Leonard, You are 100% correct in the example you gave with the two flashes and the ND filter, and that was also what the initial question was about.
My remark starting with 'Actually' only referred to your last paragraph starting with 'Feel free' about how the RTF and the AF500FTZ work. In that specific case a ND filter wouldn't have any impact provided the flash is powerful enough. I hope I didn't cause too much confusion. You don't need Mafud's book. Frits W�thrich Paris, Leonard wrote: > I don't doubt it a minute. My lame little example used two > identical flash > units and a neutral density filter along with a camera that had a > basic TTL > flash capability that triggers both flashes at the same time and then > quenches both of them at the same time, when enough light has reached the > film. It was meant to illustrate a very simple point. I'm sure > that there > are no end of more complex systems that could have been delved > into at great > length but that was my little example and I'm sticking to it. :) This > principle, though admittedly simplified, has a certain amount of > applicability even to the PZ-1p, the RTF, and the AF500FTZ. The original > question seemd to ask about ND filter use on one of the flash > units. I could > have misunderstood, I guess. > > Len > --- > > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, November 20, 2001 9:14 AM > To: [EMAIL PROTECTED] > Subject: Re: TTL multiflash with METZ > > > Actually the PZ-1(p) will use the RTF to reach 1/3 of the light required, > and then switch to the external flash for the remaining 2/3. So that is > different then useing two external flashes and use a ND filter to control > the output between those two. > > Frits W�thrich > > > Let me take a shot at this one and see how it sits with all of > > you. > > > > Let's say we had a camera with two identical flashes on > > brackets. One on the left of the body, and one on tthe right of > > the body. Let's also say both are controlled by the body's TTL > > flash system, > > > > If neither flash had a ND filter, then the exposure made would > > be a perfect balance of light from both flashes, everything else > > being equal. That is, when enough light reached the film the > > flashes would be quenched. > > > > If one of the flash units had an ND filter on it, the TTL system > > would still quench both flashes when enough light has reached > > the film but the flash with no ND filter would contribute more > > light than the flash with an ND filter, giving you one brighter > > source of light on one side of the picture and a dimmer source > > of light acting as fill, to reduce contrast from the other side. > > > > Feel free to correct the error of my thinking but I believe that > > this is how it happens with my PZ-1p when I use the RTF and the > > AF500FTZ together. > > > > Len - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
