It took a while to build it though...
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I shot a set of hand-held digital photos from a pivotal point in the driveway—the seam intersection of the concrete slabs, near the drain grate—with my little Samsung 800K. Each image was 1024 x 768 pixels.
I needed to "stitch" these together so to form a continuous tube or ring panorama. I tried the recommended Panorama Factory application which, in general, was easy to use. It was described as free; ah, no—it's shareware! The downloaded version 4.1 appeared fully-functional but put a watermark in the middle of the image. OK in a huge panorama but very distracting when I tried 2x1 stitches. And I had begun these efforts in an attempt to stitch image files vertically.
I tried Pixtra OmniStitcher in hopes of vertically and horizontally stitching but found it incredible frustrating. Maddening. I investigated a number of other titles but found many crippled.
Finally, I tried HugIn 0.7 beta. Did the job. Fairly straight-forward. And free. It built a very large JPEG image file, 9020 x 3307 pixels!
Then next stage was to "blank out" the sky above the houses and trees. I tried to do this in the GIMP 2.2. I considered using a mask of some kind but I couldn't figure that out. So I ended up using the lasso button (Select hand-drawn regions) to manual select areas close to the sky. I filled these regions with a foreground colour (via the Edit menu), i.e. black. At some point I had added an alpha layer for transparency. I can't remember exactly how I did though. I'll have to review that critical step... The "magic wand" tool for Select Contiguous Regions was handy for little spots within trees! Finally, I saved the file in native GIMP format (XCF) to preserve the alpha transparency and layer information.
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEi7bKQIwfR1zoZBxF0qqfnwi_1fb3tdPPnX19kNKywVi6ChQI4ze9dqCoDWWIWnGZol78ofN5SA0g7WsAnn1KM91-PQ60BZMwQ-XXSOAB_R_hC9Ogm6PpWm4VFhAPWeTe1L-EBOKg/s400/wrap+around+2c.jpg)
Warning: Thumbnail linked to super-wide panorama image!
Now this is where I got into trouble!
After cropping and rescaling, I started to work from a panorama that was 9024 x 1992. I divided this horizontally into 8 images, each panel ended up 1128 x 1992 (I know, I know, not square). Saved each panel as a PNG file.
Loaded into a new folder. Stole a "floor" from another landscape. Re-purposed a landscape.ini file for my image files and location. And then spent some time tweaking the ini file to get a good look. Not bad for my first attempt. but the main problem was that some form of stretching or replication was happening between the panels. I assumed it was because of the aspect ratios on my files.
When I read on the Stellarium forums landscape page their "warning" that if you want to publish a custom landscape you have to use power multiples (e.g. 512, 1024, 2048...), I realised I needed to rework my images.
So, back to the (electronic) drawing board. After some aggressive cropping, I had a panorama 8192 x 1024. The problem with this size was that I cut off essentially everything at the 1 metre level and down. This also cut the very top edge of my house roof-line. Everything works, from the tree lines and up; but the ground looks very strange. Or that the back yard is filled with quicksand.
Second attempt: overall, impressive!
I don't know if in the end there is anything I can do about this... My situation is unusual verses the other Stellarium landscapes. They show wide open vistas. Something all astronomers want, obviously. But I'm a metre or two from a two-storey house which effectively blocks out 80° of the sky.
I fell asleep wondering if I could go to a 16384 x 2048 panorama. This might capture the peak of the house and a bit more of the ground... But it may require I start from scratch, shooting a new series of photos... Maybe I should use a different camera with a focal length shorter than 47mm.
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Appendix: Discoveries on Editing a Stellarium landscape.ini File.
As the parameters for multi-image handling within the landscape.ini file are not thoroughly documented in the Stellarium user guide, I thought I'd make some additional notes.
- The description parameter must be entered as one line. Do not insert hard line breaks during data entry; soft breaks with word-wrapping OK.
- Do not allow more than approx. 40 characters per line in the description. Use the \n switch (that's, backslash N, in lower-case) to form a line-feed within the landscape dialog box.
- The side0 (i.e. side zero) panel starts at the east cardinal direction. I.e. the left edge of the panel is aligned due east. Panels continue clock-wise. In an 8 panel multi-image display, side6 will correspond to north.
- The decor_alt_angle parameter affects the vertical angular size of the panels, i.e. shortens or elongates them. Acceptable value ranges from 1 to 90 degrees.
- The ground_angle_shift parameter affects where the "floor" image is placed in relation to the "camera," i.e. in elevation. If you use a positive value, your perspective will be from below the floor image.
- Minor changes to the landscape.ini file may be tested rapidly, after saving, as Stellarium runs, by switching "away" from the custom landscape and then immediately switching back to it.
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