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Frequently Asked Questions

 

Questions about Flash & Camera

  1. Do I need a high-speed camera to take high-speed photos?

  2. Can I use my point-and-shoot camera?

  3. What can I use for a flash unit?

  4. How can I get a Vivitar 283 flash unit? How about a 285?

  5. My flash doesn't have a PC cord.  How do I connect it to a trigger?

  6. Where can I get flash accessories?

  7. How do I shorten the duration of the flash?

  8. What do I do if I need a flash duration of a microsecond or less?

  9. What are the pinouts for the light sensor socket on the Vivitar 283?

  10. How can I connect a variable resistor in place of the light sensor socket on the Vivitar 285?

1. Do I need a high-speed camera to take high-speed photos?

 

Not at all.  The brief exposure time needed to capture "frozen" images of high-speed subjects is provided by the flash unit in high-speed flash photography.  (If you're interested in high-speed motion picture photography that's another matter and does require a special camera.)  The camera, in fact, is usually used on the bulb setting.  That is, the shutter is held wide open in a darkened room in readiness for the flash discharge.  It's the brief discharge (as short as 1/30,000 second with common flash units) that "stops" the action. 

 

For more discussion of the use of electronic flash for stopping action, go here. To see an action-stopping photograph taken with a pinhole camera, go here.

 

2. Can I use my point-and-shoot camera?

 

Point-and-shoot cameras are typically too automatic for serious high-speed work.  One has to be able to adjust these three things on the camera:  aperture, focus, and shutter speed (to bulb setting).  Point-and-shoot cameras are designed for convenience and usually eliminate the need for decisions about exposure and focusing.  There are ways, however, to trick an automatic camera into taking decent high-speed photos. See more information here.

 

3.  What can I use for a flash unit?

 

Nowadays, most if not all flash units that you buy at photo stores have automatic exposure control.  That's the main requirement if you want to use a flash unit for high-speed photography.  It also helps to have high light output.  (The higher the guide number, the better.)  Most flash units in the $75 and higher range are going to do the job. 

 

Other features to look for:  1)  It helps if the unit has a PC cord.  Otherwise, you'll have to buy a special adapter for the flash foot.  That's another $10-$15. 2)  If the unit has variable-power adjustment, that will make it easy to control the flash duration.

 

For details on the above, go here.

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4.  How can I get a Vivitar 283 flash unit? How about a 285HV?

 

These are excellent flash units for high-speed photography.  Their use is described in detail in the Guidebook. Unfortunately, this classic unit isn't being manufactured anymore.  However, they were made for so many years and were a staple for reporters that it's easy to find them used in camera stores and on Ebay.

 

If you prefer a new unit, try the 283's cousin, the Vivitar 285HV. The 285HV is similar to the 283.  Both have a removable photo sensor on the front of the unit.  The 285HV has a feature that allows for variable power settings.  This makes it easy to decrease flash duration just by decreasing the power setting.  For the shortest duration, one should select the lowest power setting.  (There is an accessory available for the 283 that provides variable power settings.  See Appendix B of the Guidebook.)

 

By the way, the Vivitar D283 isn't the same as the 283 described above.

 

5.  My flash doesn't have a PC cord.  How do I connect it to a trigger?

 

Not a problem. Adapter shoes are available that have a PC cord.  A photo and description are given here.

 

If you need a PC cord specifically for a Vivitar 283, search for Vivitar PC-1 on the website of your favorite photographic supplier. Some suppliers are listed in the answer to the next question.

 

6.  Where can I get flash accessories?

 

Try your local camera store or mail order from places like Adorama, B&H Photo & Video, Midwest Photo Exchange, and Porter’s Camera Store.  We've usually been able to find what we need at these places, but there should be others for the looking.  For information on useful accessories, go here and here.

 

7. How do I shorten the duration of the flash?

 

This requires that your flash have automatic exposure control and/or variable-power control.  These are discussed in detail in the Flash section.

 

8. What do I do if I need a flash duration of a microsecond or less?

 

High-voltage sparks are used to obtain these short durations.  Such spark sources are used in research and industry and cost much more than flash units available from photo stores.  The least inexpensive off-the-shelf unit that we're aware of is the Spot from Prism Science Works.  The Spot produces light from a spark of half a microsecond duration.

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9. What are the pinouts for the light sensor socket on the Vivitar 283?

 

See the article, Using the Vivitar 283s Light Sensor Socket.

 

10. How can I connect a variable resistor in place of the light sensor socket on the Vivitar 285? 

 

The diagram of the 285 pinouts is shown to the right. Use pins 2 and 3 to connect a fixed or variable resistor in order to control flash duration. Be very careful to get the right pins. Pin 1 is high voltage. You could burn out your flash unit and get a bad shock if you connected the wrong pins. For more information on pinouts, see this page. Note that there is a discrepancy on that page between the text and the photo. The text shows to connect pins 4&5 for remote operation, but the photo shows that pin 4 is unused. A helpful DIYer reports that pins 5&6 are the ones that must be connected for remote operation.

 

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