Archived posting to the Leica Users Group, 2003/12/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Furthermore although the test is crude to the point that it is allmost absurd it does show that 40 lp/mm is easily attainable from a camera that hangs from a cable.At shutter speeds as low as 1 second. I could not find info on that anywhere else. jes > Of course! :-) > > -----Original Message----- > From: owner-leica-users@mejac.palo-alto.ca.us > [mailto:owner-leica-users@mejac.palo-alto.ca.us] On Behalf Of animal > Sent: Wednesday, December 24, 2003 5:03 PM > To: leica-users@mejac.palo-alto.ca.us > Subject: Re: [Leica] Fw: looking for line pairs with a stabiliser and a > Leica and question > > > we want to take pictures of something from our workplace at night What > else? silly man > > ----- Original Message ----- > From: "B. D. Colen" <bdcolen@earthlink.net> > To: <leica-users@mejac.palo-alto.ca.us> > Sent: Wednesday, December 24, 2003 10:45 PM > Subject: RE: [Leica] Fw: looking for line pairs with a stabiliser and a > Leica and question > > > > And, just out of curiosity, this has what to do with photography or > > any real world use of Leica equipment? Just wondering. ;-) > > > > -----Original Message----- > > From: owner-leica-users@mejac.palo-alto.ca.us > > [mailto:owner-leica-users@mejac.palo-alto.ca.us] On Behalf Of animal > > Sent: Wednesday, December 24, 2003 3:58 PM > > To: leica-users@mejac.palo-alto.ca.us > > Subject: [Leica] Fw: looking for line pairs with a stabiliser and a > > Leica and question > > > > > > Sorry for the earlier empty post. > > Here goes. > > A collegue and myself wanted to find out if we could get 80 line pairs > > > per millimeter using a Leica and a Kenyon gyro stabiliser. We could > > not find those data in literature so last night, while also doing a > > test of Laphroig versus Lagavullin, we decided to give it a try > > ourselves. > > > > We scribbled some lines on a piece of paper with a group of line pairs > > > one 1 cm per pair and the other 5 mm per pair. With a Noctilux 18 > > meters away we calculated the image on the film to be 36 and 72 line > > pairs per millimeter. We suspended the camera and running gyro from a > > bungee cord and started. First exposure was at 1/250 second and f1.0 > > going in stops to 1 second and f16.0. > > > > Then we tried the same sequence while handholding the camera and > > bracing ourselves in a doorway. > > > > By then we became to doubt the ability of a 4000 dpi scanner to > > resolve our results. While one would assume that 4000 dpi translates > > to 80 line pairs per millimeter,some knowledgeable people we asked > > suggested that 60lp/mm is about the best such a scanner can do. So we > > had to aim a little lower and did the same test with an aasummicron90 > > mm and the stabiliser starting at 1/60 and f2.0 . > > > > Although our test was hastily done it still yielded some suprises to > > us. The biggest being that the stabiliser clearly is able to permit > > shots at 1 second. Others were that the noctilux was still giving good > > > results at f 4.0 and 5.6 and stayed that way until f16.(we realise > > that the focus shift of the lens could have been to our advantage at > > those apertures if we started out with a focus error). Also suprising > > was that at f 8.0 and smaller the summicron image is starting to fade. > > > Lastly it shows that it is hard to find the testcard when handholding > > the camera. On the page the first column is the stabilised noctilux > > the second is the same handheld(stopping at 1/8th) and the last is the > > > summicron. The film used was Kodak E100 GX . The question is to get > > rid of focusing errors .can one set the lens accurately at infinity > > just by putting the index on thatmarkingAnd if so at what distance > > would one have to put the target? > > http://www.leica-gallery.net/apekop/folder-6004.html > > best regards > > simon jessurun > > > > -- > > To unsubscribe, see > > http://mejac.palo-alto.ca.us/leica-users/unsub.html > > > > -- > > To unsubscribe, see > > http://mejac.palo-alto.ca.us/leica-users/unsub.html > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html > > -- > To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html > - -- To unsubscribe, see http://mejac.palo-alto.ca.us/leica-users/unsub.html