Archived posting to the Leica Users Group, 2001/09/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Dans un courrier daté du 24/09/01 21:07:27 Paris, Madrid (heure d'été), tdschofield@msn.com a écrit : > There once was a line of thought that horizontal shutters gave a more > pleasing perspective for horizontally moving subjects than vetical shutters. > > Something called focal plane shutter distortion which occurs when the > subject is moving while the shutter slit is travelling its course. The > subject was not in the same place when the slit started as it is in when the > > slit finishes, elongating or compressing the subject. Remeber, even though > any given point on the film maybe getting only 1/1000 or 1/2000 of a second > of light, one spot may be getting its 1/1000th or 1/2000th of light, 15 or > 30/1000ths of a sec. later than another spot (e.g. with a 1mm slit width). > That, I beleive, is one reason why only the consumer models (e.ge. > Nikkormat) had vertical travelling shutters and the professional models had > horizontal shutters (e.g. F, F2, F3). > > Maybe its no longer an issue with modern, high speed shutters, or just that > no one talks about sacrificing this issue to get other advantages (higher > shutter speeds, higher flash sych, etc.), and the absence of people using MF > > focal plane shutter cameras (Pentax 67, Exacta 66, Pentacon, Hasselblad F) > for action phtography. > > Tom Schofield > > I think horizontal ( H ) shutters were created due to the search for a higher wanted speed . In a H shutter , the blades travel less than in the V one , thus permitting a higher speed . So I think H shutters are just another technology , compared to V , that allow higher speed . But who needs 1/8000 Th , if not just for allowing higher film speed during daytime ? JO GOODTIMES -FRANCE - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html