Now that I finally own a full-frame DSLR, I wonder if I should buy a lens with a 15-mm or 16-mm focal length. My current zoom can go as wide as 24 mm, which seems like an ultra wide-angle effect to my eye, but is it wide enough?
Well, Paul, a lens needs to have a focal length shorter than 24 mm to be classified as an ultra wide on a full-frame DSLR. While your 24-mm lens does produce a very wide angle of view, shooting at 15 mm or 16 mm can enable you to make super wide-angle images. While travelling in Europe recently, I often used a lens of this type and really appreciated the ability to include much of the interior of a large church or castle in a single frame. Occasionally, I also found the short focal length useful for other types of urban photography and for landscapes.
Granted, the shorter focal lengths do tend to increase the risk of “distorted” perspective as discussed in the previous Q&A “I bought an ultra wide-angle lens and the distortion in my photo is terrible.” However, tilt the lens quite steeply to make your creative intentions obvious to the viewer, and the results can be quite dynamic. For indoor architectural scenes, strive for great symmetry for the most satisfying effect with a super wide lens. In other words, make sure that you position the camera perfectly centred to the scene and that it’s not tilted to the left or right. If necessary, do some slight cropping in software to ensure that the image is perfectly centred.
Not every owner of a full-frame DSLR will appreciate super wide angle effects. If you’re not sure as to whether this would be a wise investment, consider renting a suitable lens for a few days and use it often. You should have no problem finding a Zeiss 15-mm f/2.8, a Canon 16-35 mm f/2.8 or a Nikon 16-35 mm f/4 model for a DSLR or a Sony 16-35 mm f/4 for a full-frame mirrorless Alpha camera. As a starting place, check out the firms discussed in the previous Q&A “Can you recommend lens-rental companies in Canada?“