I think some people might have Norder3 and Norder5 from the dropbox at the beginning of the thread, and many won't want Norder6 and Norder7 because they are too much data for their needs. So I thought Norder1-4 (it's small enough anyway), Norder 5 (bit bigger), Norder6 (large), Norder7 (very large).
I don't think we can selectively choose which parts of a torrent we can choose to download? Correct me if I've made a mistake. Perhaps you can, and I can just create a torrent to my /usr/share/kstars/HIPS and people can choose what files to get?
We can selectively skip and give priority to files within a torrent.
I'm going to grab nordrer 1-4 and see if it's possible to reduce the image data with indexed colours. Report back later.
Edit: Nope, can't use indexed colours.
INDI/KStars on Raspberry Pi 4, 4gb
Raspbian Buster with AstroPi3 script configuration
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG/ASI120mm @280mm Guide Scope
Waveshare Stepper Motor Board - DIY Focuser
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
If I am not mistaken, this is possible: if for example you create a folder HIPS and then subfolders Norder1, Norder2 etc, then the user can select those subfolders individually through the torrent client.
But to be honest, I do not think that there is any need to do that now, it works greats just like you 've done it (thank you for that again!)
I found the following Table online in this document (page 11): www.ivoa.net/documents/HiPS/20170406/PR-HIPS-1.0-20170406.pdf
First item is the Norder, second is the number of files (or tiles), third item is the angular size of each tile, fourth item is the angular size of each pixel in each tile.
So for example, if you are wishing to use the HiPS for framing, this tells you that Norder5 provides you with 12.88 arc seconds per pixel, which each tile being 1.832 degrees across.
Norder7 has each tile 27.48 arc minutes across, with a pixel size of 3.221 arc seconds.
FYI, Norder8 would be around 78GB in size, with a pixel size of 1.61 arc seconds (it appears to halve as you raise the HiPS order by 1)