Archived posting to the Leica Users Group, 2006/12/28
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Doug.. The way the sensor works is to open up ALL the (electronic) gates of the array at the same time, and to keep those gates open until the "close" signal is given. During that period, the light is collected or integrated into a charge that is then measured as the light hitting the array. The important issue is that all the array cells are opened at the same time and closed at the same time. This is not a sequential act that would allow a slit shutter to operate if the slit would cover the sensor area in a time slower than the gates are open. I have agreed that in the case of the multiple flash mode on the R8/9 or M8, a slit shutter is used as you state... the integration time is opened up to a longer period, then the slit shutter is set to 1/8000 of a second and the flash fires multiple times so that the entire sensor area is covered evenly with the flashed light as the slit moves. In the case that Leica has made the gated function of the sensor NOT the main timing ingredient, and uses the regular and slit shutter to time the exposure, I have already made the argument that the shutter would need to be of very high quality, timed, accurate, etc. The R8 shutter is most likely like this. But when electronic gating is available, and there is no need for mechanical shutter accuracy ( as required in a film/digital hybrid like the R8/9 with the DMR) it would be a waste of money and a accuracy down play to have the mechanical slit control the timing when it is inherently available in the digital domain for less than pennies with increased accuracy. Could it be done? Sure. Would any rational engineer or manufacturing guy do it without some really good reason that he would have to defend to the top levels of management? Not and keep his job . Therefore my conclusion.... it is done digitally and the slit shutter is relegated to the special flash situation. Am I right? Obviously, I think so. But unless I had access to the design team at Solms, and further understood why they might do something that is pretty expensive and not required for more than 1 mode ( and a pretty obscure one at that) , I'll stand my ground. I have heard no argument that convinces me otherwise. OTOH, if I am wrong, ( which I have said is possible since I am deducing this from available application information and not inside hard data information about the M8 from the design team) and the digital sensor timing of the M8 is not used to time exposures, but the mechanical shutter is used, this is very bad for Leica. Their solution is way too expensive from a manufacturing point of view; they have a not-required redundant system of precision mechanics and electronics; customers will have cameras going out of mechanical timing calibration; and you have a very scary scenario for Leica in general: Pissed off customers. Let's hope I am right. Frank Filippone red735i@earthlink.net