Big Ben's Panorama Tutorials

Lenses

Which lenses work with this method?

All lenses will work with this method. You'll just need a lot more images to complete the sphere with longer focal lengths. The first part of the method is also useful for stitching cylindrical panoramas together, but then it's also pretty much the same as other tutorials on PT Tools for this.

For 'complete' panoramas though you can still use a wide range of lenses. It can (and has) been done with 'ordinary' lenses. The fewer the images you have, the fewer the control points you need, the fewer the stitches you have to prepare and, obviously, the quicker it takes. My personal preference would be at least a lens that enables you to shoot one horizontal strip of images and one vertical image to patch in the remaining gap. For that you're looking at a full frame fisheye. Circular image fisheyes can in theory create complete panoramas with just two images however I have found it easier to get very high quality images using a horizontal row and vertical patches as well.

Full Frame Fisheyes: Rectilinear of Plain Jane

One of the greatest features of Panorama Tools is that it is capable of correcting virtually all lens distortion. This makes the question of distortion irrelevant then, which brings to the other requirements of a lens.  The other two things you need to look for are light fall off toward the edges and edge to edge sharpness.  While Panorama Tools will compensate for light fall off from the centre of the image this will not necessarily correct all colour/contrast variation that can occur. Practically all lenses will have light fall off towards the edges because they are stretching the image more at the edges than at the centre of the image however this can be more pronounced in poorer quality lenses. Image sharpness is perhaps the most critical quality of a lens for panoramas though.  Try before you buy and check the sharpness at the edge of the image.

Circular Fisheyes

Circular fisheye images are, well, circular and represent a view of around 180. Unlike all other lenses though there is no attempt to stretch the image to reduce distortion. This means that there is (practically) no light fall off towards the edges of the image. This makes stitching SO much easier. With only 3 horizontal images required for a panorama it is also much easier/faster to shoot a panorama and with 180 filed of view it is also easier to deal with lens flare from the sun and other bright lights (more later).

Autofocus or Manual Focus

If you believe the sales pitch they will tell you that there is practically no difference in image quality between manual and autofocus lenses. And yet when I look at the specs for my manual focus lens it has a much different configuration of elements from its autofocus counter part. And autofocus on an 8mm lens??  You could make a fixed focus 8mm lens with a rotating focus collar that did nothing and most people wouldn't notice. The focusing mechanisms of autofocus lenses are of necessity very sloppy. I don't like that, and after a lot of persistence I finally managed to get the importer to a) recognise the existence of a manual focus version of my lens (you know, the one in the brochure and on their website?) and b) actually order it. 


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This page, its contents and style, are the responsibility of the author and do not represent the views, policies or opinions of The University of Melbourne. All photographs Ben Kreunen 2000

Ben Kreunen <bernardk@unimelb.edu.au>
Department of Pathology
Last modified: February 24, 2003