Aperture is warning you that the pixels-per-inch are not high enough to produce an acceptably sharp print.
Badges are explained here in the User Manual.
You can either:
- make the print area smaller
- print as is
I don't know the number Aperture uses as a cut-off, but a quick test shows it's 150 PPI. Afaik, this number is fixed; it is not relative to printer, content, or anything else.
What units are you using for "297 x 900"?
150 pixels per inch is equal to 6.1 pixels per millimeter. You need 1812 x 5490 pixels to print 297 x 900 mm at 6.1 pixels per millimeter. Aperture is telling you that your Image has fewer than that.
Note that 150 PPI is a good minimum to work with. You really want at least 200 PPI, and closer to 300 PPI, for "sharp enough to be examined by hand" prints.
how do i go about that
Go about what?
To have enough pixels to print large sharp prints, you need to record them. Since you are stitching panoramas, things you might consider:
- make sure your stitching program is giving you back almost as many pixels as you put in
- record more pictures to stitch together, each of which covers a smaller arc of the scene
- use a camera that records more pixels.
What size are the panoramas you've taken? Are the ones that don't show the yellow warning badge larger than those that do?
What does Panasonic say about the size of panoramas recorded with your camera?
My guess is that at almost 1 m wide you are at the limit of how large you can print at 150 PPI due to the limitation in how many pixels you can record in panorama mode.