Archived posting to the Leica Users Group, 2007/01/15
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Len thanks for posting some stuff so promptly. It's very enjoyable to be discussing actual Leica photographs on the LUG! I agree that the effect seems more apparent in your examples, perhaps, than mine. Mine too would have been at moderate apertures. I may have been misleading discussing the wide open performance. I think what we are looking at is a sky polarisation effect rather than true vignetting. It may be exacerbated by conversion to the digital versions that we are all looking at. I notice this with conversion to black and white particularly with significant tonal adjustments. Another factor may be where we have cropped with the different shots. For my images, I crop to A4 proportions. That typically discards the extreme outside edges of the original 24 x36mm frame (where some of the effect resides). Look carefully at the bottom corners of Img145 from your son's examples. <http://gallery.leica-users.org/v/LeonardT/28mm/Img145.jpg.html> I don't see any effect in the bottom corners. It's not apparent in shots where the bottom corners are very dark, of course. That might square with my polarisation theory. When I look carefully, on a light box at my Velvia originals, the effect is much less apparent, as well. Herr Puts describes the 2 28 asph as having marginally higher fall off than the Elmarit and the new 2.8 28 asph sounds very interesting indeed, doesn't it? I think that the current 28 is an absolute triumph of design and a lens that I really enjoy using. Cheers Hoppy -----Original Message----- From: lug-bounces+hoppyman=bigpond.net.au@leica-users.org [mailto:lug-bounces+hoppyman=bigpond.net.au@leica-users.org] On Behalf Of Leonard Taupier Sent: Tuesday, 16 January 2007 12:08 To: Leica Users Group Subject: Re: [Leica] 28mm Summicron vignetting Mark, Not so sure. Leica's data shows a lot of vignetting at f5.6. Len On Jan 15, 2007, at 8:56 PM, Mark Rabiner wrote: > On 1/15/07 7:35 PM, "Leonard Taupier" <len-1@comcast.net> typed: > >> Here are a few examples of vignetting using the 28mm Summicron. These >> were shot in b&w but the sky was crystal clear blue. These were shot >> by my son at Zion, Bryce and the Grand canyon. >> >> <http://gallery.leica-users.org/v/LeonardT/28mm/Img138.jpg.html> >> >> <http://gallery.leica-users.org/v/LeonardT/28mm/Img145.jpg.html> >> >> <http://gallery.leica-users.org/v/LeonardT/28mm/Img225.jpg.html> >> >> <http://gallery.leica-users.org/v/LeonardT/28mm/Img136.jpg.html> >> >> I'm not sure of the f stop but I believe they were in the f5.6 to f8 >> range. We ran a test in my backyard of the Summicron versus the >> Elmarit (not asph). The Elmarit had a little less vignetting. All the >> examples were easily fixed in Photoshop using the lens distortion >> filter. >> >> Len >> >> >> > I don't think you're going to get vignetting at f5.6 to f8 with > even the > cheapest dumbest glass. > I think this is sky polarization or digital stuff emphasized by > extreme > addition of contrast. > > > Mark Rabiner > New York, NY > 40?47'59.79"N > 73?57'32.37"W > > http://rabinergroup.com/ > > > > > _______________________________________________ > 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