Finder
Veteran
sjw617 said:
Stand in front of a brick wall and look straight at it. The bricks infront of you look parallel. Look to the left by about 45 degrees, and you see the bricks converge and are smaller. This convergence is proportional to the angle and is related to how far the object (bricks) are away from you. I don't think you are going to argue that bricks at x ft. appear the same size at 2x ft. So the "cigar projection" is actually correct and supports my statement.
The flat film plane of a panoramic camera has increasing magnification that compensates for the decreasing image size of the bricks from the optical axis. While this is easier for your mind to relate to, it is still an illusion as it is trying to eliminate perspective.
Now print viewing also plays a part in this and so it is not so simple. If you curve the swing lens image at the same relative curvature as the film and place your eye at the foci, you will see the scene exactly how it was in real life - perspectively speaking. You can do the same with the flat plane camera by viewing it at the optical axis at a relative viewing distance as the focal length of the taking lens (A image taken with a 50mm and enlarged 2x should be viewed at 100mm). This will also show that the wide-angle effect is not distortion as objects will not appear stretched at that viewing distance at the optical axis. Both methods tend to be distorted because they are never viewed "correctly." But a swing lens camera is far from a distorted view.
BTW, if by "stretching" you are refering to the wide-angle effect. This is a problem with flat plane cameras. Spherical objects (3-D) at the edge of the frame like heads or light blubs appears stretched away from the optical axis. That is a problem of projecting 3-D objects off-axis on a flat film plane. I am sure you have seen this with your 6x17 camera. The stretching is not an actual distortion as it is not seen at the "CORRECT" viewing distance and position - unlike a fisheye, which does distort the image through barrel distortion.
sjw617
Panoramist
Ahhh... now I understand what you mean. I rarely encounter that problem with the 617 because I mainly shoot landscapes. BUT I am going to go to the archives and look for some examples.
Finder
Veteran
The wide-angle effect is there, but it can be hidden. This image was done on 6x12 with a 55mm APO Grandagon. Look at the head in the bottom left corner of the frame a you may notice a stretching away from the optical axis - the heads on the other side show it at well, but not as obvious. Be careful, like vignetting, once you learn to spot it, you will be seeing it in every image. 
