[devorama]

So there are really two confusing issues you are illustrating here.

First, why does the K-5 flash still show up illuminated when set to controller mode in a wireless p-ttl setup? I've found that regardless of that setting (controller or master), you will always get SOME illumination from the built in flash in the photo. It will be much less in Controller mode, but still there. If you truly need no illumination from the K-5 flash, you'd be better off with a radio trigger or flash cord. But if you must use optical wireless p-ttl, you could try to block the visible portion of the K-5 flash with an IR pass filter or use a developed piece of 35mm film header. That will let the invisible ir portion of the flash to pass through and still activate the Sigma, but it should be pretty invisible to the K-5.

The second confusion is with non-pttl wireless. You cannot activate the sigma in this mode with the built in K-5 flash and get a good result. That's because you cannot turn off the K-5 pre- flash. So the Sigma will always fire early. You would need to activate it with a dumb, non-pttl shoe mounted flash. This is a possible improvement for the K-5. It should allow us to manually set flash output while suppressing the pre-flash it uses to judge exposure. My Olympus XZ-1 can do this. But currently, the K-5 can't do this.

[chromo]

Ah right....I never thought about the K-5 still doing pre-flash in standard mode.

So to use optical slave I would be better off to put my Pentax AF 160 on the camera. It has 2 pins so I presume the second pin is only to tell the camera when the flash is ready. Is this correct ?

I do intend to buy 2 or 3 YN-560's, So I could use one of these on the camera for those times when I want more light from the camera and in optical slave mode ??

I will be buying a set of wireless triggers can't make up my mind which type yet. Maybe the RF-602 or iShoot PT-04G. The YN-04's don't have enough distance capability for me.

The main idea of doing these flash tests is not only learning how to use them and check that they work properly, but by utilizing the onboard flash is an extra flash I don't have to buy.

You'll notice the 1st test I did here contradicted part of the 1st post that I wrote, yet if I don't want the onboard flash to contribute to the exposure is confusing as would have thought that any preflash would happen before the shutter opens. Sounds logical to me.
I realize now that I'm going to have to sit down and read the flash manual about 5 times and try to understand it. I sure hope the confusion goes away.


My wife was not happy that I showed the rest of the world the dust on that mirror.


One more thing, Is it safe to put that AF 160 on my K-5 ? and are the YN-560's safe too ?


Any more comments will be appreciated.

[SOldBear]

I never thought about the K-5 still doing pre-flash in standard mode.

The only way for Pentax DSLRs' built-in flash NOT to fire a pre-flash strobe is to use a manual lens. In this case, the built-in flash fires one strobe at full power. If you plan to use optical slaves, the slaves have to either support p-TTL mode, or be able to ignore the preflash strobe. There are some optical slaves that can ignore the preflash strobe. But RF remote trigger is much more convenient.

As you mentioned, a way to get around this is to use an external flash in non p-TTL mode, attached to the camera's hotshoe.

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Edited to add:

Is it safe to put that AF 160 on my K-5 ? and are the YN-560's safe too ?

I know the AF160 is safe, using one myself. I think the YN-560 is safe.

About trigger voltage, you should learn how to measure it. A flash model may have many versions, with different trigger voltage.

[chromo]

Sorry SOldBear, I was still editing my last post when you answered.

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Last edited by chromo; 12-30-2011 at 02:59 PM.

[dosdan]

Here's an example of the EF-530 DG Super off-camera, being triggered by the on-camera flash on a K20D:

https://www.pentaxforums.com/forums/accessory-memory-articles/95124-ext-flash...int-flash.html

Haven't tried this with the K-5 yet.

Dan.

[Usuqa]

You are not doing anything wrong, sadly the k5 fires quite a strong flash when using wireless p-ttl (unlike the k10d) and can easily become part of your photo when you just want it to act as a controller.

To get around this I sometimes just bounce the flash with a white card if indoors, this will weaken the flash a lot but should still trigger your other p-ttl wireless flash's. Or you can buy the Nikon Nikon SG-3IR adaptor to cover the flash to only allow the IR frequencies through to trigger the flash, this way no light from the flash should bleed into your shot.

While p-ttl is handy, and on occasions has been great for me.. If I want to do any sort of creative off camera flash stuff I use radio triggers and manual flash's.. much more reliable (trigger over greater distance, no line of sight problems) and because the flash's are in manual much easier to turn up/down to get the desired results.

I can use the C0 mode at times though when using my other flashs with radio triggers (as I only have three triggers) to let the sigma become part of my setup and it works great there (no pre-flash), unlike my metz af50-1 which is a great flash but will has no setting like C0 on the sigma.. although it has a dumb mode that ignores pre flash. I wish both the sigma and metz had both versions of the dumb flash (use/ignore pre flash.)

[audiobomber]

You are not doing anything wrong, sadly the k5 fires quite a strong flash when using wireless p-ttl (unlike the k10d) and can easily become part of your photo when you just want it to act as a controller.

That's what I've heard. In Wireless Controller mode, the K10D and K20D fire a weak signal that does not contribute to flash fill. (I have confirmed this with my K20D). The K7 and K5 fire a stronger signal that may, depending on conditions, add fill. I saw this demonstrated at the other site using a K5. The reason for the stronger signal in the newer cameras is to increase the range of conditions for using off-camera flash; i.e. brighter signal flash allows better communication with off-camera flash in strong ambient light and an increased working distance.

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Last edited by audiobomber; 12-31-2011 at 02:43 PM.

[mattdm]

You are not doing anything wrong, sadly the k5 fires quite a strong flash when using wireless p-ttl (unlike the k10d) and can easily become part of your photo when you just want it to act as a controller.

To get around this I sometimes just bounce the flash with a white card if indoors, this will weaken the flash a lot but should still trigger your other p-ttl wireless flash's. Or you can buy the Nikon Nikon SG-3IR adaptor to cover the flash to only allow the IR frequencies through to trigger the flash, this way no light from the flash should bleed into your shot.

Or DIY: https://www.pentaxforums.com/forums/1761206-post9.html