Bokeh Panorama Science - Perspective
To some the benefits of shooting a Bokeh Pano will be obvious. The main purpose is to have a wide angle view with a shallow depth of field. You also get a massive resolution (for the little bit that's in focus), but in this post I want to focus on the perspective benefits of getting closer to your subject and shooting more images.
To illustrate: I took this single photo of a bike with an 85mm lens. The camera was about 10m away from the subject here and the lens was at f/1.2 (all of the following shots will be at this aperture).
This next image is a panorama, stitched from about 8 images and was focused at around 5m. This represents roughly a 60mm lens (f/0.85 equivalent).
This next one is stitched from about 30 images, focused at around 2m. This represents roughly a 33mm lens (f/0.46 equivalent).
Judging the delicate interplay between the perspective effect of your subject vs the background detail (plus how blurred it is) can be hard when also considering the focal distance and only seeing a fraction of the final image. For this reason I highly recommend using a separate viewfinder to help visualize your final composition. Although this won't display your desired depth of field it will help with the most important factor.
Another observation that I made here was that the amount of blur seems higher the wider the shot gets. Getting closer to your subject compresses the depth of field, think macro, (illustrated above), but this is counteracted by zooming out when going wider to frame the same subject. Although these elements are cancelling each other out to some degree it's ultimately the bokeh effect that wins and this I didn't quite expect.
This final image (with processing) is equivalent to a 24mm f/0.34 lens, or an effective sensor of 120x80mm.
In my early attempts with this technique I struggled to get the extreme effect due to concentrating on going wide, rather than getting close (and going wide). My advise here is to think about the final image and not worry about only fitting small details into each frame.
You can see more of my Bokeh Panoramas here.