Originally posted by Amoon
Hi. I currently own a TT350P, it works very good but I've been in situations where I need more flash power. So recently I read in the Godox official website, that the latest firmware for TT685C will make it "compatible with Godox wireless Pentax X system".
Does it mean that the upgrade will turn a TT685-C into a more powerful TT350P? With P-TTL and HSS available when attached to the hot shoe of my K-3II?
No. A firmware upgrade cannot physically change the foot of a flash. The pin layout and internal wiring/communication of a TT685-C flash foot remain dedicated to Canon. It can only be TTL/HSS on a Canon camera hotshoe.
But. What does get changed by the firmware upgrade is how the built-in transceiver unit can communicate. Once you do the firmware upgrade, then TT685-C can then be a PTTL/Pentax HSS off-camera radio slave to, say, a TT350-P or XPro-P.
I have a TT685-C that I use with my Canon 5Dii and XPro-C, both on- and off-camera. I had to firmware update it to use it off-camera in TTL/HSS with an XPro-O on my Panasonic GX7, and an XPro-F on my Fuji X100T. But it does work for all three systems. The TT685-C, on the lower left corner of the LCD display will show "Canon", "FUJI" or "OLPS" to indicate which transmitter it last communicated with.
At this time, your only choices for on-camera TTL/HSS are the V1-P, the still-on-preorder V860 III-P, and the TT350-P. I pointedly asked the Godox guys on the
TT685 II announcement on reddit (which conspicuously fails to mention a Pentax version) if there would be a Pentax version and was replied to with a "Will share your feedback with the team!" [muffled scream]. The
TT685 II Sony and Nikon versions are already shipping from B&H for $130, Adorama is shipping the Canon/Nikon/Sony
Flashpoint versions.
The TT685 II, btw, is not an AA-powered V860 III. They've made it cheaper by removing the additional physical features of the LED lamp and TCM physical switch (uses a soft button for that). Still has the slidelock and backwards head tilt. Still has the new button UI/control wheel/menu features of the V1 and V860 III, though, so it's pretty close.
Just me, but until the V860 III-P is actually released, I wouldn't even start hoping for a TT685 II-P, since they're probably going to have to base the design on that. And I would guess that the V860 III-P is probably taking longer because a) sales are lower and b) there are no V860 II-P/TT685-P designs to leverage.
---------- Post added 12-15-21 at 01:08 PM ----------
Originally posted by stevebrot
It means that if you own a TT685C the upgrade will enable it to provide Pentax protocol partial emulation similar to Godox product with native Pentax dedication...
...but only as a radio slave. Godox matches OEM pin placement on the foot of their flashes; it's not a Westcott FJ80/Cactus V6II scenario where the foot is physically designed to be capable of communicating with multiple brands of hotshoe. The physical contact/pin layout on the foot is different between Pentax and Canon and none of the Canon pins can hit the Pentax contacts:
Since only the sync pin will make contact, a TT685-C becomes a manual-only flash on a Pentax hotshoe.
It might have serious miscommunication on an Olympus or Fuji hotshoe where the placement is the same, but the electronic communication is completely different. I once completely fubared all my Godox gear by putting an XPro-C on my Fuji X100T. Took me two hours to reset everything and get it working again. Worked fine as a manual trigger once I taped off the non-sync contacts on the Fuji hotshoe. And it's why I routinely curse Godox for not having a single-pin mode on any of their transmitters aside from the X1T. (Why, Godox, why?!)
---------- Post added 12-15-21 at 01:19 PM ----------
Originally posted by stevebrot
Forum member @Inkista may have additional fine points to offer, but my experience with my Godox/Flashpoint gear has been as follows...
It will "tell" the camera that a P-TTL or HSS flash is attached, but the actual TTL and HSS are the Godox versions. They work the same as far as the camera is concerned....
Yeah, my experience is a little different. For on-camera usage, the TTL/HSS signalling may be more direct than going through a Godox interpretation. I suspect it may just be matching signals based on mapping out what OEM gear sends out on the pins/contacts. What you describe is how the built-in radio transceiver communication works. I have noticed that some models (-O, -F, -S) may behave perfectly fine on-camera while having wonkiness with off-camera use, where translation to Godox's style of communication is imperfect. HSS banding is one common culprit, and there's the infamous Sony underexposure with wider-than-f/4 apertures would be another. These
only happen with off-camera radio use, not on-camera use.
Fuji HSS with manual-only Godox gear is where the wheels come off the wagon for me.

Apparently Fuji's implementation of HSS is whack. They only added HSS as a feature to their cameras in 2016. The newer Godox TTL-capable gear was updated to deal with it, but the older manual Godox gear, like the TT600, V850 II, and XTR16 and XTR16s receivers have massive problems achieving HSS with anything other than an X1T-F transmitter at v03 or later firmware with C.Fn-11 set to 1 or 2. Srsly. I kid you not. My Xpro-F and my TT600 speedlights? HSS no bueno. OTOH, I am shooting with a leaf-shutter X100T, so maybe that's a factor (but it works fine with my TT685-C), but AFAICR, the older pre-radio Godox studio strobe Fuji shooters switching from FTR16 (433 MHz) to XTR16 (2.4 GHz) receivers had the exact same problem with HSS. Why they fixed it on the X1T-F and didn't implement that same fix on the XPro-F or X2T-F is again one of my "why, Godox, why?" laments.