I would have expected, that a pro style camera like the *ist D would have a some kind of isolater built in?
Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -----Oprindelig meddelelse----- Fra: Don Sanderson [mailto:[EMAIL PROTECTED] Sendt: 18. december 2004 16:32 Til: PDML Emne: "safe" Flash Sync Voltages All the talk about 'safe' flashes to use on the D got me a little concerned. The last thing I want to do is damage the poor thing. :-( I took some measurements from various units that I use. Here are the sync pin voltages I measured from various flash units: Pentax 200T 4.65 Pentax 280T 7.18 Pentax AF-360FGZ 3.01 Pentax AF-500FTZ 3.55 Vivitar 285HV 5.80 Vivitar 285 6.24 Yake M-110 Studio Flash 8.09 I no longer have an O'Scope so I can't measure any 'spike' voltages present at the sync pin when fired. These spikes are what could do real damage. In a properly designed trigger circuit there should be no spikes but I can't prove their presence or absence on these units. As far as I can see the ist D manual only mentions these flash models: 240,330,360,400,500. The 360 and 500 I measured are the lowest sync pin voltage of the lot. This leads me to believe that the newer Pentax's are designed to operate at lower, (sub-TTL logic) levels. I'm reasonably OK with the 200T but the Yake and the 280T really scare me. There is such a thing as a "flash isolator" available. It fits in the hot shoe and protects the camera from overvoltage/spikes at the sync pin. I will be buying one very soon for the 285s and Yake! I will also not be using the 280T on the D anymore. Don
