[Class A]

1) So the flash needs to be set in HSS PTTL mode?

Yes.
This is just to allow the V6II receiver to make power level (and zoom setting) adjustments.
Power level control is still manual.

2) How seamless is moving from shooting at 1/180 to 1/250?

I haven't made any measurements yet, but from memory such a jump in shutter speeds resulted in a plausible result, i.e. no jarring differences in flash exposure.

Does the trigger or flash need to be set differently to work in normal mode vs. HSS?

No, there is a "Normal HSS" mode that will use standard flash for slower shutter speeds and HSS when shutter speeds exceed the sync speed.

I guess my main thought is, if I am in AV mode and if I have the flash at ¼ power at 1/180, and then my shutter speed jumps to 1/250th, because the flash now needs to function in the pulsing HSS mode, does ¼ power throw out a lot less light?

No, with such a moderate jump in shutter speeds, there won't be a big decline in power from the HSS mode kicking in.

In a related question, if I am set on ¼ power and the shutter speed keeps getting faster, does the flash compensate, or does my flash light output level start to go down?

The latter. I have made a suggestion to Cactus to automatically compensate for changes in shutter speed when HSS is in use a while ago. Perhaps they can pull it off, perhaps not. We'll have to see.

I always set the EV step the same value on my camera and my V6II. So if the shutter speed is above the sync-speed and I change the shutter speed by two clicks, for example, I know that I need two clicks on the trigger as well.

Could the Yongnuo transmitter be put on top of the V6ii on camera and trigger a YN-560 iii flash on full power?

Yes. You could use PowerSync (aka HyperSync) that way.
If your YN-560 III supports manually engaging HSS then you could even use HSS as the V6II transmitter will generate a sync signal on the hot-shoe.

[Class A]

I was trying to solve my problem with Godox X1T not being available for Pentax by sneaking a Cactus unit in-between my Nikon XT1n transmitter and a bunch of Nikon and manual Godox flashes.

It doesn't work yet (and I feel it should)

I also would have thought this works. A number of people have used the V6II as an "HSS enabler" by stacking another trigger on top of it. For instance, fwbigd used the Godox XT-16 and Pablo Villegas used the Godox X1. There are quite a number of reports about successfully using other triggers on the Cactus community forum.

My guess would be that the camera system should be manually configured to "Pentax", the flash system to "Nikon", and the flash profile to "Auto". TTL pass-through should not be engaged.

[luchoh]

I also would have thought this works. A number of people have used the V6II as an "HSS enabler" by stacking another trigger on top of it. For instance, fwbigd used the Godox XT-16 and Pablo Villegas used the Godox X1. There are quite a number of reports about successfully using other triggers on the Cactus community forum.

My guess would be that the camera system should be manually configured to "Pentax", the flash system to "Nikon", and the flash profile to "Auto". TTL pass-through should not be engaged.

I have X1Tn and XT32c. I bought into both systems hoping I'd be able to find a workaround while Godox and Cactus iron out their bugs.
I have 5 of the new Godox flashes (1 Nikon system and 4 manual).
I am a software engineer and looking at the systems as black boxes I can:
1. Clearly see inconsistencies in interoperability, including with time and device combinations (i.e. the sequence of events things are hooked up and set up can give different results). This is more pronounced with the X1T than with the XT32.
2. Cactus v6ii is clearly affected by the device that sits on top. I could never make K-1 fire above sync speed (both HSS and Power Sync modes) while the latter is possible with XT32 in manual mode.

To me, I'm left with the following choices:
1. Waits for the firmware updates. It is clear to me though (from the Cactus representative replies) that stacking transmitters is not, let's say, encouraged. Future firmware can improve or deteriorate functionality.
2. Get FT16 - in the sister thread this was shown to be working.
3. Get a second v6ii. Hook it up to the Godox Nikon system flash, which conveniently has a master mode.this way I will fire the second v6ii which I turn will fire the rest of the flashes. I am not sure however if I can fire the rest of the groups with the master flash.

I feel option 2 is the best, though I may try 645D ... who knows, maybe the camera also affects interoperability of the transmitters.

And to conclude with the words of Arthur C. Clarke:
Any sufficiently advanced technology is indistinguishable from magic.

---------- Post added 10-05-16 at 11:18 PM ----------

Next thing on my list is covering the non-center pins of the interface between the transmitters. I read on the Cactus forum they had this bug but supposedly they "fixed-ed" it Or maybe it was the Godox forum... long story short, setting the center pin operation was ignored with the previous firmware if more contacts were sensed.

[Class A]

Have you tried "Manual Flash" as the flash system setting on the V6II?

I'd just accept that the trigger stacking does not work, if it weren't for a number of people who say it does work.

Is Pablo Villegas using the X1 for Canon and that makes all the difference?

Perhaps you should flick him a PM?

[Pablo Villegas]

Hi, I use a Pentax 645D, a Cactus V6ii on top, with a X1C on top of the Cactus V6ii, and I can do HSS with a Godox AD360ii C.

Settings are, Cactus V6ii on Tx, camera Pentax, flash Canon, HSS normal. X1C on manual power. Godox AD360ii C Wireless slave manual power.

[UncleVanya]

Easy. Set your exposure for ambient and use flash for fill. Two examples. The first just as I wrote and second with ND filters and a couple of YN 560III's on a piece of mending plate atop a a tripod.

The main idea is, you're making two exposures, one for ambient and one for flash. Once you get the idea of balancing them, you got it. Both of these were with a 50-135 at 2.8 and ISO 80 or 200

I was wondering when nd filters would come up.

[jake14mw]

Thank you very much to everyone for your feedback. I’m going to resummarize my situation, what I have learned, and my conclusion.

I currently shoot outdoor portraits in AV mode. The reason for this is that aperture is critical to what I want my portraits to look like. In many cases, I like to use off camera flash for fill via Yongnuo radio triggers. If the shutter speed needs to be faster than 1/180th, I try to use a reflector to add light to the subject instead of using flash. ISO is set by me to be as low as possible, unless the shutter speed gets too low. This way, flash exposure stays the same until I manually change something.

I did briefly try experimenting with HSS off camera triggering with a Pentax AF360 on camera, triggering an AF540. This seemed to work some of the time, but I was having problems with it, so I abandoned it. Maybe I should have worked harder trying to work through the issues. One thing I did not like was the camera deciding the flash output level, and the level being inconsistent.

When I heard that the Cactus V6 ii triggers allowed you to do HSS and that it was not PTTL, but let you choose power levels manually, I thought that was perfect. I thought this would allow me to shoot the way I do now, but allowed be to trigger a flash when my SS moved to faster than 1/180th.

But… mcgregni burst my bubble and reminded me that in the Pentax world, HSS does not work in AV mode, just M, TV, or TAV. I thought, well… I could try to get used to TAV. It would be kind of like Manual, but at least give me some room where I would still get a proper exposure with some changes in ambient light. My thought was that I would just have to limit the ISO range to a high of 560 or 800. Checked the trusty K-5iis. Hmm, can’t figure out how to limit it. Google search… no way to set ISO range for TAV!!! Strike two. Next thought, Manual Mode with Auto ISO. Uhhhhh….NO. No Auto ISO allowed in Manual. Strike three. I’m out. Someone please correct me if my research has led me astray with any “facts” I have stated in this paragragh.

So, thanks to everyones wonderful feedback in this thread, my conclusion is that I am much less excited about these triggers now, and I have the following four options:
1. Continue to work the way I am now.
2. Continue to work the way I am now, but add ND filters to my arsenal.
3. Work harder in seeing if I can get normal off camera HSS to work for me
4. Buy these triggers knowing that I need to work in Manual exposure mode to make use of HSS with them.

Thanks for your continued help, and of course I hope everyone is learning from what we are discussing.

[UncleVanya]

Manual with autoISO is in fact TAv mode essentially that's why it's not an option.
Other than this you are waaaaay over my head but I am watching to see the options. Item 2 is the way I would have gone to begin with just because it is barely in my wheelhouse but I haven't done it and don't know that challenges it may pose.

[mcgregni]

Jake, its great to see you absorbing such an information overload .... I too think its been a great thread with loads of good contributions, and helpful for us all ..... there will be many many more just reading than actively participating as well.

If you decide to continue with radio manual HSS flash, then your option 4 above is the way to go ..... I have found off camera P-TTL HSS with Pentax flashes to be very good and reliable even in bright sun, so long as you work with the system and stay within the limits of the optical triggering ..... this means setting the slave flash with its sensor pointed at the camera, and pointing the head of the control flash at the slaves sensor, using flash zoom to help direct the angle of beam. Automatic flash has a good advantage over manual for HSS working because it eliminates the extra power adjustment steps needed to compensate for both shutter adjustments and distance changes.

If you exceed the limits that the optical system can cope with then we now have the prospect of the Cacus radio triggers, and all the benefits that radio remote control brings. However ..... as said before, it is not going to be an automated process. My own view is that this is not a concern in situations where you have plenty of time to set up, test eveything, and the ambient lighting is fairly regular plus the situation is not too dynamic with things moving around all the time. When you have changable light plus a dynamic situation and need to move the flashes or the subjects are moving, then IMO automatic HSS flash saves significant effort and reduces complexity.

Remember that M camera mode does provide precise and direct control over aperture .... plus it does over ISO and shutter as well, and precise control over ALL of these things is exactly what you need for HSS flash control. Tav, whilst technically able to enagage a time value shorter than Max Sync, is not a logical or intuitive mode to use for HSS flash IMO ..... the last thing you need with HSS flash is a floating ISO. There can be no logical purpose to a floating ISO for HSS flash as I see it . In fact, there is little point to any ISO setting other than 100 I think, that could be argued. Higher ISO steps simply require a compensating shutter adjustment and the resulting extra power loss which negates the gain from the ISO increase, plus you just lose IQ as the ISO increases.

Have a good think about it .... we are going to be getting more user reports about the V6II triggers, and how people are using them. If you can make the mental jump into manual mode working, both camera and flash, then go for it! I'd think about an RF60 if you need another flash, as it can be paired up with a single V6II, no need for the receiving V6II. Good luck with your deliberations

[clackers]

4.Buy these triggers knowing that I need to work in Manual exposure mode to make use of HSS with them.
.

Just work Manual, mate.

Take charge, you know what style photo you want, don't let a camera second-guess you. You bought a DSLR to get away from a phone's limitations.

[luismpg]

The mode on supported flashes working with Cactus V6/V6II should be set to P-TTL. This is a technical requirement only .... The triggers are manual power control . See the current thread started by me on this forum about HSS and exposure modes with the Cactus V6II .....

---------- Post added 04-10-16 at 20:25 ----------

I would recommend the Cactus RF60 flash with its HSS sympathy mode to be paired with a V6II ... This combination is a very neat manual HSS solution, with no receiving trigger needed, plus full remote power and flash head zoom control.

When I bought my flash a year ago you tell me exactly this by pm . Buy a cactus rf-60 . I didn't follow your advice,, and bought a metz af 52 af
I like it too.

Unfortunately now I've a problem. I'm looking for a cactus trigger but seems I can't have hss.

Maybe it's a question of wait for a new firmware release on cactus v6ii.

Nice work and discussion
Regards

[mcgregni]

Well, I'm lucky to have both Pentax automatic flashes and Cactus manual available, and choose the mode and approach that best suits each situation. What's 'neat' about the V6II plus RF60 flashes is no need for any receiving V6IIs .... and they are a bit pricy so it would add up if you needed multiple HSS slaves with a receiving unit on each. Certainly if someone is looking to get an extra manual flash for HSS work then the RF60 makes great sense. But of course, if you already have dedicated system flashes that can do HSS, then it may be worth the expense of extra V6IIs in order to allow using the flashes you already have.

Lets hope that ClassA and Cactus see this .... as the Cactus experts they should be able to shed light on the situtaion regarding the Metz Af-52 ..... (I thought we had seen here somewhere recently that the flash was OK with the V6II ..... ?)

[jake14mw]

Just work Manual, mate.

... You bought a DSLR to get away from a phone's limitations.

No, I didn't. I started using a DSLR before I started taking pictures with phones.

[clackers]

No, I didn't. I started using a DSLR before I started taking pictures with phones.

Great, it should be easier for you than others!

[luismpg]

Well, I'm lucky to have both Pentax automatic flashes and Cactus manual available, and choose the mode and approach that best suits each situation. What's 'neat' about the V6II plus RF60 flashes is no need for any receiving V6IIs .... and they are a bit pricy so it would add up if you needed multiple HSS slaves with a receiving unit on each. Certainly if someone is looking to get an extra manual flash for HSS work then the RF60 makes great sense. But of course, if you already have dedicated system flashes that can do HSS, then it may be worth the expense of extra V6IIs in order to allow using the flashes you already have.

Lets hope that ClassA and Cactus see this .... as the Cactus experts they should be able to shed light on the situtaion regarding the Metz Af-52 ..... (I thought we had seen here somewhere recently that the flash was OK with the V6II ..... ?)

Thanks mcgreni I've find the post.
https://www.pentaxforums.com/forums/125-flashes-lighting-studio/328467-cactus...speedlite.html

Seems it works. Great Thank you all.