Archived posting to the Leica Users Group, 2009/02/13
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Henning I meant that I wouldn't expect significant IR from those subjects behind glass. I agree those subjects would not be big IR candidates anyway. I assumed that the window glass would attenuate IR as well. Sounds like I should not have linked the two ideas. I'm no scientist there certainly. For fun I must have a play and educate myself on that now. Regarding the small blue highlights, I have seen secondary mirror images of point light sources in some of my shots. For example this shot with the 75 Summicron and UV/IR. (4 second exposure). You should be able to make out a ghost image of the moon crescent as well as some stars repeated as blue dots. I assumed this was due to reflections back into the camera from the filter. I based that on an article in the Feb 2007 LFI demonstrating this with a night street shot of street lights and headlights. The article states that the ghost images are caused by the presence of the filter. http://gallery.leica-users.org/v/gh/a/ns/Sky.jpg.html In Chris's shot you can certainly see a set of reflections on the window glass. I love to play with reflection shots like this myself which is partly why I was staring into this enjoyable one by Chris. I believe that the two blue spots above the girl to the left, are a ghost of another set of reflections on the window glass! The blue colour is a clue to me. Note the yellow original sets above and to the left that are on the window glass I think. Never mind just some technical opinion from me that I thought might be of interest. As a practical matter those spots are easy to retouch of course. I put another up for discussion on this subect http://gallery.leica-users.org/v/gh/a/usa/f/Cantina.jpg.html This is a 28 uncropped, through a window at close range. Of interest maybe is you can see my left arm and watch over the back of the guy to the left and I think our table edge on the lady's back to the right. Look at the hat of the background guy to the right and the blonde hair of the lady just below her left ear position. You probably need to look at the larger version to see more clearly. Anyway I find these details fascinating to learn about. I'd value any comment from you, or others. Cheers Geoff 'Licence to Chill' 2009/2/13 Henning Wulff <henningw@archiphoto.com> > A nice set, Chris but to clarify what Geoff has written: > > The window glass won't do anything for/against the IR. Your available light > just happens to be low IR content, which is usual in winter. > > The reflection may or may not be due to the UV filter. It looks like the > picture is shot through glass, the most likely cause is the window glass as > that causes way more reflections than filters, an of a somewhat different > type. > > > > > Chris that is a thoughtful and well constructed group. The second ice shot >> is especially appealing. >> There's nothing in any of the content that might provide a reason for the >> UV/IR . >> If you'd like a technical comment on that aspect,look at the >> Selfridges shots. I suspect that the window glass has prevented any >> possible >> mis-rendering of the dark fabrics anyway. But your UV has given you the >> same >> minor artefacts that a UV/IR (or any filter) would have. See the small >> blue >> internal reflections (second shot) of the point light sources? >> >> 2009/2/13 Christopher Birchenhall <crbirchenhall@googlemail.com> >> >> LUGers >>> >>> I took my recently acquired M8 out with a LTM 50mm Summicron f2 >>> collapsible on two occasions. This lens came as part of a very >>> collectible IIIf R/D kit. I am not a collector so I decided to cash in >>> the body and case (sigh). But the lens is for me one of my best. We >>> get on very well. We "clicked" :-) One or two of these pics may >>> appeal but I can't but offer to share my delight at using the new >>> electronic camera with a "peach" of a classic lens (with a standard UV >>> filter and no 6-bit coding). >>> >>> I managed to get into the centre of Manchester (UK) with some good >>> winter sunlight. Some of the subject matter (graffiti/street art?) may >>> not appeal to all but I am ok with this stuff - a couple do involve >>> the "fair" sex? >>> >>> http://gallery.leica-users.org/v/crb/M8/Manchester/ >>> >>> We had a quick walk along my staple venue (Macclesfield Canal) when it >>> was cold and the canal was partly frozen - a barge had clearly passed >>> through and broken up the ice - we had a fine half pint of a winter >>> warmer ale half way through! >>> >>> http://gallery.leica-users.org/v/crb/M8/canal/ >>> >>> Needless to say C&C are welcome. >>> >>> Chris B >>> >>> _______________________________________________ >>> Leica Users Group. >>> See http://leica-users.org/mailman/listinfo/lug for more information >>> >>> >> >> >> -- >> Cheers >> Geoff >> 'Licence to Chill' >> >> _______________________________________________ >> Leica Users Group. >> See http://leica-users.org/mailman/listinfo/lug for more information >> > > -- > > * Henning J. Wulff > /|\ Wulff Photography & Design > /###\ mailto:henningw@archiphoto.com > |[ ]| http://www.archiphoto.com > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > --