[Lord Lucan]

I often use this page which gives the trigger voltages of hundreds of older flash units. I went to the page today and got a re-direct to a different page, although still on the same Botzilla website. What concerns me is that the new page looks rather bare-boned compared with the old one, for example all the external links are broken, and while all the data is still there it makes me wonder if this page will remain available in the longer term. I found the older version on the WayBackMachine and took a copy just in case.

The page does not seem to have been updated for years, but in a way it does not need to be because all new flash units are bound to have low trigger voltages. There are however lots of gaps in its data on older units. I did send a couple of reports to it myself once but nothing happened.

The Botzilla Strobes Page

[stevebrot]

'Tis true. The detailed lists are gone. The new mantra is to measure the voltage for any flash on which there is doubt and be aware of the limits of shoes in your kit. That said, users here may provide useful information to the community by adding measured trigger voltages to flash descriptions when reviewing or recommending vintage flashes.


Steve

[Dale H. Cook]

I found the older version on the WayBackMachine and took a copy just in case.

Would you please post a link to the Wayback Machine archive of that Botzilla page? I can't seem to find it.

I own a few original (Japanese) production Vivitar 283s which have been modified for 5 volts on the shoe so I can use them off-camera with wireless triggers.

[Lord Lucan]

Would you please post a link to the Wayback Machine archive of that Botzilla page? I can't seem to find it.

Here is the page as it was on 7 May 2021. You can pick other dates from the timeline bar along the top but they are all much the same. I could not find even the new version by starting from the Botzilla home page.
Photo Strobe Trigger Voltages

I own a few original (Japanese) production Vivitar 283s which have been modified for 5 volts on the shoe

That can be done, or some people use an external voltage dropper*. I understand the very similar 285HV (not the plain 285) had a safe voltage. But these days Ebay etc are flooded with film era flash units at give-away prices, including ones with safe voltages, partly because many people believe they cannot be used with digital cameras. The issue is not just about digital; later film era cameras also had a lot of electronics so flash units were already being designed accordingly. That's why the later 283s came with reduced voltages although for some reason Vivitar did not reflect this in the name - they should have called it the Mk ii or something.

So late film era flash units can be used straight on the camera as long as you check with Botzilla's page before you buy, and with a digital voltmeter after you buy, and you don't mind managing without P-TTL (or whatever proprietory TTL system your camera has) - because the old style Auto mode with a sensor on the flash unit is better than digital era P-TTL anyway, except for close-up shots. I would not mix brand dedications though.

I recently got a Sunpak 26DX for 99 pence - safe voltage, built like a brick, multiple Auto and Manual modes, and Pentax film-era dedication including TTL with its plug-in module. It even gives the flash ready signal in my Pentax DSLR. I also got its bigger brother Sunpak 36DX (same power as the Vivitar 283/285 but launched at a later time) for £15.

users here may provide useful information to the community by adding measured trigger voltages to flash descriptions when reviewing or recommending vintage flashes.

I always do. On another website someone made the point that the result can be misleading [because the voltage is on a very small capacitor, and the meter itself can deceptively pull the voltage down]. I would not rely on an old analog (wire coil) voltmeter and even the cheaper digital multimeters can pull the voltage down a bit. However, if the voltmeter shows a high voltage then the unit's voltage is definitely high; and the voltages tend to fall into two clear groups - over 100v or under 12v. For example I measured my Pentax AF280T as 7.5 volts, while Pentax themselves (presumably with more accurate instruments) said 7.8v; I take that as my yardstick and limit for other units.

* Which are a rip-off price; and because they fit between the camera hot shoe and the flash unit foot, they add to the leverage of the unit's weight on the camera. Some hot-shoe units are heavy and there are many reports of the camera hot shoes being half ripped out.

[Not a Number]

The information on that page is way too conflicting to consider it reliable or appear to be based on one report. You're better off testing each flash individually.

On the subject of the Vivitar 285 I've tested 5 Japan made units and they all measure out to around 6 volts. Usually to the sum of the voltages of the batteries being used. I've even posted a video showing me testing one of them.

My Minolta 280PX measures out to the sum of the voltages of the batteries in use, not 1.8V as listed.

[Lord Lucan]

The information on that page is way too conflicting to consider it reliable or appear to be based on one report. You're better off testing each flash individually.

As I said, the page is to be considered before you buy, but you still need to test before you actually use it. The values in the page might be wrong, but they might also be all the information you have. For example if Ebay tempts me with a Metz 45-CT1 (a potato masher favourite of old pros) for my DSLR, but then I check Botzilla and find two reports, one of 218v and one of 600v (!), I don't care that they don't exactly agree, or that maybe someone doesn't know how to read a multimeter - I simply won't buy it. Occam's razor. I am going to buy something else such as the later Metz 45-CL1 which is reported as 7.6v or 6v, but I will still measure it for myself when I receive it.

I've tested 5 Japan made units and they all measure out to around 6 volts. Usually to the sum of the voltages of the batteries being used.

That may be co-incidence, but it depends on the design. I have a Sunpak Auto 36DX which Botzilla reports as 2.4v or 5.86v; it doesn't really matter because both values are low. But this shows a gap in the Botzilla data. The 36DX uses a plug-in module which gives camera brand dedication and I happen to have several modules meant for different brands - and they all have different trigger voltages. A Pentax module gives 4.5v, a Ricoh module gives 12.5v and a Nikon module gives 11.5v. The battery voltage is 6v.

[BSULMON]

It is so easy to use a secure-flash-system between the flash and the camera.
Look at the PDF I had made some times ago (in french)

Attached Images

synchro flash HT - solutions v2.pdf (2.73 MB, 10 views)

[Lord Lucan]

Look at the PDF I had made some times ago (in french)

Interesting project and neatly done. My French is not very good but circuit diagrams use a universal language. So the optical isolation guarantees security. I would be nervous about using a Wein type safesync device between the camera hot shoe and a heavy shoe-mounted flash unit such as the Vivitar 283, because of the extra leverage the weight of the unit would have on the camera shoe, but in your case the safesync device is carrying only the relatively light controllers of your hammerhead units.

[Dale H. Cook]

So the optical isolation guarantees security.

That is how I modify the Vivitar 283s for off-camera use with wireless triggers. I feed the 6VDC battery voltage through the LED input of an SCR opto-isolator and then to the center pin of the shoe. The SCR output of the opto can't handle the ~300VDC flash trigger voltage, so I use the opto output to gate a higher voltage SCR to pull the trigger voltage to ground. Everything is inside the flash body so the exterior is physically the same.