You really need to know a couple of things, the more or less exact location from which the image was captured, exactly what the format of the image was, (which should relatively easy if you have an uncut original since prints were usually contact printed), but your assumption is wrong on focal length. Most likely if the traditional definition of normal is used, then the diagonal of the film = normal focal length. So on 35mm film you need a ~43mm focal, on APS-C you need a ~28mm focal length, etc. Of course that rule was sometimes broken by manufactures, (for example a lot of US manufactured TLRs had longer than "normal" focal lengths to improve edge sharpness, though they were built much later than this photograph). As it was taken by a "professional" with a view or field camera and he probably coated his own plates and he may have used any lens he available.
Lasse Karlsson wrote: > Hi all, > > I'm doing some research on the earliest constructions of my hometown, > Mariehamn. > > At the link below there is one very early photograph of the town, from > around 1870. In it there are still a number of houses, farms, of the village > where the town was founded in 1861. I'm trying to establish the exact > location of these constructions, so that I can draw them on a current map or > walk there and say: This is the south-west corner of that house, this is... > etc.. > > (The photograph, originally in B&W, is a "working copy" of mine, where I've > added a few things in color just to help me see various parts more clearly.) > > The constructions which I'm interested in, are to the left, on the hill, as > well as on the slope towards the photographer. > > I know, or will be able to pin down the exact locations of some houses, or > corners thereof. Some of these have been marked with a blue "x". > > Now, I believe that it should be possible, to actually determine the exact > locations of these buildings just by going by this photograph. (Let's say it > was shot with a lens equalling 50mm on 35mm film camera.) > > Am I correct or mistaken? > > If it's possible, can anybody help me out in how to go about doing it, or do > I have to redo my geometry classes? > > http://photo.net/photodb/photo?photo_id=6894839&size=lg > > > Thanks for your comments, > Lasse. > > > -- I am personally a member of the Cream of the Illuminati. A union with the Bavarian Illuminati is contemplated. When it is complete the Bavarian Cream Illuminati will rule the world -- Anonymous -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
