Archived posting to the Leica Users Group, 2014/04/08
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Adam my dear on screen friend! :-) Thank you so very much for putting it into a language I can understand! :-) Actually the best teaching & me learning! :-) I've ever had on this coding aspect explained to me. Thank you most sincerely for your understanding of the old lad and my un-educated state. However! Now I'm more understanding of a technical aspect I never understood before! Bless you! The rant button has been silenced! Well until? ;-) ;-) Oh heck you know these days and an "OLD FILM USER FOR OVER A HALF CENTURY?" There's bound to be somethng new that'll throw me into a snit state! :-) Although I'll try harder to sort of bite my tongue / typing fingers and save the LUG from another of my screaming rants once again!" :-) :-) :-) cheers, ted ----- Original Message ----- From: "Adam Bridge" <abridge at mac.com> To: "Leica Users Group" <lug at leica-users.org> Sent: Tuesday, April 08, 2014 3:52 PM Subject: Re: [Leica] Coded or non coded lenses, that is the question ADAM! > Hi Ted, > > With our M8's it's not so much of an issue because the sensor is smaller. > The weird things happen out at the edges where the light comes in at a > steeper angle. > > When you think of a sensor on a digital camera you need to think of the > light-sensitive part living down in a pit. Sort of like you're standing at > the bottom of a well looking up at the sky. Light from the back of the > lens spreads across the sensor. If you're in the middle then you get all > the light. But out the edges the light hits the side of the pit and > doesn't make it to the bottom. > > The answer is to put a small lens (they call them "micro-lenses" at the > top of the pit which gathers the light and directs it down to the bottom. > But the design of that lens would have to be different for each lens you > mount on your camera. What to do? Well, every camera has a small computer > in it to handle taking the electronic information from each little sensor > location and using that in some rather complex ways to organize it into a > "picture" that makes sense. If the computer knows that you've got a 24mm > f2 lens on it can adjust for both how the light from the lens reaches the > sensor at the bottom of each pit AND it can even adjust for known problems > in the design of that particular lens! > > Of course with film this isn't a problem. With black and white film the > layer of light-sensitive particles is very thin while for color the > different layers are still very thin - no pits! > > I hope this helps. I could probably do a neat little illustration if it > would help you. > > It IS very complicated. We're still at that awkward phase of technology > where exactly how to do the engineering is being worked out in an almost > minute by minute advance. Film, however, has been a mature technology for > decades. Now, if you had started out in photography in the 19th century > you'd have done much the same except you'd be worried about wet plates, or > dry plates, or film, or different formats. That all settled down with a > few formats and lots of well-understood chemistry to make it all happen. > Just think about the different developers used on something like Tri-X and > all the discussions on this list about which was best and how to get the > optimum result. > > That's happening all over again but its even more complex now. But, I > think, it'll start to get simpler again. When my grandson (now 6 months > old) is our age.... > > Happy snaps! As always I read all of your posts and am deeply grateful for > them, even when you're feeling cantankerous. <grin> > > Adam > > On 2014 Apr 7, at 6:56 PM, tedgrant at shaw.ca wrote: > >> I shoot with my M8 and whatever lens it maybe, my images look just super >> fine while printing 13X19 size prints. So is there some kind of >> situation? Lighting effect? Whatever? A situation where I can shoot a >> scene and see a diffeence. I'll rent a coded lens or maybe someone living >> near by has one I'll ask a loan for a few hours or so. And shoot with >> both non-coded and coded. >> >> Maybe that'll make me see the errors of my anti-coding rants! >> thank you. >> cheers, >> ted > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information