Not far from the Quad Cities, in Illinois, there is a very nice community called New Windsor. While New Windsor is famous in our area as the host of the “Biggest Little Rodeo” … it should also be known as one of the nicest “country” church around. You don’t need directions to get to Calvary Lutheran as it is a very prominent landmark in New Windsor that would be difficult to miss. This is the church home to a few of my friends and colleagues and in particular Eric Young asked me to do a 360 Panorama of the sanctuary. Here’s my attempt.
I used a 35mm lens at f16 on my iDmkIV for this pano and therefore took 75 frames to stitch together. I did 5 horizontal rows of 25 frames each with a Nodal Ninja 5 pano head. Church sanctuaries, in particular, have a lot of dynamic range to them with some dark shadowy areas and some brightly lit highlight areas. This one was no exception, and was particularly challenging since it was a bright, clear day and the morning sun was shining directly in the stained glass windows over the entry doors. Therefore I used HDR processing to accommodate this high dynamic range scene and used 7 exposures of each frame with a 2eV step between each exposure to capture a 12eV total range. As a result, I ended up with 525 separate images to process into this single panorama.
The image you see above is the flattened “sphere” that results from the stitching and HDR operations. I use a software product called PTGui, which uses the Open Source Pano Tools project, to get this far. I am pretty proud of the quality of the stitching. While it took me a little white to hand tune the control points for the image, the result is pretty satisfying. I have yet to identify a stitching error.
The HDR part is a little more challenging and I continue to experiment with different HDR processors to improve the image to capture more of the detail in the windows. One of my challenges is that this image is pretty large, something like 37,000 x 12,000 pixels. It’s difficult to find good software tools that can handle these types of images. (The resulting photoshop file of the above image, including each of the 7 blend planes is something like 30GB is size).
So far I’ve tried true HDR Tone Mapping and Exposure Fusion with PTGui and then improve the image in Photoshop CS5. The above image was created with Exposure Fusion processing and is an improvement over the the HDR Tone Mapping I tried originally. I’ll update these as I go along.
Even though I am using a 4 core i7 processor with 12GB of memory, these images take days to process … literally.
While this is an interesting overview of the Panorama, the objective is to create a virtual environment that the user can navigate around and zoom in and out as they see fit. Therefore I use another set of tools called krpano to convert the above flattened sphere into 6 faces of a cube, these are then combined into a large set of multiple resolution files that use Flash for display on PC’s and HTML5 for display on mobile devices. You’ll be able to zoom in more on PC’s and Mac’s than you’ll be able to on mobile devices
I hope you enjoy this display of the Calvary Lutheran Church in New Windsor, IL.Tags: Panorama
