Archived posting to the Leica Users Group, 2009/09/15
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hi Dennis, Thanks for your insights, which I appreciate, and which helped me understand more of the system design, manufacture, and quality assurance aspects of the M9 and all digital cameras. My two cents' worth: It was my experience in the aerospace world that the interfaces between sub-systems (as between the sensor assembly, control board, camera frame, etc.) are the result of many competing realities covering the life cycle of the product, only a few of which we imagine that we can identify by a quick look at the final assembly process. I am confident you are familiar with these realities so I won't go into them here but repair and upgrade costs are in the mix somewhere, to be sure. I wish I knew the whole story of how the interfaces for the M9 were chosen, and, like you, I hope they were sub-optimized for future sensor, memory, and processor upgrades; but given what we do not know, including projected time horizons for potential upgrades, my guess is that Leica's M9 sub-system optimization was for M9 performance, quality and reliability right out of the box, with everything else secondary, which seems to be their usual practice. But that's just my guess. The M9 assembly final sequence in the video is to me just a very slight lifting of the negligee that covers Leica's operations. And, as all negligees are intended to do, that little peek makes me wish that I could see more! All the best, Bill On Sep 14, 2009, at 11:40 PM, Dennis wrote: > Hi Geoff, > > The CCD is an analog to digital conversion device and on a die to > die basis there will be variations that while within the > manufacturer's, (Kodak), specifications could be characterized on a > die to die basis. A designer could simply design for the nominal > spec and not worry too much about the effects of variation as a > result of the CCD manufacturing process. However the ultimate would > be to measure the characteristic of each individual die and use > those parameters in the control logic that is processing the digital > output of the die. To do this the parameter of the die have to be > stored somewhere. In watching the video it's stated that the control > board is "paired" with the sensor assembly. That tells me that > characteristic parameters for the sensor is stored on the control > board, not on the sensor assembly, (where I think they should be > stored). I would put them on the sensor assembly because it makes > repair much easier. If the cost of repair is not an issue then fine, > it's usually the customers money anyway. I assume that Jenoptik made > this decision and Leica accepted it but I think Leica should have > pushed back on this one. Maybe it would delay the introduction of > the camera, I don't know. > > The ultimate objective would be to have the algorithms and equations > in the control board driven completely by parameters from the sensor > assembly. If achieved, then you could upgrade a camera by changing > just the sensor assembly. Could it be done? I don't know, but I do > think it should be a design objective. An extreme upgrade could run > into a processing power issue where the speed of the control board > doesn't allow the camera to meet the design objectives, too slow. In > either case, depending on how much firmware is involved, you can > come away with general purpose firmware so that new models don't > entail firmware rewrites, and that can save a lot of time and money. > > Shims are undesirable in any manufacturing process. Good design will > almost always obviate the need for shims. At first I thought the > issue was the frame the sensor is mounted it, it looks like a sheet > metal stamping. But I wondered about the mechanical specifications > on the Kodak sensor. Looking at the KAF-10500 data sheet, I just > picked one available online, the mechanical specifications are > surprisingly loose so it seems to me the shimming is not within > Leica's control. I realize this is probably an issue that all > digital camera manufacturers have. > > I have no doubt about Leica's use of technology to measure I also > have no doubt about Nikon, Canon, etc., ability to measure. Most > likely the difference in use of those measurements is use of > robotics to make adjustments, possibly using screw based adjustment > mechanisms. > > > > > Geoff Hopkinson wrote: >> Dennis the matching of the sensor to its board is performed by >> Jenoptik and >> there is no insight in that video as to Jenoptik's processes at all. >> What is the issue in your opinion with the shimming process?. It is >> a Leica >> response to the criticality of sensor placement to extract the best >> from the >> lens performance. Leica are using very modern precision measurement >> processes that report the shimming adjustments needed and down to one >> hundredth of a mm increments at three points. I would be very >> surprised if >> any other camera company works to that level of accuracy. Can you >> provide >> examples of how it should be done differently? >> You might like to read some of the reporting that has surfaced >> recently >> regarding the digital back sample variations in high end medium >> format >> cameras for comparison. >> >> >> 2009/9/15 Dennis <dennis at hale-pohaku.net> >> >> >>> Ok, Luminous Landscape titled it "M9" but all I saw was M8s. >>> >>> From what I saw Leica needs to look at improving their manufacturing >>> processes. The matching of the sensor to the control board would >>> be a good >>> place to start. No wonder it costs a fortune to replace a control >>> board. >>> The sensor assembly should include all the sensor parameters >>> needed by the >>> control board. I could talk a lot about this but doubt anyone is >>> interested. >>> >>> The shimming of the sensor is another issue. >>> >>> Well, it was about the M8, maybe the M9 has improved processes. >>> Somehow I >>> doubt it. >>> >>> >>> Vick Ko wrote: >>> >>> >>>> See the video about the M9 at Solms? >>>> >>>> http://www.luminous-landscape.com/videos/m9-video.shtml >>>> > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information