Archived posting to the Leica Users Group, 2005/05/17
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Douglas, Sounds like a better case than mine. With my astigmatism all picture frames are slightly larger on one side and one of two glasses of wine with equal volumes always appears slightly larger. I claim that this astigmatism accounts for my sloping horizons, the verticals are usually OK. Perhaps it will be better when I get "bionic" lens for my flaring mark I models. Lee At 12:46 AM 5/18/2005 +0200, you wrote: >Much better Peter, >I know I'm a nit-picker, shifts, be they ever so small, just hit me >right in the optic nerve. > >It's a matter of "Seismogram Eyeball", I spent over 30 years having to >recognise amplitude and phase differences of seismic signals and logs, or >time shifts of around 1 millisecond on seismic profiles (at a standard >display scale that's about 0.1mm differences or smaller).Not finding the >signal could mean the difference between drilling on a dry prospect or >finding a gas reservoir. >"Sharps Eyes" had quite a reputation in the world of exploration geophysics. > >It has a nasty side effect - I turned into a habitual picture frame >straightener,BTW my wife is an architect and has the same gift/problem. > >I put a narrow grid over the picture to check how much I was out on my >first estimate, and I came to 0.4 - 0.85 degrees left correction. 0.85 at >the left hand edge (the parapet and windows of the rectangular building), >0.5 over the ends of the handrails at each side of the shot, based on >putting the spire of St Pauls as a vertical axis dead centre. 0.4 - 0.5 >also fits the columns of the dome. This could infer a tiny bit of lens >distortion, that the camera was not quite in the horizontal plane, >possibly tilted up a bit, or that the scanned negative was not quite flat. >cheers >Douglas > >Peter Dzwig wrote: > >>Douglas Sharp wrote: >> >>>An excellent shot Peter, >>>love the symmetry! >>>but couldn't it take a slight correction of the horizontal? >>>I think its about 1 or 1.5 degrees out of kilter. Otherwise perfect for >>>me. >>>cheers >>>Douglas >>Douglas and List, >>see which one you you think is straight... >>http://gallery.leica-users.org/album164/MilleniumBridge200505 >>the original >>or: >>http://gallery.leica-users.org/album164/MilleniumBridge200505Rot1 >>I think that it is it straightened...it took 0.4 degrees of rotation. If >>that does truly fix it (I am not entirely sure) Douglas you have very >>sharp eyes!! >>All the best, >>Peter >> >>_______________________________________________ >>Leica Users Group. >>See http://leica-users.org/mailman/listinfo/lug for more information >_______________________________________________ >Leica Users Group. >See http://leica-users.org/mailman/listinfo/lug for more information