Thanks again.Use this filmmaking technique to create beautifully cinematic footage for less than $500. My thanks to all correspondents, I shall go along with the solution proposed by a1ex until such time as Canon provide a firmware solution. As mentioned in my earlier reponse to Paul B I have been using Wein and Paramount safe-sync devices for some six or seven years but anyone thinking of using old flash units on dslrs would do well to read the advice John has provided. John from PA provides wise warnings on the risks involved in using old flash units with modern dslrs. Both gentlemen have however made a good point about using the internal flash to fire an external unit so thanks to you both for that useful hint. Moppie's comments on the flash shoe contact solution looked interesting but Ramon's note rather negates the hardware modification suggestion. And, no, I don't have the resources of a large organisation to turn to! I am retired and simply an amateur microscopist 'working' on my own.Ī1ex's follow-up on Magic Lantern was also of interest and I favour the "on-and-off" approach he suggests. Thanks to MelCat for introducing me to Magic Lantern I have not yet found a solution there but will make contact and see what may be done. In reply to Tony Long, yes, my 580EX Speedlite works perfectly off camera but, as mentioned, it is not suitable for use with the camera on a microscope, where flash duration is difficult to adjust. I am most grateful for your comments and have found them all helpful.
Thank you to all who have tried to sort out for me the 600D external flash restriction. Better safe than sorry, since that flash when firing can fry that electronic shutter! If you have one of the high-voltage flashes and you wish to contunue using it look into a Wein Safe-Sync shoe (Google it).
#Magic lantern canon t3i 600d tv#
If you don't have a multimeter, take the flash with batteries to a local Radio Shack or TV Repair and do the procedure there. Then measure the voltage between the center pin and the outer contact on the flash hot shoe. Simply turn on the flash and wait for it to charge up (green ready light on). You can determine the voltage of your particular unit with a digital multimeter. Later models, identified as made in China or Korea are down around 15 volts. Unfortunately many of the early flashes had 200 to 250 volts across those terminals and many modern DSLR's, because the "switch" is now electronic, can only handle relatively small voltages, sometimes as little a 6! Very old 283's (commonly made in Japan) were up around 300 volts. A "switch" inside the camera provides closure of a circuit when the shutter fires, causing the flash to fire at the appropriate time. īasically the flash, when charged, has a voltage across its terminals. The reasons are discussed in great detail at m/photo/strobeVolts.html. 1/30,000 the sec flash duration as the sole illuminant.īrian, using an old flash with a modern day DSLR can be very risky (as Perfect 10 pointed out). I will try to attach a couple of jpegs that show one of my microscopes set up with a Canon EOS 60D using Live View and with a Vivitar 283 flash firing through the light path the other shot is a typical subject a rotifer (approx 0.5 mm total length) feeding by whirling the head mounted cilia to draw in microscopical algae etc. To my knowledge the Canon EOS T3i Rebel/ 600D is the first of the company's Live View models that deliberately prevents non-Canon flash units from firing when the camera is in Live View mode - and it is a work-round to this specific omission that I am trying to find. Vivitar 283 flash units are probably unique in that the flash duration is easily adjusted using a wired remote control unit and many microscopists, amateur and professional, swear by the powerful 283 units. Framing and photographing them requires both a rapid hand and eye response and a very brief flash duration. Using the open flash technique would not work for me: I use flash to freeze the high-speed motion of protozoa cilia and other such free-living biological specimens. I use Wein and Paramount 'safe sync' devices to obviate the problem. I should mention that I have been using various Canon dslr cameras with Vivitar 283 flash units for the past six or seven years and am well aware of the trigger voltage hazard the 'old style' flash units pose to our modern electronically packed dslrs. Thanks PaulB, Xarqi and SnapFire for your speedy reponses.
Have you checked the trigger voltages of the 600D and the Vivitar flash first though? If the 600D requires only the trigger voltage that Canon EX guns supply then a higher trigger voltage could fry the flash circuits in the camera. It could be to do with the different trigger voltages of non-Canon flashes.
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