Vivitar DF-383 and V6 II: Flash cut-off in HSS

seaf18

Am getting flash cut-off (top of frame lit with flash, bottom not) with Normal HSS ON; OFF is good up to 1/250. Flash is a Panasonic/Olympus version; is auto-profiled as "O". Camera: Lumix GX8. How do I get the HHS to work? Thanks.

seaf18

Setting flash sync in-camera to 2nd curtain seems to work. Why?

Antonio

@seaf18

From looking at the spec here, the DF-383 does not natively support HSS.
http://www.vivitar.com/product/117/archive/1120/df-383

That is the reason you are seeing the cut-off, aka banding.

When you set 2nd Curtain, it may have limited your camera's shutter speed to below x-sync. Check the image exif and see if it was really shot above 1/250s?

Thank you.

seaf18

Antonio,

I think you're right about the DF-383. It's, apparently, NOT truly a DMW-FL360L alternative. My experience with the V6 IIs hasn't been without difficulty. Behavior has been odd. For example, even though my GX8 camera system registers as Oly m43 and both Vivitar and Panasonic flashes register similarly, the V6 IIs will not trigger. Changing the camera system to Auto fixes this. 

Your info has been helpful in isolating some vexing issues. Thanks.

Antonio

Changing the camera system to Auto fixes this. 

Hello @seaf18

Can you clarify on this?

So you did the half-press shutter when V6 II auto-detects your GX8 as "O" (Olympus / Panasonic)?

Whereas before you manually select the camera system as "O"?

Technically there is not a difference. But perhaps during auto-detect the camera hot shoe pins confirmed alignment.

FYI, you may not have noticed, we recently post an update about compatibility with GX8 in HSS. Due to timing requirements by the GX8 (super quick) off-camera flash signals could not keep up so it will only support up to 1/4000s. At 1/8000s there will be banding issues.

At the moment we listed the GX8 as not HSS compatible but we are considering in changing that to supporting HSS up to 1/4000s.

Thank you.

seaf18

Antonio,

Prior messages were posted before the firmware was updated on my three V6 IIs. Here's the post-update latest: 

Yes, I'm getting "O" sync via auto-detect most of the time (it's random and not associated with hot shoe pin placement). I can also select "O". Best of all, my DMW-FL360L gives me HSS. Didn't test 1/8000, so I'll take your word for the 1/4000 max. Info is good to know. Thanks. And, yes, I saw the 8/26 GX8 compatibility update. I'm pleased to report that I survived the blood pressure spike.

Oddly, when first setting up, the flash(es) will fire via the V6 II test/shutter button, but will NOT fire when the GX8 shutter button is pressed. Workaround I stumbled into was to reset the camera system from "O" to "Others". The flash(es) fire. I then revert to the Olympus camera selection, and everything is fine. 

FWIW, my set-up routine starts with turning on the flash and then the V6 II (to Rx). I then boot the camera, depress the shutter halfway, and turn on the V6 II (to TX). You should know that the results of the routine vary. Occasionally, everything works. Most often, I have to do some toggling to get things up and running.

seaf18

Antonio,

Did some further testing. Looks like banding begins somewhere before 1/1600. 1/800 is clean. 1/1600 has some minor banding top of frame. Not good. Hope this helps.

Antonio

Thanks for the update.
Have you tried removing the metal hot shoe spring plate on the GX8?
We find it helps with the hot shoe connection.

As for 1/1600s, are you using RF60 as off-camera flash?
For the same timing reason + the fact that RF60 is still a manual flash, there are no pre-flash so power pops at the very begining of the frame. We post a note on RF60's page on the same day we did for the V6 II.

Alas - it's a great camera but not sure why Panasonic tuned it so quick. Even their latest GX85 is not like this.

seaf18

Spring plates on all Cactus units have been removed. Flash used for the most recent tests is a Panasonic DMW-FL360L set on TTL FP Auto. 

I agree. The GX8 rocks. Got any pull with Panasonic? Might "tuning" be a firmware fix by Cactus and/or Panasonic? What exactly needs to be done? Am happy to send Panny a request. Got contact info? 

You might consider rallying the Panny/Cactus user troops to send similar requests. I'd even consider opening a Twitter account. Develop the communications strategy, sign me up. What about enlisting photo sites to publish a feature article (DP Preview, others?). Got access to a social media/pr/promotion expert? Yeah, let's get this done.

Antonio

Spring plates on all Cactus units have been removed. Flash used for the most recent tests is a Panasonic 

You should remove the spring plate on your Panasonic camera, not the V6 II.

It's Panasonic's own settings, nothing we can do.

Googled Panasonic Lumix Japan, you can fill out an enquiry form but I doubt they would do anything just for us?
https://crews.iccc.panasonic.co.jp/csform/form.do

seaf18

Oops.  

 V6 IIs have spring plates again. GX8 is plateless. 

Will write Panasonic. But before I do I need to know what, specifically, they need to do to their settings or timing, or whatever. Is there a Cactus engineering contact I can give them?

Thanks.

Antonio

Tell Panasonic that they did not leave enough time buffer between x-sync signal and when the shutter opens. As for contact, just put my name.

All the best contacting Ideas for Life.

seaf18

Contact URL (https://crews.iccc.panasonic.co.jp/csform/form.do) gives me a blank screen. Alternatives?

Regardless, will pursue other Panasonic contact options. 

Do you have a media contact list? It dawned on me that contacting a few notable media influencers, i.e., respected well-knowns who have  written GX8 reviews, would be useful -- if for no other reason than to mine them for marketing/engineering contact info. Who knows, they might even put their weight behind an initiative to fix the timing issue.

Thanks.

Antonio

Contact URL (https://crews.iccc.panasonic.co.jp/csform/form.do) gives me a blank screen. Alternatives?

Try this:
https://crews.iccc.panasonic.co.jp/csform/agree.do?cid=D000100008&aid=0

Then click on the button on the left.

It's all in Japanese, so translate it first with Google then fill out the form. But I don't know if big corp such as Panasonic would respond, or if they do, how quickly. You will need a contact within Panasonic who is in charge of R&D.

Good luck!