Vertical Panorama tests

This is a vertical panorama inside the Cathedral Saint Marie here in  Auch

It is made up of 30 individual images. The ‘wobbly’ effect (look at the columns) is caused by a problem of parallax which I hope to be able to reduce as my testing proceeds.

How it was done : the camera was fitted with a very wide angle lens, in this case 14mm, and sat on a tripod. Initially the camera was horizontal and 5 images were made – two underexposed, one correctly exposed and two overexposed, without moving the camera.

Then the camera was tilted up 7,5 degrees and 5 more images made.

This was repeated to create 6 groups of 5 images, with the camera travelling from horizontal to vertical.

In post processing, each group of 5 images shot in the same position was ‘summed’ together – this creates an HDR (High Dynamic Range) image which allows data from the deepest shadows to the brightest light areas to be added together to increase the dynamic range of the resulting image. (Remember, -2, -1, normal exposure, +1, +2)

Finally, the 6 HDR files were then ‘stiched’ together vertically to create this vertical panorama.

I will eventually be able to correct the parallax * problems, but for this first phase of tests, I’m not unhappy with the results.

*Parallax – if the nodal point of the lens is not centered about the pivot point of the tripod, or point about which the camera turns, then there will be an effect of ‘parallax’ which will change the relative position of the elements in the image. This can be overcome be moving the camera/lens backwards of forwards across the mounting plate on the tripod. To do this successfully I need a ‘nodal slide’ – it’s been ordered and is on it’s way…

When it arrives I’ll continue my testing…

Credit Really Right Stuff