London, Feb 2012 – Peter Marshall – see text
This isn’t by any means a perfect panorama*, though I’ve just spent over an hour trying to put it in order. There are still few fairly obvious problems, and though with perhaps another half hours work I could eliminate most of them by appropriate masking of the images, I decided I’d done enough for what is only really a preparatory sketch, make when I just happened to have a spare few minutes in a location I’d been meaning to visit as part of a joint project with an artist friend I’ve been working on for some time.
I hadn’t gone out to take panoramas, and didn’t have a tripod with me, and it isn’t easy to keep a hand-held camera in the same position over the 13 frames that made up this 360 degree image. So it isn’t possible to get quite everything joining perfectly, as you can see in the jump in the yellow line at the right of the image around a quarter of the way up the frame and the sweep of the steps at bottom centre.
There are also problems with the various people who walked through the area while I was making the set of exposures. Some of them were recorded several times in different frames, and I wanted to avoid showing them more than once in the final image. More annoyingly, there were different people occupying the same space in different frames, and I had to choose between the woman clutching her blue folder and a man with a banana, whose image I obliterated.
There was also a problem with changing lighting, with the sun disappearing behind small clouds as I took the pictures. The main problems this gave me were in some sky areas, where white clouds rather dramatically darkened. There is also an interesting lighting effect here with strong reflections from the ‘Gherkin’ at centre right giving one man a strong visible shadow although like the rest of the figures in the scene he is actually in the shade, and the shadow is pointing in the direction of the sun.
I seldom find 360 degree panoramas very interesting as prints, although it’s often interesting to explore them through a small viewing window on-line. This square on St Mary Axe known to Londoners as ‘Simmery Axe’ (that church was demolished in 1561) in the business district opposite Lloyds is surrounded by tall modern buildings (and the cranes where another is being added) along with some older architecture, notably St Andrew Undershaft. Until recently a maypole (the ‘shaft’) was kept horizontally on hooks on the side of one of the now-demolished buildings. The original maypole was taken down in 1517 after violent May Day rioting by London’s apprentices in which several foreigners were killed and was sawn into pieces around 30 years later after an inflammatory sermon against the excesses of May Day preached at St Paul’s. It was replaced st the Restoration in 1660 and finally taken down in 1717. Although the maypole was said in medieval times to tower above the surrounding buildings, it would look rather smaller now.
Working in the middle of large buildings such as those around the square needs a very wide view to encompass the tops of them all, but with a very wide view – particularly 360 degrees – it is then difficult to give a real impression of height. Working with a very large vertical angle also gives huge problems with distortion when producing flat prints. Some of the possible projections for smaller angles of view become unusable. For this image I chose an equi-rectangular projection, which works fairly well but used ‘neat’ seems to rather squash the taller buildings. A variable slider in PtGui (the best panorama stitching software) allows you to stretch everything out a bit.
Lightroom added to my problems by forgetting the profile setting that I had saved for the Nikkon AF DX Fisheye-Nikkor 10.5mm lens. For some unknown reason the default profile that comes with it attempts to convert the images to rectilinear perspective – which really doesn’t work, at least not without considerable cropping, as there are simply not enough pixels in the corners when the image is straightened out. It’s best not to remove the distortion at all, or at most around 20-30%, or to use other software such as my favourite Fisheye-Hemi plugin or other ways to convert to a cylindrical perspective. For working with PtGui, it’s pretty well essential to leave the images without conversion. So my first step this morning was to go back to Lightroom and rework the source images for the panorama.
With a proper rig for taking panoramas I think the 10.5mm should be able to create a spherical panorama with only six images, but working hand-held you need more even if you are satisfied – as I am – with a relatively narrow strip image. Thirteen is far more than needed, but I wanted to be sure not to get any gaps in the strip I wanted. But there may be some I could eliminate completely and get more accurate joins.
I made around half a dozen test panoramas while I was there, and I think my final picture if I decide to make one will be rather less than 360 degrees. Perhaps more like this one.
Stitched from many exposures with the 16-35mm rectilinear lens at 16mm
or even this
Stitched from two exposures with the 10.5mm semi-fisheye
*
A decent browser will display this image twice the size – right click and select ‘View Image’
________________________________________________________
My London Diary : Buildings of London : River Lea/Lee Valley : London’s Industrial Heritage
All photographs on this and my other sites, unless otherwise stated are by Peter Marshall and are available for reproduction or can be bought as prints.
To order prints or reproduce images
________________________________________________________