Re: [Leica] Q: Who's the lucky one ? (to Henning W)

[Bee Flowers <bflowers@cityline.ru>]

Henning, the mail I sent you came back "undeliverable", so I'll post it
instead.

Thank you for your kind comments. To answer your question re "how it's 
done", allow me to quote myself from another forum where a similar 
question was put to me. Here goes:

Those cubic (all around) panos have quite a learning curve, and I 
certainly claim no expert status, since some other people's QTVRs look a 
lot better than mine. But I'll be glad to share what little I know.


To get truly good quality, you would have to use a moderate wide angle 
lens and stitch scores of pictures to make a cubic qtvr. The use of a 
tripod is also essential to obtain the best possible quality. I have 
neither time nor patience to stitch tens of pictures for each pano, and 
in the case of my subway project, I also did not have the opportunity to 
use a tripod, for you'd have to be suicidal to set one up in the Moscow 
metro.


This then limited my options to handholding a camera with a 
non-equirectilinear fisheye lens. That's the sort that makes a circular 
image. I use a Nikon CP5000 with fisheye extender (I do have Leica 
cameras, which are the very finest of course, just like Leica people are 
the very finest netizens, but.... well... ). I set the camera to bracket 
3 exposures at plus/minus a whole stop. You must make sure that you 
don't move the camera while shooting off those frames for you'll need to 
superimpose them later on in Photoshop. After the first bracketed image, 
I turn 90 degrees, while taking a little step back so as to rotate 
around the lens' nodal point, not my own axis. This way I shoot in four 
directions (three would be enough, but I find it easier to 'guess' 90 
degs than 120 with little margin left for error).


In Photoshop, I take the brightest image as default, and copy/paste it 
onto a darker one, in order to erase through the brightest (now top) 
image with the (soft) eraser tool at 35%. This to fill in the burned out 
highlights.


When that's done, I use the (soft) dodge tool set to "medium/20%" with a 
radius of 300 and run it across the edges of the (round) image. This to 
  get rid of the slight vignetting that fisheye lenses have. The result 
I save with a simple title, such as "one", "two" etc.


The stitching is then done with Panotools. This is a truly unusable 
piece of software, unless you're a dyed-in-the-wool mathematician and 
programmer. People more like myself revert to the front end for 
Panotools, PTGUI (google for both!). Btw, this software will not stitch 
fisheye images unless you browse the internet for a 'restored' version 
of Panotools (some litigious company is giving the entire pano community 
a hard time, that's why). After you set a bundle of parameters and 
control points, your four (or three) images are stitched together. You 
should choose "photoshop with masks" as output option, because there's 
considerable work to be done in Photoshop to make the parts blend into 
each other nicely (in terms of brightness and contrast, that is). Out of 
Photoshop, you should save a flat file to a format of your preference.


But then: since I'm unhappy with how the the viewer that comes with 
Panotools shows large files (small ones work fine, but the big ones get 
really very shaky and slow), I use Panoweaver to convert the Photoshop 
file into a Quicktime VR. (Panoweaver is meant to make qtvr's out of two 
fisheye pics, but that just doesn't work: as a conversion program is a 
nice little thing, though). There are some other programs which can do 
this task just as well, though.


I can't quite recall, but it must have taken me weeks of fairly 
dedicated work to get decent results. Unless you're well versed in 
similar things already, there's a tremendous number of things that 
you'll need to learn; it's been a bumpy road for me. Having finally 
gotten the hang of it, I can now do one qtvr in under two hours at the 
computer.

Note that making a 360 degree panorama that does not need to be capable 
of functioning as a *cubic*, aka '360x180', QTVR is very very easy; with 
any of the multitude of available software packages it can be done in 
minutes. It's when you want your VR to have "straight up" and "straight 
down" capacity, that you're in trouble.

Bee




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