? What am I doing wrong? My istDS
doesn't behave like this under same settings and condtions, it syncs all the way to 1/180s.

Many old flashes have a sync speed of 1/60s AFAIK. Also, the DS supports TTL, whereas the K-5 does not, which is why the exposure could be more consistent there. Just a guess!

[jco]

Many old flashes have a sync speed of 1/60s AFAIK. Also, the DS supports TTL, whereas the K-5 does not, which is why the exposure could be more consistent there. Just a guess!

Im not talking about using an old flash with the k-5 IIs, im talking about using its own BUILT IN FLASH.

[Adam]

Im not talking about using an old flash with the k-5 IIs, im talking about using its own BUILT IN FLASH.

Ah, missed that. Could still be related to the TTL, since on the K-5 your exposure is 100% manual. Maybe try a wider aperture?

Adam
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[jco]

Many old flashes have a sync speed of 1/60s AFAIK. Also, the DS supports TTL, whereas the K-5 does not, which is why the exposure could be more consistent there. Just a guess!

And secondly, I should make this clear, this is not an exposure problem, its a SYNC problem.

---------- Post added 07-27-2018 at 05:03 PM ----------

Ah, missed that. Could still be related to the TTL, since on the K-5 your exposure is 100% manual. Maybe try a wider aperture?

when you use a "K" lens, there is no TTL exposure or sync, the flash is supposed to fire full power manual at the rated sync speed of 1/180s regardless of lens aperture setting.

[Adam]

And secondly, I should make this clear, this is not an exposure problem, its a SYNC problem.

---------- Post added 07-27-2018 at 05:03 PM ----------



when you use a "K" lens, there is no TTL exposure or sync, the flash is supposed to fire full power manual at the rated sync speed of 1/180s regardless of lens aperture setting.

I *believe* that on the DS it will use the TTL sensor in the camera to measure the light in real time. This was removed on future bodies in favor of the P-TTL preflash approach.

I'm afraid that where my expertise with shooting with flash + manual lenses ends. Perhaps someone else can chime in so we can determine if it's a settings issue or an actual problem with the camera.

Are the resulting images consistent?

[jco]

According to the manuals for both cameras, the K-5 IIs and the istDS should both operate the same way with flash using K lenses and manual flash.

---------- Post added 07-27-2018 at 05:18 PM ----------

I *believe* that on the DS it will use the TTL sensor in the camera to measure the light in real time. This was removed on future bodies in favor of the P-TTL preflash approach.

I'm afraid that where my expertise with shooting with flash + manual lenses ends. Perhaps someone else can chime in so we can determine if it's a settings issue or an actual problem with the camera.

Are the resulting images consistent?

This is incorrect, with K lenses, both the K-5 IIs and the istDS do NOT measure or meter the light output from the flash, instead, the flash just fires FULL OUTPUT MANUAL and the correct exposure
can only be obtained be setting the aperture value on the lens correctly. The key is that ANY shutter speed 1/180s or slower can be used. Im having problem from 1/45 to 1/180

[UncleVanya]

According to the manuals for both cameras, the K-5 IIs and the istDS should both operate the same way with flash using K lenses and manual flash.

---------- Post added 07-27-2018 at 05:18 PM ----------



This is incorrect, with K lenses, both the K-5 IIs and the istDS do NOT measure or meter the light output from the flash, instead, the flash just fires FULL OUTPUT MANUAL and the correct exposure
can only be obtained be setting the aperture value on the lens correctly. The key is that ANY shutter speed 1/180s or slower can be used. Im having problem from 1/45 to 1/180

And this is ONLY in M mode? I don't have the K-5 does it have an X mode? I have often gotten frustrated with flash on my K-3 and just turned there to get the max shutter speed and manually adjusted everything else.

This isn't your problem but your settings for Tv steps can matter. Don't set it to 1/3 set it to 1/2 to get form 1/160 to 1/180. But again that's not your problem.

[enoeske]

I just bought a second hand pentax K-5 IIs. Im having a problem using the built in flash. Im using a K lens, Manual mode.
The flash works fine at shutter speeds 1/40 or slower, but at faster speeds the resulting pictures are partially or fully out of
sync (black). Flash mode is set to flash ON. simple manual flash. Is the camera defective? What am I doing wrong? My istDS
doesn't behave like this under same settings and condtions, it syncs all the way to 1/180s.

Can you post one of the black or partially black images with full exif data intact? Maybe a dropbox link?

[jco]

And this is ONLY in M mode? I don't have the K-5 does it have an X mode? I have often gotten frustrated with flash on my K-3 and just turned there to get the max shutter speed and manually adjusted everything else.

This isn't your problem but your settings for Tv steps can matter. Don't set it to 1/3 set it to 1/2 to get form 1/160 to 1/180. But again that's not your problem.

The K-5 IIs does have a X mode, where the speed is a constant 1/180s. I tried that too and the flash would not sync with a K lens, blank pictures on X mode.

[UncleVanya]

The K-5 IIs does have a X mode, where the speed is a constant 1/180s. I tried that too and the flash would not sync with a K lens, blank pictures on X mode.

OK - that's weird. Is this lens maybe painted or anodized? I'm clutching at straws here.

[jco]

OK - that's weird. Is this lens maybe painted or anodized? I'm clutching at straws here.

same lens syncs fine on an istDS

---------- Post added 07-27-2018 at 06:19 PM ----------

same lens syncs fine on an istDS

SMCK 28mm f3.5

---------- Post added 07-27-2018 at 06:21 PM ----------

Can you post one of the black or partially black images with full exif data intact? Maybe a dropbox link?

already boxed it up for return to seller. didn't save files

---------- Post added 07-27-2018 at 06:25 PM ----------

Does anyone here have extensive experience shooting with the on camera flash on the K-5iis with K lenses in M or X modes?

[mattt]

I shot plenty with K-5IIs + M / K series lenses.

As the pop up flash fired at full strength (it does not support TTL, just P-TTL) I only used flash photography with AF540 FGZ or AF360 FGZ in manual or A mode.

If you want to use the onboard flash with proper exposure you need at least A series lenses which communicate aperture to the body. With no aperture communication. You are expecting sync performance from an incompatible system.

---------- Post added 07-27-18 at 05:10 PM ----------

Just for kicks - if you still had the camera - I would make sure the flash settings in body were not set for second curtain. I would also try to rule out a shutter issue by doing tests in Hi speed continuous shooting through a full range of shutter speeds.

If you have boxed it up and shipped it back it’s a moot point.

[jco]

I shot plenty with K-5IIs + M / K series lenses.

As the pop up flash fired at full strength (it does not support TTL, just P-TTL) I only used flash photography with AF540 FGZ or AF360 FGZ in manual or A mode.

If you want to use the onboard flash with proper exposure you need at least A series lenses which communicate aperture to the body. With no aperture communication. You are expecting sync performance from an incompatible system.

---------- Post added 07-27-18 at 05:10 PM ----------

Just for kicks - if you still had the camera - I would make sure the flash settings in body were not set for second curtain. I would also try to rule out a shutter issue by doing tests in Hi speed continuous shooting through a full range of shutter speeds.

If you have boxed it up and shipped it back it’s a moot point.

are you saying you never used just the built in flash with k lenses at 1/180s?

[Adam]

For what it's worth, I just tested my K-50 with the M 50mm. The exposures were bright and consistent in M mode with the flash on, in both trailing curtain and regular sync, at 1/180s. F11 was needed for proper exposure for a subject about 3m away.


No reason why the K-5 wouldn't behave the same way, so I'm thinking sending it back may be the right call.