Electronic Flashgun Problem

[Rob]

I have just bought a Vivitar 285 flashgun that is playing up and i'm looking for help!

It's wierd cos it charges up fine, and the lights on the back work just fine. However when fired, either manually or by a slave unit, it just "ticks", no big flash, no recharging of the capacitor, just a little "tick". That's not the wierd part, if i turn it on a fire the gun before it is fully charged up (as in before the ok lights start flash at you), it fires fine!  :-\ Me dont get it!

It's like it may have a voltage protector on it, to stop too much current going into the bulb, and that it's set wrong. But that's all i can think of. Any other ideas?

 

[footleg]

It could be that the auto sensor is faulty, and so cutting out the power before the flash fires properly? The sensor is supposed to detect the light emitted and cut off the flash before all the power is used once a threshold of light output has been detected. See if you can cover the sensor, or set the flash to fully manual if that is an option.

 

[Rob]

Hi, cheers for the responce. However it is not a problem with the auto sensor. It operates the same using all the settings, a sensor off a different gun, and without one in at all.

 

[biffa]

Several of my flashes have started doing that and the solution is to buy a new one on ebay (and maybe even sell the old one)!

 

[DavidGibson]

Hi, cheers for the responce. However it is not a problem with the auto sensor. It operates the same using all the settings, a sensor off a different gun, and without one in at all.

I think you might have misubnderstood Footleg's answer. The "sensor" is a very small light sensor on the front of the flashgun, somewhere. It is not the same thing as the thing you connect to the flashgun. You need to cover the sensor with something opaque, or make sure you have set the gun to a full-manual mode where it does not use its built-in light sensor.

 

[Misty]

I'm not sure this is any help, you sound pretty compitent.

Firstly, is the flash a dedicated unit to the camera in question? I have found that a non dedicated flash unit is better for cave photography due to the shorting out with the slave in the condtions....Not what you would do in normal dry conditions but I was reading something on this so read below. Maybe look at the infra red triggering. Firefly is a popular one for cavers as an example and I don't know what you are using? Also See below:

"Connect the Firefly 2 slave unit to the flash gun (strobe) using the hot shoe adaptor (or PC synch lead or 6.25/0.25" jack).

Attach the Firefly 2 slave unit to the flash gun using the self-adhesive hook & loop fastener provided. Do not fix it adjacent to the flash gun's battery compartment as this can be a source of interference which could cause spurious triggering.
Switch the flash gun on and test using another flash gun or TV remote control at close range. Note that range is reduced in high ambient light levels! The unit should not be used in fluorescent lighting as this will cause it to trigger continuously.

For caving or outdoor use it is strongly recommended that all seams and particularly the cable grommet are protected with waterproof cloth "gaffer" tape or silicone bath sealant before use. However, do not cover the central 25mm of the infra-red window as this is where the sensor is located. In addition, covering the screw holes will prevent the screws from rusting. To protect both Firefly 2 and flash gun, sealing both in a clear plastic bag keeps the worst of the mud and damp away and will prolong the life of the equipment. SAFETY WARNING! Wet flash guns can be extremely dangerous when wet due to the high voltages used.

If you have not yet acquired a flash gun (strobe) for use with the Firefly 2 we recommend the use of a "non dedicated" flash gun. These usually have a single contact on the square section of the plastic moulding that comes into contact with the hot shoe. Conversely "dedicated" units usually have more than one contact (often three). A flash gun of guide number 25-30m (100ft) @ 100ASA would be a good choice.

Infra-Red Triggering
Infra-red triggering is desirable in many circumstances because direct light from a flash gun at the camera would be detrimental to the picture being taken. This is particularly true when using the unit for cave photography as infra-red triggering prevents light from the trigger flash gun being reflected off water vapour from the photographer and spoiling the picture. An infra-red filter for turning any flash gun into an infra-red trigger is now included with the Firefly 2 (after July 2000). It is an unexposed but processed piece of slide film. To construct an infra-red trigger:

Place the infra-red filter provided over the front of the lens of the trigger flash gun (the one connected to the camera) and cut it with scissors so that it is just larger than the transparent area of the lens.
Tape it on with as small an overlap with the lens as possible using cloth or insulation tape. "

Hope this helps
MXX

 

[francis]

Great guide 

Thanks!

Francis

 

[Cave_Troll]

or use Biological Slave Units(tm) to trigger your remote flashes.
The best ones available can be activated by a choice of methods including

* throwing rocks
* pulling bits of string
* voice activation
or the most sensitive
* activation on the sound of the shutter opening
thus avoiding the need to faff around with bits of exposed film.

They also
* carry themselves into the cave
* can be set to operate on different channels if you have more than one
* can be selectively reprogrammed remotely to fire any number of times from 0 to 10
* may even carry your tripod as well if you're lucky.

 

[Rob]

Misty, cheers for the Firefly guide but unfortunately it isn't a problem with the slave unit, just the flash gun.

Hi, cheers for the responce. However it is not a problem with the auto sensor. It operates the same using all the settings, a sensor off a different gun, and without one in at all.

I think you might have misubnderstood Footleg's answer. The "sensor" is a very small light sensor on the front of the flashgun, somewhere. It is not the same thing as the thing you connect to the flashgun. You need to cover the sensor with something opaque, or make sure you have set the gun to a full-manual mode where it does not use its built-in light sensor.

In normal guns yes you are right. However with the vivitar 283/285 range it its detachable, as can be seen in the picture below as the small cylindrical part with "vari power" written on it.

After recently purchasing the service manual for it, i took it apart a few times to check that all the bits and bobs were in the right place. At first i was extremely careful that it was fully discharged before i took it apart...

It's amazing how familiarity breeds contempt