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11-19-2016, 11:10 AM   #31
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QuoteOriginally posted by Class A Quote
I think mcgregni is right when he says that this is just a matter of the displayed focal length. The 58 AF-2 does an automatic conversion to APS-C equivalent focal lengths per default.
I do think Cactus has a bug of some description regarding Metz flashes on Pentax. If I put my old Metz 54 on my 645Z it properly sets the zoom level, even factoring in the proper relationship between 645 on a crop sensor and the 35mm equivalent (it has no option to change the scaling factor on this model). Move the flash onto a V6 II and I get a focal length scaling factor applied that is incorrect.

It may be that Cactus isn't reading something from the Pentax bodies to tell it which scaling factor to apply, because it's definitely sending zoom information. If I put my 28-45 on my 645Z and rotate the zoom barrel the flash will track, but just at the wrong zoom figure.

11-19-2016, 04:47 PM   #32
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QuoteOriginally posted by paulster Quote
If I put my 28-45 on my 645Z and rotate the zoom barrel the flash will track, but just at the wrong zoom figure.
Is it just the display of the zoom figures that is wrong, or is the angle of view of illumination achieved by the flash incorrect?
11-20-2016, 03:30 PM   #33
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QuoteOriginally posted by Class A Quote
Is it just the display of the zoom figures that is wrong, or is the angle of view of illumination achieved by the flash incorrect?
Realized that I was wrong in saying the flash zoom will track the lens zoom when off camera, but it is still not working correctly when controlled from the V6 II Tx.

If I set 16mm zoom on the V6 II Tx I get 24mm on the flash (actual zoom position and display value)
If I set 20mm zoom on the V6 II Tx I get 28mm on the flash (actual zoom position and display value)

On a 645Z the ratio should go the other way. The flash should be set wider than the 645 focal length to account for the scale factor between the camera and the flash with its 35mm-based zoom levels. If I have the flash directly on camera with the 55mm lens the flash will zoom to 35mm, which is the closest zoom level it has. This is how it ought to work, but it's working back-to-front on the V6 II.
11-20-2016, 08:50 PM   #34
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QuoteOriginally posted by paulster Quote
Realized that I was wrong in saying the flash zoom will track the lens zoom when off camera, but it is still not working correctly when controlled from the V6 II Tx.
Yes, off-camera flashes don't track the camera's zoom level. I had assumed you were talking about an on-camera TTL pass-through situation.

For off-camera flashes, I'd say it is good they don't follow the camera automatically and that they should just set the zoom setting one specifies with the V6II transmitter. There should be no format conversion whatsoever.

With the "Zoom Size" setting on my 58 AF-2, I can achieve this "no conversion" scenario. Does your flash perhaps have a similar setting? The 58 AF-2 only shows the "Zoom Size" option after the V6II has recognised the flash (or the flash is on a camera, of course).

11-21-2016, 04:53 AM   #35
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Automatic Format Detection is a 'nice to have', but is probably limited to dedicated, proprietary TTL flash systems where the manufacturer has a range of camera system types that share the same flash models ....(eg Pentax with the '35mm', 'Digital', '645' & '67' formats). I shouldn't imagine that a Canon flash will have Format indications for a medium format size sensor .....


Neither does the Cactus RF60, which uses the 35mm (ie 'Full Frame') figures.... from 24mm through to 105mm I think. So if I use the cactus flash on my aps-c K7 then it still displays the same zoom settings and I'd have to mentally calculate the appropriate setting for my focal length in order to ensure a full coverage of the frame (assuming that is what is needed, which its often not).


The difference with a Pentax flash is that it will automatically detect the format, when using an autofocus lens, and save that setting until the flash is put onto a different format camera. Its perhaps important to point out that none of this is at all concerned with the actual physical zoom settings on the flash and the actual angle of light they emit and the area they illuminate. That all stays the same, and the only thing that changes with different camera format settings is the displayed focal length figures (referred to here earlier as the 'conversions').


In all honesty .... when does this actually matter in practice? Certainly not when off-camera ..... then there is no connection between the focal length of the lens and the angle of illumination that is needed. That becomes a creative choice and needs to be assessed visually. The same can be said for on-camera bounced flash, when we actualy have a range of different effects available from different zoom settings, again not directly related to the focal length of the lens.


It perhaps does matter more when using on-camera direct flash, which we might say should be avoided as too harsh and hard .... but outdoors when balancing daylight and flash on subjects with very differing ambient light around them, and this applies to HSS situations as well, then direct on-camera flash is very effective, quick and practical, and will get you an image that just couldn't exist without the flash. In those cases then it is very helpful to see the lens focal length replicated with the flash zoom setting. With that information then we know that our flash coverage will fill the frame if needed, or we can use it to zoom the flash in further to a subject, say if using a 35mm lens for a portrait we might zoom in to the 58mm flash setting to target the subject and not waste unneeded flash light going around the outside.


I can see that in those situations, especially when zooming and shooting in a dynamic way, that having the wrong format indications will make it harder work. But for off-camera work, and in the situation being discussed earlier here with the Cactus V6II, I think its best to just have an idea of the number of zoom positions available, and disregard the actual figures displayed. So just turn the V6II dial all the way left and keep going until the flash stops zooming, and use a step by step approach to 'feel' your way throught the zoom settings.

Last edited by mcgregni; 11-21-2016 at 05:14 AM.
01-03-2017, 09:18 PM   #36
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Cactus tx and off camera flash

A question. If you have a Cactus V6II on the K3/k3II or K1 FF, do you need the off camera flashs' (AF 540 FGZII and AF 360 FGZII) mounted on the Cactus V6II?
or do they "talk" directly to the flash/s. I take it you don't need a flash on the Cactus on the camera to operate? Looking at buying, just need to know how many.

Thanks in advance.
Eric.
01-04-2017, 12:25 AM   #37
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QuoteOriginally posted by Eebll Quote
If you have a Cactus V6II on the K3/k3II or K1 FF, do you need the off camera flashs' (AF 540 FGZII and AF 360 FGZII) mounted on the Cactus V6II?
or do they "talk" directly to the flash/s.
You need one V6II in Tx (transmitter) mode on the camera. It can accommodate an on-camera flash (offering TTL pass-through for it), but it is not necessary to mount one and personally I find the overall package of camera, V6II, and flash a bit much to handle comfortably.

You need as many V6II units in Rx (receiver mode) as you have off-camera flashes. Only the Cactus RF60(x) flash does not require an attached V6II receiver, as it has a radio transceiver built-in already.

So it looks like you'd need three V6II units in total.

01-04-2017, 06:12 AM - 1 Like   #38
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QuoteOriginally posted by Class A Quote
You need one V6II in Tx (transmitter) mode on the camera. It can accommodate an on-camera flash (offering TTL pass-through for it), but it is not necessary to mount one and personally I find the overall package of camera, V6II, and flash a bit much to handle comfortably.

You need as many V6II units in Rx (receiver mode) as you have off-camera flashes. Only the Cactus RF60(x) flash does not require an attached V6II receiver, as it has a radio transceiver built-in already.

So it looks like you'd need three V6II units in total.
Thanks for that, Class A. I thought as much, but one could hope.
07-04-2017, 03:10 AM - 1 Like   #39
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Hello

I've tested this combo, updated to the recent Firmware versions:

Pentax K3II - Firmware V 1.10 ( Realease on 04 August 2016)
Metz 52 AF-1 - Firmware V 1.4 (Realease on 20.04.2017) - Pentax mount
Cactus V6II - Firmware V1.1.010 (Released on 19 May 2017)

Hence there is no particular profile in Cactus V6II for Metz 52 AF-1, I used the Metz 50 AF-1 Profile, and the results are very decent.
Attention: Auto-detect Metz flashes (Auto-Pentax on V6II), will not give good results

So I've tested the following sets:
On Tx: Camera System PENTAX | Flash System PENTAX | Costom Setings OFF | Flash Profile Metz AF50-AF-1
On Rx: Flash System PENTAX | Flash Profile Metz AF50-AF-1

With TTL-pass ON and OFF
Zoom on Metz - Doesn't work even with Zoom Auto set on Metz, The zoom is controlled mannualy on Tx, this is a feature not used for Off Camera Flash.
Focus Lamp (on the V6 II) - It works
good exposure - It works Perfect
max distance on display (changes when you move the apperture or speed dials) - Doesn't work, only changes if set changed on Tx, this is a feature not used for Off Camera Flash.
All works above Max sync speed - It works Perfect, TTL, on HSS, manual, everything works
Rx has a sports mode, that works too.

If used in Manual Mode (Tx - TTL Pass OFF) that gives you more creativity and control, it works really good.

I think this is a really good approach, and for me I'm satisfyied.

I'll keep waiting for next firmare, to have a complete profile,

Special thanks to Class A, dfp771 and mcgregni

Regards.
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