A Recent Portrait Shoot

I managed to persuade (well bribe!) the eldest daughter to stay still enough for me to mess around and get a few shots .... for a short while before she found better things to do .

Taken with the K7 and SMC F35-70mm. The lighting is with a Pentax AF-540FGZ in a softbox to the right (P-TTL wireless), a side/rim light from behind left with the Cactus RF60, and an on-camera fill-in with the Pentax AF-540FGZII (bounced into a corner over my left shoulder - P-TTL wireless). The Cactus was controlled remotely from a V6 transmitter on the camera hotshoe with the on-camera flash on top of that ('TTL Pass-through' mode)..... and yes, I had just as much fun setting that all up as I did taking the photos!

Thanks for taking a look ......

How are you finding those Cactuses?

I like the lighting of the first shot the best.

I love the Cactus equipment, and it integrates well with the Pentax flashes as you can use the V6 on the camera with a Pentax flash on top of that in what's called 'TTL Passthrough Mode'.

If you haven't seen it already check out my thread here .... link ....

I know you were interested in HSS work Richard, and I've put it all together in that demo with the P-TTL system as well. But you do still need a P-TTL Dedicated HSS capable flash though. I'm very happy with the approach though as its reliable, better than some of the other 'workarounds' which seem to keep giving people so many headaches.

The advantage of the RF60 is that, just like the Pentax flashes, it emits a true HSS continuous burst of light when set to its 'HSS Sympathy' mode ... many manual alternatives do not do that. This makes the exposures very accurate and reliable. The power and flash head zoom can still be controlled remotely by radio from the V6 even though the actual triggering is optical via the sensor on the RF60.

In this set here I took advantage of the radio aspect by using the RF60 behind the sofa, so 'out-of-sight'. The Pentax flashes performed beautifully alongside it though in fully automatic P-TTL wireless mode.

So you like the Cactus units then?

I took a lot of time to read up and try and digest the jumble of information and questions surrounding the issues. I specifically wanted more power and multi-flash capabilities for HSS but didn't want to have to buy another (3rd) dedicated system flash. Plus I needed some radio remote control for those inaccessible positions where optical communication is unreliable.

I liked the idea of remote power and zoom control from the camera, plus the V6 provides expansion options with its 4 groups for the same channel (so I could, for example, get another V6 to use with one Pentax flash if I needed remote manual control, or another RF60 for a two-flash manual radio system. So there's expansion potential there.

I think they are very good value for the features, and are well made. Not the same build quality as the Pentax flashes as they are built more to a budget, but certainly not cheap and nasty. However I also feel that the Pentax P-TTL dedicated flashes are very good value for what they offer. The two systems can be made to work well side by side, I feel they complement each other.

Of interest is the fact that when combining manual flash exposure from the RF60 with P-TTL from the Pentax units, the two do not interfere with each other at all ... this is because the RF60 does not fire until the main flash trigger signal occurs, and the P-TTL pre-flashes have already finished. So the Manual flash light effect is not seen by the Pentax metering system .... it is something to be manually controlled and added in separately.

like

Good results there Nigel....

Lovely images those Nigel...particularly like the middle one with the teddies. Great technical shots and a very relaxed pose from such a young model.

regards

Karlo

Nice set Nigel. the first is a little hot on the left I think, but the others are very even.
Just to clear up one point; can the Cactus transmit an HSS signal to other HSS compatible flashes like the Metz, or is it only capable of receiving the signal either from the hotshoe or another Cactus?

Thanks! Ah, now is that what would happen if we added a 'Like' button to this site ?

Thanks also Stephen, Karlo & Mark

Mark, regarding the HSS situation with cactus .... firstly obviously, this particular portrait set does not use HSS (there is not ambient lighting in these shots here). If you want to see my demo of multi-flash wireless HSS with the Cactus RF60 then click through to PF here ..... link

The main thing to appreciate with HSS and a manual flash like the RF60 is that it is not possible to directly trigger that flash by radio signal from the transmitter on the camera. This is because above 180thsec the Pentax DSLRs do not send a standard triggering signal that the transmitter can respond to. The only way to generate the firing signal is via a dedicated system flash on the hotshoe that is set for HSS Sync mode. This dedicated flash will send out pre-flashes for both metering and mode / power instructions to any dedicated system slave flashes.

These pre-flashes can only be interpreted by dedicated system flashes set as slaves. The RF60 cannot interpret these signals but it does have both an 'HSS Sympathy' mode (which generates the continuous pulses of 'HSS type' output), plus it has 2 'Optical Slave' modes (which turn it into a 'dumb slave'), which means it will fire when its optical sensor 'sees' another flash firing. So to get it to fire an HSS output it is necessary to activate both HSS Sympathy mode AND one of the two optical slave modes.

OS1 mode fires on the first detected flash, which when working with a Pentax flash in HS mode will be the first pre-flash from the on-camera triggering flash. This necessitates a delay to be set on the RF60 of around 90-115milliseconds (depends on camera model and flash model) in order for the output flash to fire at the correct time after the pre-flashes have finished. The dedicated system flashes manage all this automatically (see, we ARE getting plenty for our money), but the RF60 needs it all to be set up by the user.

The OS 2 mode fires on the second detected flash (normally expected to be the actual exposure flash) but if you are operating your Pentax on-camera trigger flash in 'Wireless Control' mode then there is an additional pre-flash to send mode and power output information to the dedicated slaves, and the RF60 will detect that instead ... so a delay of around 12-18ms is needed in this optical mode.

So ... the Cactus flash is not triggering any other flashes ... that only happens to flashes set to 'dumb optical slave' mode. The dedicated system flashes are not operating in dumb slave mode, but rather P-TTL wireless, and in fact the entire Pentax flash system would be unaware of the RF60s presense .... they function as two completely separate side-by-side systems. The RF60 detects the pre-flash of the on-camera flash, then waits for the set delay until firing, as it is operating as a 'dumb optical slave'.

My use of the V6 is entirely optional. I used it on camera in the HSS shoot as a convenience, because its radio control functions for power and flash head zoom still work with the RF60- even though the RF60 is not getting its trigger signal from the V6.

With a V6 on the camera, you can attach your Pentax dedicated flash on top of the V6 and activate 'TTL-PassThrough' mode on V6 .... the flash now 'thinks' is is directly on the camera and is unaware of the V6's presence.

Very nice shots Nigel, I like the lighting and also how you have kept the background nice and dark. And again the K7 and SMC F35-70mm combo does the business!

Superb shots, love the lighting and the dark background and your little model is stunning.

A delightful set, Nigel. What lovely lighting and a relaxed sitter too. Now I challenge you to see if the set-up can capture a squirming, uncooperative, fast-moving baby...

That's a very helpful response as usual Nigel, thanks.
So if you mount the RF60 on the camera, the camera is unaware of any HSS ability and defaults to sync speed.
As such the rf60 can't become a transmitter for any off-camera flash on HSS.
It's one area where I'm getting really frustrated with Pentax (or lack of support for Pentax). That and tethering.

Nice

The light to the left of the first image I find a little hot and the second could benefit with a hair light behind her but apart from that I think these are fine images