Forum : Advice & Critiques

Can’t seem to get something to synth right? Curious about what lens is best? Ask your fellow Photosynthers here.


Topic: old postcards

Report Abuse Report Abuse
lowtone (Over 1 year ago)
Hello. I wanted to use photosynth in order to get a 3D view of destroyed buildings that only survives on old postcards. There is no possibility to make new pictures anymore. So i've tried to get as many old pictures as possible, but they never synth. Why? and what to do?
thanks
NateLawrence (Over 1 year ago)
Hello, lowtone, 

I'm sorry to hear that you're not having more success. 

Photosynth's ability to automatically match photos is good, but there are still limitations. It still is nowhere near as good as the human brain at recognizing the same things from different angles or dramatically different sizes within the frame of the photo. 

I took a quick look at your profile and I think that you are probably talking about these two synths: 
tr2: http://photosynth.net/view.aspx?cid=f7d45a72-5484-4bc7-9be7-a3fa5a1cdda0
3: http://photosynth.net/view.aspx?cid=912c0c62-e653-4020-acb4-ae16603a698c
NateLawrence (Over 1 year ago)
In both cases (both the full photos in the first synth and the cropped versions in the second) you do have several shots from the front of the building which are from similar enough angles that they ought to match. 

The aerial shots are from much too different an angle and you need some intermediate angles for those to match. 

Both synths also suffer from the input images being quite low resolution. This means that Photosynth does not have sufficient detail to analyze, which is likely the reason why the shots from the front views are not matching. 

Are these postcard images which you have scanned with your own scanner or only images that you found online? If it is possible, try to make maximum quality scans of the original postcards. Even then, some of the angles may not be close enough to each other to match, but that would give you much better odds of success.
NateLawrence (Over 1 year ago)
Photosynth's image matching limitations are described in more detail in the Photosynth Photography Guide, available from this Help page in several languages: 
http://photosynth.net/help.aspx#photosynthhelp
lowtone (Over 1 year ago)
Thanks for your answer.
I've tried once on another building with internet pictures, real postcards, and newspaper pictures but it was not sucessful too.
Here i only have internet pictures in poor quality. I've tried to remove stamps and texts from the pictures. Maybe i should buy real postcards at thrith store.
If i go to Paris i could not make picture, the place is not the same anymore http://parisavant.com/index.php?showimage=199 . The theatre room and the towers have been destroyed, and the new building has been build over the remainings.
The problem with aerial shots is that they seems to be very rare.
Last year i tried to make another synth with this building
http://indre1418.canalblog.com/Chateauroux_Theatre.jpg
It fails. So i was thinking, why not make a cube in paper and project the postcards on it, and take pictures to have all the angles to match? Maybe my idea is silly. I've never tried yet. The place is too different today to make new pictures…
You need to be Signed In to add a comment. (Are you new? Sign Up for a free account.)