Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Igor Roshchin
Bob W. wrote: > So what? During the Renaissance and later some painters used optical > devices, lenses etc. to help them with their painting. We know this > because some of them, and some other Renaissance people, wrote about > it and even painted it. It was no secret. Bob, chill off, take a de

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Paul Sorenson
hen. > > -- > Bob > > >> -Original Message- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On >> Behalf Of Lasse Karlsson >> Sent: 30 January 2008 09:37 >> To: Pentax-Discuss Mail List >> Subject: For the experts. Determening distances in a p

RE: For the experts. Determening distances in a photograph.

2008-01-30 Thread Bob W
> > > > Actually, this maybe of interest to some people on this list. > > > Charlie falco who is a physicist, together with an artist > > > David Hockney > > > did a research where they used optical distortions to demonstrate > > > that some Renaissance era drawing were made by tracing images > >

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Igor Roshchin
Wed Jan 30 16:27:24 EST 2008 Bob W wrote: > > Actually, this maybe of interest to some people on this list. > > Charlie falco who is a physicist, together with an artist > > David Hockney > > did a research where they used optical distortions to demonstrate > > that some Renaissance era drawing

RE: For the experts. Determening distances in a photograph.

2008-01-30 Thread Bob W
IL PROTECTED] On > Behalf Of Lasse Karlsson > Sent: 30 January 2008 09:37 > To: Pentax-Discuss Mail List > Subject: For the experts. Determening distances in a photograph. > > Hi all, > > I'm doing some research on the earliest constructions of my hometown, > Mariehamn

RE: For the experts. Determening distances in a photograph.

2008-01-30 Thread Bob W
ey and others make such a fuss about it. -- Bob > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On > Behalf Of Igor Roshchin > Sent: 30 January 2008 19:00 > To: PDML@pdml.net > Subject: Re: For the experts. Determening distances in a photogra

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Vic Mortelmans
Small addition: if you would attempt this, the direction of your camera *will* matter to get the correct perspective match with the old picture. The center of the old picture should be the same as the center of the new picture! Groeten, Vic Vic Mortelmans wrote: > If you could pin down the e

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread P. J. Alling
I just checked it's -15° -30°F if you take wind chill into account... Paul Sorenson wrote: > Where the current temperature is -16°F > > > >> Rick Womer wrote: >> >> > > He's in Fargo, ND, poor bastard! > >> >> > > > -- I am personally a member of the Cream of the Illuminat

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Igor Roshchin
Yep, that's obvious. The authors go much further than that. Take a look at the first two articles - it is rather interesting. (You can skip the math if it bothers you ;-) ). Also, a brief (and rather dry) summary is available on Wikipedia: http://en.wikipedia.org/wiki/Hockney-Falco_thesis Igor

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread P. J. Alling
The original camera was a darkened room with a lens and an artist drawing on the wall opposite the lens. Camera does mean chamber, as in room, in Latin. Igor Roshchin wrote: > Lasse, > > Yes, your problem may be solvable. > Sorry, I wouldn't have time and energy now to help you solving your > pr

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Paul Sorenson
Where the current temperature is -16°F > Rick Womer wrote: > > He's in Fargo, ND, poor bastard! > > > -- 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 direction

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Igor Roshchin
Lasse, Yes, your problem may be solvable. Sorry, I wouldn't have time and energy now to help you solving your problem now. However, you may want to take a look at the articles posted on Charles Falco's website (in the "scientific papers" area): http://www.optics.arizona.edu/ssd/FAQ.html While a

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Mark Roberts
Rick Womer wrote: >Maybe a surveyor would know. Dave Brooks, are you >there? Dave's not here! He's in Fargo, ND, poor bastard! -- 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

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Rick Womer
Maybe a surveyor would know. Dave Brooks, are you there? --- Lasse Karlsson <[EMAIL PROTECTED]> 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.

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Rick Womer
Maybe a surveyor would know. Dave Brooks, are you there? --- Lasse Karlsson <[EMAIL PROTECTED]> 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.

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread P. J. Alling
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

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Vic Mortelmans
Or you could maybe try to overlay it with a grid in the same perspective as the scene. I tried something like this: http://users.pandora.be/vicmortelmans/tmp/6894839-lg.jpg But I don't think the perspective is correct... Groeten, Vic Lasse Karlsson wrote: > Hi all, > > I'm doing some research

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Vic Mortelmans
If you could pin down the exact location where the photographer was taking this picture, you could take a new picture of the current situation, and by layering the old picture on the new, you can at least find out where the old buildings were as compared to the current situation. I don't think

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread Paul Stenquist
Are some of the buildings still standing? If so, I would measure one existing building that appears in the rear of the photo and one in the front. That would give you a scale and a perspective ratio. Someone else may have a better idea. Paul On Jan 30, 2008, at 4:37 AM, Lasse Karlsson wrote:

Re: For the experts. Determening distances in a photograph.

2008-01-30 Thread mike wilson
ot; <[EMAIL PROTECTED]> > Date: 2008/01/30 Wed AM 09:37:20 GMT > To: "Pentax-Discuss Mail List" > Subject: For the experts. Determening distances in a photograph. > > Hi all, > > I'm doing some research on the earliest constructions of my hometow

For the experts. Determening distances in a photograph.

2008-01-30 Thread Lasse Karlsson
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 establi