Archived posting to the Leica Users Group, 2002/07/09
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Fill flash is hardly a "fast" flash. Is usually is set up such that the flash proportion is pretty close to the ambient light.. maybe a stop or 2 below, but still, pretty close. That means the the ambient light is pretty close to F stop @ 1/50 of a second. Therefore you get movement artifacts at 135mm as the ambient light is making a major inpact on the exposed film.. Try again, using the head on flash, in the dark. Now the ambient light required maybe 5-6-7 F stops more open. The flash is providing the majority of the light to the film. The flash will be putting out light at maybe 1/10,000 of a second. It freezes the action. Yes, you still have SOME residual ambient light hitting the film, but it is proportionally much less than the flash light. It does provide some "movement" of the subject, but it is approximately "averaged" with the flash. At 5 stops away, the movement is providing 1/32 of the total hitting the film. So small that you can not fuind it easily, and therefore the action is stopped, and the picture looks like it was taken with less movement of the subject or a higher shutter speed, especially important with the 135mm focal length.. Going back to the SF20 flash.... If you wish to improve the movement of the 135 lens in the shot, you need a flash that provides MUCH more light output, and give up on fill flash. Then you will be 1) shooting at a smaller F Stop, which helps with DOF 2) decreasing the ambient light component of the action ( this provides a darker background compared to the face which may NOT be what is desired) 3) provide the flash with an even faster flash duration, say 1/100,000 of a second that freezes the action more than 1/1,000 of a second I think I have overkilled this answer, but to add to the overkill more.... My Honeywell 780 potato masher flash puts out so much light, that the high movement of indoor basketball players is totally arrested by the fast flash speed and low ambient light component, when taken at 1/125 of a second at F8 on my old Contax RF camera. But fill flash it is not. It could have been set for bounce flash in the original picture, with some loss of light, but it STILL would have worked, albeit manual flash mode. The issue is the strength of the flash tube. The SF20 is pretty meek. My old potato flasher is really strong. You would need a modern Metz 45 or better, 60 series flash to be totally integrated with the M6 TTL sensor. Does anyone know if the M6TTL will work with the Metz 45 of 60 series potato mashers? Which model numbers, which "adapter" model numbers? Or use a tripod with the original set up. KISS. Frank Filippone red735i@earthlink.net - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html