As far as I recall, there is no size limit in Qimage, only your driver.
Set the paper to roll paper and BANNER mode, and the length to whatever you want.
You can also use CUSTOM and insert the long side and let Qimage figure out the rest.
Hope this helps
Fred

There is no limit to "remove" because the limit is defined by a 32 bit application which Windows only gives about 2GB of RAM to work with.  That 2GB of RAM will allow processing of images up to about 1GB (about 300 megapixels).  To go beyond that, Qimage has to be rewritten as a 64 bit application and I'm currently working on that but don't expect to see a 64 bit version before the end of this year.

As it stands, 300 megapixels is enough to handle a pano of about a dozen stitched 24MP images.  That's a final image of about 21,000 x 14,000 pixels which is good for a size of 70 x 47 inches in print size.

Your Epson P800 is not a very wide format printer at 17 inches.  If you are printing 17 inch tall panos, you can print a 200 inch wide pano before you hit that 1GB limit of image size if you create your pano at 300 PPI!  If you are running into trouble printing any reasonable size pano on a P800, you are likely going way overkill on the resolution: keep your resolution of your image at 300 PPI and you'll have no problem with the current version of Qimage!

Regards,
Mike