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Forum: Flashes, Lighting, and Studio
06-03-2018, 05:02 AM
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Sorry to hear.
If there are intermittent contact issues then you'll have a very frustrating time with the V6II.
I had a unit during beta testing that made very unreliable contact on my cameras. The resulting experience was soul destroying. No replicability whatsoever, misfires, incorrect exposures, etc. Just horrible. If you know how to make the cable connect to the K-1 reliably and the V6II connects reliably to the other end of the cable, perhaps that would be a way to establish a reliable connection, at least for testing purposes.
It would be good if you could check whether you can replicate the issues you have experienced on the KP.
I don't know whether Cactus tested the V6II with a KP but in principle it should work.
No worries.
Sorry if my contributions sometimes veer off a bit into technical matters. I blame mcgregni who simply shouldn't trigger me! :D ;) :)
BTW, note that mcgregni made a very good point about your Metz flash being unable to participate in scenarios where the shutter speed exceeds 1/200s and it is optically triggered.
The "banding" you observed might be just the Metz contributing to the exposure erratically? I suggest that for further banding tests, you only use the RF60X. Once you have found a reliable mode of operation, you can add in the Metz. You may have to take certain measures to make the Metz work well, but that is definitely not something you should attempt from the get go.
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Forum: Flashes, Lighting, and Studio
06-03-2018, 04:48 AM
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A P-TTL flash does, however, show distance information (when the flash head is angled forward).
You'll notice that the distance information changes when one adjusts the ISO setting or other camera parameters.
So there is communication between the camera and a P-TTL flash and I'm afraid neither of us have the insider knowledge to state what the information is used for in the flash.
Are you perhaps making assumptions without stating that they are assumptions?
With a flash in "auto zoom" mode, the camera knows exactly what zoom setting the flash has and I don't see how you can exclude that in such cases the camera makes use of that information. AFAIC, the camera would be negligent to not use the information. I don't know whether P-TTL makes use of the information but it would make sense if it did.
Well, camera parameters are definitely needed in some of the modes the V6II can operate in. I don't know to what extent (if any) they are needed during "normal P-TTL working" but I don't think we should assume anything.
Yes, I agree that a detailed discussion is out of place here. I only responded to your view that the parameters displayed on the "camera info" screen are immaterial. That is definitely not the case in general and as usual I'm unable to let such inaccurate statements slide. :)
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Forum: Flashes, Lighting, and Studio
06-02-2018, 10:23 PM
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I have very little experience using the V6II in any other camera mode than "M". During beta testing, I did some experiments in "Av" mode and other modes and the V6II behaved fine, but I did not try to explore all possible behaviour due to the fact that the expected behaviour is not well-documented and that if the V6II works in principle, all observed issues should just reflect the idiosyncrasies of P-TTL.
It is possible, however, that the V6II isn't playing as nicely as it should when modes other than "M" are used. Determining whether that's the case would require comparisons between the behaviours of a P-TTL flash that is directly connected to the camera versus one which uses the V6II for communication.
These banding issues could be due to the V6II firmware needing correction (with respect to modes other than "M") or could perhaps be symptoms of an inconsistent camera/V6II connection.
If banding comes and goes without you touching the V6II at all, I think that should practically rule out an inconsistent camera/V6II connection.
Note that non-banding related issues, e.g., just flat out overexposure, could be just due to normal P-TTL behaviour. You'd have to try and see how a P-TTL flash directly connected to the camera (mounted on the hot-shoe or using a P-TTL cable) behaves in comparison. Your use of an "A"-lens is not helping you at all in those matters. Even with more advanced lenses, I find P-TTL to work amazingly well in some situations but become unpredictable in others.
I would encourage you to use "M" mode, not in order to accommodate the V6II but to get more control, more consistency and fewer surprises in general.
Even P-TTL advocates like mcgregni typically suggest to use "M" mode. Otherwise, there could be a lot of variables to be aware of. If the camera automatically changes the shutter speed, for instance, this will have implications on flashes that are have a manually set power level but fire HSS bursts because the shutter speed is above the camera's sync-speed. Automatically changing ISO values are a known hazard when using P-TTL flashes on- or off-camera.
It seems that you are not using a V6II receiver for the Metz 44 AF-2 but trying to trigger the latter through optical triggering. Is that correct?
If so, I think you'd need to configure the Metz 44 AF-2 in a way that it responds to non-P-TTL flashes. Metz typically dubs this as the "servo" mode (as opposed to "slave" mode). The RF60X will not send out all the palaver that is optically communicated between P-TTL flashes. That's probably why the Metz 44 AF-2 is not responding to the RF60X. Of course, you need a direct line of sight between the Metz's optical sensor and the RF60X but I guess you took care of that.
Again, I have practically no experience using the V6II in combination with "Av" mode.
The "1/200" speed suspiciously matches the sync-speed of the K-1. It appears the camera switches between assuming there is an HSS-capable flash available (or, alternatively, no flash mounted at all) to assuming there a flash mounted that does not support HSS (in which case it wouldn't support shutter speeds higher than 1/200s).
If I were you, I'd make sure that the V6II's sync-mode is set to "HSS NORMAL". I'd also verify that these shutter speed switches occur without me touching the V6II to rule out an intermittent connection issue. I'd also try to check whether any such phenomena occur with the Metz 44 AF-2 mounted to the camera as well. Finally, I'd approach the forum-resident P-TTL expert mcgregni about whether what I'm seeing could be caused by P-TTL matters or require troubleshooting the V6II. :)
Of course, you can just make the jump to become an "M" mode user and then be agnostic about issues that may only be problematic in other modes. If you are mixing ambient (natural light) and flash exposures, you ideally want control over both types of exposures independently. If you are using automated modes, such as "Av", you are leaving quite a bit of control to the camera. Some people like to work with the camera's control and use manual compensation to nudge the camera's choices towards the settings they need. Other people feel that using automated modes in flash photography is analogous to two drivers attempting to be in the driver's seat at the same time. "M" mode may seem intimidating but I find it a lot simpler, as I do not have to second guess as to what the camera is trying to achieve and how all the automated controls of exposure parameters interact with each other. Talk about the camera going to "1/90s" when its trying to drag the shutter in "Av" mode and other such mysteries. :)
There are certainly usages for automated modes in certain fast-paced situations but in my view one then has to familiarise oneself with exactly what the rules of the game are and will have to also ensure that one does not leave the window in which a particular automated mode works well. There are a number of ways to make P-TTL behave badly and one needs to be aware of them in order to avoid them.
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Forum: Flashes, Lighting, and Studio
06-02-2018, 09:30 PM
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Surely the camera ISO setting matters, but why are you implicitly denying the relevance of the data the V6II (or an on-camera flash) receives from the camera?
Some of that data is at least sometimes used to influence flash power levels so there are situations in which the ISO setting displayed on the V6II (whether it is real or corrupted) matters as well.
The practical values are - receiving confirmation that the connection between camera and V6II is still working.
- understanding when exposures do not meet expectations in certain situations.
A normal V6II unit should retain a proper connection throughout a shoot and I'm unfamiliar with situations where an incorrect ISO value may cause incorrect flash exposures. Therefore, I personally also just turn the camera info display off. Other shooters who make use of P-TTL and/or advanced V6II features like "flash compensate" may suffer when the V6II's camera parameter values are not in sync with the actual camera parameter values for whatever reason.
There are probably many reasons for your positive experience (e.g., having a consistent connection between V6II and camera, not using an "A"-lens, ...) but I don't think one can use it to generalise that the exposure parameters known to the V6II are irrelevant.
I think that's probably its main practical purpose.
However, note that it is also useful in understanding the flash power levels calculated by the camera. For instance, the "24mm" zoom setting information tells us that the camera's P-TTL system is treating the 85mm "A"-lens as a 24mm lens for the purposes of its P-TTL calculations. This could have ramifications on choosing the strength of the pre-flash, what parts of the scene are taken into consideration for metering, etc. I don't have any insights into how P-TTL works internally but I think it is plausible that some incorrect data may have a negative impact.
I wonder why P-TTL flash exposures are problematic with "A"-lenses.
The subject distance information from other lenses is so crude, it doesn't really provide the camera with that much more information. If the camera just assumed a moderate distance between camera/flash and subject then most P-TTL exposures should be fine with "A"-lenses, no?
BTW, I do not think it is a question at all whether the zoom setting suggested by the camera is incorrect when using an "A"-lens. My Metz 58 AF-2 reports the same "24mm" and you may want to try one of your Pentax flashes, if you have an "A"-lens available.
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Forum: Flashes, Lighting, and Studio
06-02-2018, 09:46 AM
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I'm not sure that you have the correct idea about these zoom setting indicators.
You need to distinguish between the focal length of the lens, the zoom setting of an on-camera flash, and the zoom setting for off-camera flashes. An on-camera flash's zoom setting will typically mimic (approximate as closely as possible) the focal length of the lens (and follow it in the case of adjustments to a zoom lens). Off-camera flashes, however, may have zoom settings (expressed in "mm", like a focal length) that are completely independent of the lens' focal length.
So, in essence:
What the V6II displays with a "mm" unit on the "camera info" screen, is a flash zoom setting that it receives from the camera (and that an on-camera flash would follow, if configured to "auto-zoom").
What the V6II displays with "mm" units four times on the normal status screen are the zoom settings of the off-camera flashes in groups A, B, C, and D.
It is normal for the on-camera flash zoom setting to be different to the individual (manually controlled) zoom settings for the off-camera flashes in groups A-D.
For some reason, apparently the camera is still sending information to the V6II which the latter tries to process.
I'd follow mcgregni's advice and simply turn off the "CAMERA INFO" display. This should address your current issue of a "camera info" screen making it temporarily impossible to see the normal status screen.
That's probably because you allow the camera to automatically adjust its ISO setting (in addition to the shutter speed setting). The V6II's ISO display should mirror what the camera indicates.
I'm assuming that you may have an easier time, if you switched to manual ("M") mode, but turning off the "CAMERA INFO" screen should also help and then you can see how far you can get with "Av" mode.
Such differences should normally not occur. I wouldn't worry though, as long as you are getting correct exposures.
The camera info display shows "24mm" because the camera fails to correctly report the manually set focal length. If you were using an FA lens, for instance, the camera would report the correct zoom setting to the V6II (and an on-camera flash).
I verified this by mounting my Metz 58 AF-2 flash to my camera. When I mount one of my FA Ltds, the displayed zoom setting ("AZoom" value) is appropriate (i.e., not identical to the focal length, but as close as possible).
If I mount my Rokinon (Samyang) 85/1.4, the zoom setting on the Metz 58 AF-2 shows "24mm", so the flash and V6II are in agreement. Apparently Pentax believe there is no point in properly supporting mere "A"-lenses, given that the latter don't provide any distance information.
The actual value shown may have some impact on how P-TTL calculates exposures -- mcgregni might know something about that -- but hopefully you can ignore all that for your purposes. The "camera info" display is really most useful to detect camera-V6II connection issues. If the values on the V6II's "camera info" display stop responding to changes on the camera then you should re-seat the V6II. However, outside this exception, you should be able to ignore the "camera info" values reported.
That's not quite true.
The camera settings reported by the camera are used by the V6II to support advanced automatic flash power compensation modes. For instance, it is possible to configure the V6II so that any changes to the camera settings automatically cause the flash power to be adjusted, even when the flash is manually controlled. This makes it easy to manually dial in the power and then change a setting on the camera (e.g. the aperture) without having to manually adjust the manual flash power setting on the V6II.
It seems safe to say that Bruce should not worry about any of this for the time being, but it is not correct to say that the displayed values are always inconsequential for actual shooting.
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