[JimJohnson]

The communication is through a modulated light pulse from the controller (on the camera) to the slaves. The control pulse has a signature specific to the set channel. The slaves must be able to "see" the controller light pulse (either direct or reflected) in order for the wireless sync and control to work.

To be specific, the signal embedded in the pre-flash is in the IR frequency range. You can place an IR filter over the flash to block all visible light and still trigger the slave P-TTL flash(es). IR is considered to be at the bottom of the light spectrum (because humans cannot perceive it) and the top of the RF spectrum (although like light, it is line of sight but reflects off objects).

There are inexpensive visible light shields that sit in the hotshoe and hang over the popup flash on Pentax, Canon, Nikon, ... cameras. I have one and it works quite well. AND goes to show that ALL the major camera makers used their popup flash in much the same way to control compatible off-camera flashes. The only real difference is each manufacturer has its own signal encoded within the IR pulse.

[Smoke665]

Steve

* The communication is through a modulated light pulse from the controller (on the camera) to the slaves. The control pulse has a signature specific to the set channel. The slaves must be able to "see" the controller light pulse (either direct or reflected) in order for the wireless sync and control to work.

I thought I was done with posting on this thread but your in depth on-topic responses drew me back in. Thank you for the clarifications and confirmations I appreciate those responses.

As to the off-topic comments on the modulated IR control of off camera speedlights, we are both right. I've been aware of the use of IR all the way back to the introduction of the thyristor flash control back in the early 70's (yes I predate that), but was curious to see if anyone else was aware that there are options available. Probably should have approached it differently. I rarely use P-TTL, or for that matter off camera speedlights, preferring radio trigger manual monolights. I only have one out of several speedlights that I think is even compatible with Pentax, P-TTL, maybe I need to experiment with it.

In any case, I would suggest all to read up on "Non-Flash-Emitting Triggering Devices". If you don’t use a flash to trigger the remote strobes, you can use a TTL-flash-compatible wireless trigger, or “transmitter,” seated in the camera’s hot shoe. This can be an optical/infrared or Radio Frequency (RF, or simply radio) system. Radio systems are the best choice under conditions that are less than optimal for optical systems. If you've ever had optically controlled speedlights fire in your face unexpectedly or not fire because of line of sight obstacles, you'll know what I'm talking about. Radio signals can reach distances of several hundred feet, which gives them an advantage when the remote speedlights are positioned outside the range for a typical optical device. Radio signals easily circumvent most obstacles, so speedlights attached to radio receivers can be hidden away and still fire as needed. This becomes more important as you start adding groups of multiple flashes. There are also "hybrid" triggers which use both radio and IR signals. Some of the newer speedlights include a 2.4GHz transmitter that have the option of two way digital communication with remote flashes or optical control (for backward compatibility). As I said rarely use P-TTL so I haven't had the need to determine the compatibility of these devices with Pentax, in a true P-TTL application, but the literature on several claim to be compatible in a wholly digital manner. I know there are several others out there, including I believe, the low end Yongnu (though I haven't verified that) but here's a couple of examples to start.

Catcus V6 - The 2.4 Ghz V6 transceiver comes with a multi-system shoe that supports TTL pass through. With TTL pass-through, the TTL flashes behave as they would when directly connected to the camera hot shoe with Canon, Nikon, Olympus, Panasonic, Pentax, and Fujifilm via one single unit; Cactus Wireless Flash Transceiver V6 | CACTUS

Metz M400- 2.4 Ghz flash. TTL flash mode (digital only), Pentax, P-TTL flash mode and P-TTL remote operation. Ausstattung: Metz


Perhaps someone who's actually had operation experience with digital P-TTL communication (rather than the speculative comments herein by all) can speak up on the subject.

[JimJohnson]

My issue is a finite and when I fly, very small, space for transporting photographic gear. The popup flash is there (I deliberately went K-3 rather than K-3ii), takes up no more space or need to keep track of. Sometimes it is the only flash I can take. Further it actually works quite well for fill and catch-light when paired with an off camera flash. In a studio situation, or the ability to transport gear to setup a studio situation, I can see (have seen*) where RF flash triggers are a great idea. In my circumstance I cannot justify the expense in relation to the amount of use.

* I drool over the RF flash system installed at the local University's ice arena. The entire ice surface is uniformly covered by flash lighting. The official photographer can shoot manual with both a lower ISO and smaller aperture and know exposure will be perfect with the flash duration acting as the exposure time.

For what it is worth, I do understand both RF and digital communications - I am a licensed amatuer radio operator who works professionally in the high tech industry.

[Smoke665]

My issue is a finite and when I fly, very small, space for transporting photographic gear.

Fully understand this, the K3II even with a smallish camera mounted flash is a top heavy pain in the rear. Especially in crowds.

I do understand both RF and digital communications

Any chance you might elaborate more on the Ice Rink lighting??? Is it actually a TTL type setup?? Equipment???

[stevebrot]

Perhaps someone who's actually had operation experience with digital P-TTL communication (rather than the speculative comments herein by all) can speak up on the subject.

Does actually using the gear count? There are numerous extensive threads on the lighting/flash section of this site that discuss multiple options for mixing matching available triggers, studio lighting, speedlights, and Pentax-compatible flashes to work with Pentax-brand cameras.

Flashes, Lighting, and Studio - PentaxForums.com

At this point, I have to confess to being somewhat puzzled. Your initial post (quoted below)...

Flash Setting On K3 II
Using off camera flashes (not TTL) what should my camera flash setting be?

...indicated inexperience with the camera and off-camera flash. Accurate answers were provided. In subsequent comments, you claim deep experience and full understanding of a wide variety of gear and technologies including Pentax P-TTL and a good selection of trigger options. With camera and manuals in hand, configuring non-TTL off-camera flash on the K-3II should have been easy. Your post history indicates that you had a K-30 before purchase of the K-3II. What worked on the K-30 should work with the K-3II.

Assuming that is not the case and given that remote P-TTL is a red herring, perhaps it would be helpful if you could list the gear you are trying to work with and indicate what is not working for you in configuring fully manual remote flash to work with your K-3II.


Steve

[JimJohnson]

Any chance you might elaborate more on the Ice Rink lighting??? Is it actually a TTL type setup?? Equipment???

The rink setup is camera agnostic, all exposure is manual. Set flash sync speed, and set aperture/ISO for the right EV and mount the radio trigger. The smaller the aperture, the less ambient light comes into play and conversely the effective shutter speed becomes closer to the flash duration.

The flash units and radio receivers are permanently mounted and calibrated to uniformly light the entire ice surface. That's why the official photographer can set the EV and forget about it. All she/he needs to worry about is framing, focus and timing (which is plenty). It doesn't matter where in the arena the photographer is located.

Of course the only photographers who can access the system are those with the right transmitter with the right settings.

Simple in concept and use, but pretty complex in cost and effort to install.

[Smoke665]

At this point, I have to confess to being somewhat puzzled. Your initial post (quoted below)...

I've had several Pentax models dating back to the old Spotmatic, as well as multiple Canon models.My question wasn't one of inexperience but of confirmation I wasn't missing something on the settings, because of the nature of the K3II manual. My OP was answered to my satisfaction in post #13, three days ago, which with this post I have now acknowledged multiple times. As to any other supplemental questions from that OP not answered, I think I've already acknowledged that you answered or confirmed my understanding on them and thanked you for your response. On the off topic comments by others and unfortunately myself, I've suggested that another thread be opened by anyone wanting to continue those topics, or as an alternative, I've suggested someone with real life experience comment on them. If you have real life experience with using RF and P-TTL then by all means please share those experiences with some specific equipment models, situations, results, etc. here, on another thread (please tag me as I'd like to follow it), or if you have a specific previous thread on the use of RF as it applies to the Pentax P-TTL system, then please share that. I'm not sure that I would shift to P-TTL, but I'd look at an RF option. What exactly is confusing about any of these statements?

Edit update: I did in fact review the link you suggested, and found that one of the suggestions made earlier the Cactus V6 apparently doesn't work as advertised with Pentax. Unfortunately I did not find any concise in depth discussions on what actually does work with Pentax.

---------- Post added 12-07-16 at 01:18 PM ----------

all exposure is manual

Bummer I was really hoping you were going to tell us they use P-TTL. Still, someone put a lot of thought into lighting a large area like that.

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Last edited by Smoke665; 12-07-2016 at 12:48 PM. Reason: added update

[mcgregni]

It was always going to be difficult to work out exactly what this thread was all about, but my own guess early on was that the question was about the flash mode options on the K3II, based on that minimalist opening post. As at the time I was writing up the section of my Flash Guide Supplement about the new camera models without the built -in flash, and this included of course a detailed look at the flash modes and how they differ from the modes on the other models with a flash. So that is why I got involved and commented on the modes .....kind of wish I hadn't bothered now, but we are where we are .....

There are only 2 main choices on the K3II, 'Auto Flash' and 'On'. According to the manual the Auto mode (which uses the metering system to decide whether or not to fire the flash) depends on having a dedicated system flash mounted ..... There's no effect with a manual flash or radio trigger, so with that type of equipment then the flash mode should not matter at all. As was said by Adam early on also, the trigger signal is sent to the hot show (up to the max sync speed) regardless with basic equipment on the hotshoe.

[Adam]

Thread closed upon request.