Guest #12 Posted May 17, 2011 Share #21 Posted May 17, 2011 Advertisement (gone after registration) for entertainment only... ...to get the idea of the relative importance of the different errors. The line with small dashes is the focusing of an actual lens. The dotted line is the error from reframing to rule of thirds. The line with big dashes is the error predicted by the accuracy formula. The solid line is for reference. In the first example with a good lens the focusing error is nothing like the accuracy formula would predict; it's almost nothing. And the reframing error, if you reframe, will dominate. In the second example with a not so good lens, the focusing error dominates the other errors. I think in real life things work out so you can "just about but not quite" do whatever you want. The example is pretty contrived, but it's the same as my experience from shooting day-in, day-out...you will bump up against a couple of other things besides just the physics. Welcome, dear visitor! As registered member you'd see an image here… Simply register for free here – We are always happy to welcome new members! Link to post Share on other sites Simply register for free here – We are always happy to welcome new members! ' data-webShareUrl='https://www.l-camera-forum.com/topic/151516-rangefinder-accuracy/?do=findComment&comment=1674342'>More sharing options...
Advertisement Posted May 17, 2011 Posted May 17, 2011 Hi Guest #12, Take a look here rangefinder accuracy. I'm sure you'll find what you were looking for!
Guest #12 Posted May 18, 2011 Share #22 Posted May 18, 2011 here, someone has posted the same graph before and got the same formula--three guesses. http://www.l-camera-forum.com/leica-forum/digital-forum/7446-rangefinder-accuracy-charts.html Link to post Share on other sites More sharing options...
ho_co Posted May 18, 2011 Author Share #23 Posted May 18, 2011 Gee, I must have an obsession with rangefinder accuracy, you s'pose? I had completely forgotten that exercise. Thanks! Link to post Share on other sites More sharing options...
k-hawinkler Posted May 18, 2011 Share #24 Posted May 18, 2011 Howard, Please keep it up. It's all good. Really cool thread. Thanks, K-H. Link to post Share on other sites More sharing options...
Guest #12 Posted May 20, 2011 Share #25 Posted May 20, 2011 As a post-script, I checked E.P.'s article more carefully and found he is just using the formula above; no magic "equations that are used by Leica... ." I did not bother to check every column...but checked all four tables. The chart, however, is a good trick--I wonder who first drew it. It turns out the accuracy formula is good out to about 20m or so, compared to an exact expression. You cannot draw the chart from the exact expression, however, because then the distance will not cancel out. Link to post Share on other sites More sharing options...
Guest #12 Posted May 21, 2011 Share #26 Posted May 21, 2011 ...gandolfi did a little of this in an older thread... sorry, meant Lindolfi Link to post Share on other sites More sharing options...
ho_co Posted May 27, 2011 Author Share #27 Posted May 27, 2011 Advertisement (gone after registration) Erwin Puts has an article in his book on this subject, as well as in his site.... Maurice, I assume you were referring to the earlier book by Mr Puts. He also presents very much the same graph in his article on pp 246-247 of the new Leica Compendium, which I just received today, along with the relevant formulas. Since he doesn't mention the M8 or M9 in the text of that section, I assume it is taken from his earlier work. However, the graph has been updated to show the rangefinder accuracy of the M8. All in all, an excellent exposition of what's up with the rangefinder! Link to post Share on other sites More sharing options...
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