V6 II not triggering early enough on Pentax 645Z

I've just upgraded to 1.1.009 from 1.1.006 and have noticed what appears to be an issue with the timing of the flash signal.  On the 645Z the very bottom of the frame is slightly darker, which suggests that the flash may have fired just after the second curtain started its travel.

I've verified this with an off-camera speedlight (Shanny SN600FGZ) and a studio strobe connected to the Rx via a sync cable, all whilst keeping the shutter speed to X-sync (1/125).  Using a V6 receiver instead of a V6 II seems to help just a tiny amount (still using the V6 II as a Tx), and also taking a sync cable out of the V6 II Tx to the studio strobe also helps a bit, but neither solution is perfect and still leaves a slight darkening at the bottom of the frame.

If I put the Shanny on the camera and remove the triggers from the equation then the illumination is even across the frame.

So it looks like the V6 II Tx isn't getting the 'fire' signal out quite quickly enough on this camera.

I also tried the TYPE1 option, which didn't appear to make any difference at all.

Comments

  • Is this an issue that was introduced with V1.1.009 or did it exist with V1.1.006 already?
  • I had noticed it before, but I was running a funky combination of Tx on 1.1.008 and Rx on 1.1.006 (since downgrading the Rx was enough to get the system communicating at all), so I wasn't using it for any critical work whilst I was waiting for the 1.1.009 update to come out, and wasn't losing sleep over it as a consequence.

    So, in answer to your question, I haven't tried it with a solely 1.1.006 environment.  I just applied the update last night to both units, took some test shots of a plain wall and came away disappointed.
  • Yeah, too bad it isn't working straight away. :(

    With older firmwares, I haven't seen any black bars with my K100D, K-5II, and K-1. Don't have a 645Z. ;)

    I'm pretty sure you shouldn't be seeing any black bars and that
    a) a complete V1.1.006 setup may fix things for you, and
    b) Cactus will most likely keep tweaking V1.1.009 until all Pentax issues have been addressed.


  • Thanks for reporting.

    We don't have the 645Z, need to borrow it from our friend's studio again to verify, probably some time next week. Hope that's alright!

    Cheers!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Not a problem.  I can work around it for the moment by going down to 1/90, which is fine indoors.  Not going to be a whole lot of use to me outside though when I'm battling ambient with a 150mm lens, and the 1/125 X-sync speed is already too slow!
  • Antonio

    I'm hearing rumours of a Pentax beta firmware.  Does this include any 645Z fixes?  I'm really wanting to be able to use my pack outside and I have to be able to at least get up to X-sync speed, if not above.  The 1/125 X-sync speed is already lousy without having to go below that at the moment.
  • See comparison of how evenly the frame is lit from top to bottom at 1/90, versus how bad it is at X-sync.

    (Ignore the left to right; I only set this up quickly with a single head so it's not massively even across the width of the frame.)

    This is with firmware 1.1.006 on both Tx and Rx.  It's as bad with 1.1.009.
  • Hey @paulster,

    I need a hand from you in trying to tune the sync timings on your 645Z.

    Who else has a 645Z here on the forum?

    In the meantime I will send you a PM.

    Cheers!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Antonio

    Happy to help.  At 1/90 with the Broncolor gear it's producing fantastic results.  If we can just get this working at 1/125 as well then I think we'll also be set for HSS since the banding is no worse when you exceed the shutter speed all the way up to 1/4000.  At that point I'll be able to really take advantage of this pack outside.

    Paul
  • Thank you, Paul.

    I will post back updates as we need 645Z users with Canon /Nikon speedlights to calibrate the sync timing.
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • I am using a 645z and a profoto b1 works great in HSS. I am using a Canon version profoto triger,but now I am trying to use a Canon version flashpoint tiger R2 which is a godox rebranded with a flashpoint eVOLV 200 and getting banding over 1/125.

    I would think because the triggers are canon version it should work. The only thing that I can think of it the strobes have different sync technology. The Profoto uses one long pulse v's several pulses on the eVOLV 200.
  • I am using a 645z and a profoto b1 works great in HSS. I am using a Canon version profoto triger,but now I am trying to use a Canon version flashpoint tiger R2 which is a godox rebranded with a flashpoint eVOLV 200 and getting banding over 1/125.

    I would think because the triggers are canon version it should work. The only thing that I can think of it the strobes have different sync technology. The Profoto uses one long pulse v's several pulses on the eVOLV 200.
    Interesting. That could be it too.

    Since you are using the 645Z, would you mind helping us calibrate the sync settings for the 645Z? I'll send you a PM.

    Thanks!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Still no improvement on 1.1.010 using a studio strobe connected via a sync cable (see image attached).

    At X-sync speed (1/125s) I have banding.  Below X-sync speed (1/90s) I don't have banding.  And I can't realistically use 1/90s outside with any reasonable size lens on. The standard X-sync speed of 1/125s is already slow enough as it is.

    The issue I raised isn't about HSS timing, which is what the release notes for 1.1.010 claim to have fixed.  It's about shutter timing at the camera's actual X-sync speed, which clearly isn't right.
  • Thanks for the testing, I am checking with R&D right now. Will report back,

    Cheers!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • I've done some more testing on this with 1.1.010 and there is good and bad news:
    Good news:
    The Shanny SN600FGZ is evenly lit at X-sync (1/125) and 1/90.
    My Broncolor Grafit studio packs are evenly lit at X-sync (1/125) and 1/90.
    Bad news:
    My Broncolor Mobil pack is still giving uneven illumination at X-sync and even illumination at 1/90.

    So it looks like the triggers are right on the cusp of acceptability for triggering, and this is being highlighted by the Broncolor Mobil pack, whereas the much shorter durations of the bigger studio packs make it a non-issue.

    It's a shame that it's the Mobil that exhibits the problem, because that's the pack I want to use outside to overpower the sun and need the shortest shutter speed possible.
  • Thanks @paulster for the update. 

    So it seems like the Bron Mobil pack that is the weakest link? That it does not have native HSS, and it has short flash duration, which is usually a good thing, but when paired with the V6 II for HSS, the duration is not long enough to cover the entire frame.

    BTW I wonder what's so special about 1/90s? Is that the ceiling before loosing even illumination?

    Have you tried higher speeds? What happens?

    Thanks!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Antonio

    The Mobil back actually has a long flash duration, as it isn't an IGBT-controlled flash.  The band you see at the bottom of the image at 1/125 doesn't get any worse all the way up to 1/4000, so the flash duration is certainly long enough for HSS.  The problem is that the flash isn't getting told to fire until too late, so this in combination with its own latency in triggering the strobe means it's not actually occurring until after the second curtain has already started to move.

    The fact that the size of the band seems to be consistent at any shutter speed from 1/125 makes me wonder if this isn't inadvertently getting synced to the second curtain rather than the first curtain on the 645Z.

    I have my shutter speed set in half-stop increments, so 1/90 is my next slowest shutter speed below 1/125.  As you surmise, this is the fastest shutter speed I can use on this particular pack without seeing the banding.
  • Antonio

    Now that you have a 645Z back in the shop, are you able to see if you can do anything to improve the latency on triggering so I might have a chance of using my Mobil pack for HSS?
  • @paulster, let me check and get back to you.
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Still no dice, having upgraded to 1.1.012 and set TYPE 1 as the custom option.  Have the engineers been able to get to the bottom of why we're getting banding on this particular type of pack at the camera's x-sync speed?
  • @paulster, still no dice, meaning it's not working?

    Firmware release notes say banding issue is fixed on the 645Z.

    If you are experiencing banding with your Broncolor Mobil Pack then that's normal, because it appears this flash is "slow", and this cannot be helped. The future Pentax X-TTL firmware may have a chance, but we cannot comment right now.

    Thank you.
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Antonio

    Sorry, I shouldn't have used slang.  Unfortunately it's still not working unless I drop below x-sync.

    If the engineers haven't found any further optimizations they can do for the 645Z in the multi-system firmware then I guess I'm going to have to hope that the Pentax X-TTL one helps things.  It's annoying because the banding doesn't get any worse from 1/125 up to 1/4000, which suggests it would work well in HSS if only the latency wasn't an issue.
  • Thanks for clarifying.

    A real bugger to have a slight shadow near the bottom of the image. Perhaps trade it in with one of your studio strobe that's not having this banding issue.

    FYI Pentax firmware shall be available in a couple months. So you will soon know the answer if X-TTL firmware for Pentax can save the day.

    Cheers!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Fortunately I use my big packs most of the time, and they work just fine, but it's annoying that these battery packs are so close and yet so far.  And I have two of them!

    Keeping my fingers crossed for the X-TTL firmware.
  • Yes, hopefully X-TTL firmware works better with the Mobil packs.
    Good that we have you on our beta testing team! :)
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
  • Hello guys, any update on this?
    Just realized the banding at the bottom of the image at 1/125. I'm using 645z, v6II (.006 )and profoto gear. 
    Everything works fine in other shutter speeds.
  • actually, i think it is a pentax issue. going back to my images i realized that when i used the elinchrom trigger i also got the banding at the bottom at 1/125
  • Hello guys, any update on this?
    Just realized the banding at the bottom of the image at 1/125. I'm using 645z, v6II (.006 )and profoto gear. 
    Everything works fine in other shutter speeds.
    Have you tried 1.1.012 and set Custom Settings to TYPE 1?

    Which Profoto strobe model are you using?
    And Elinchrom?  (we don't have any but could ask if any of our dealers have the same model)

    Thanks!
    Antonio Lao
    Brand Manager
    _____________

    To help us better help you, always state the exact firmware version installed on your Cactus device(s), such as: "1.1.013", "NIK.A.001", "v.103", or "A06".

    TTL or HSS not working on Cactus V6 II and V6 IIs? Be sure to check hot shoe connectivity by doing the <CAMERA INFO> check.

    Feel free to suggest an improvement or share product ideas. Contact us directly at info@cactus-image.com.  At Cactus, we listen. 
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