I'm expecting to use similar sized files for surface images. I have an area of interest about 10km x 10km and I have a 140 MB tiff of the aerial photograph (of a larger area). Not yet tried it with Therion. I'd expect to downsize the tiff somewhat, but I think it is inevitable that the file will be large to get a reasonable result. I agree that for most other uses there is no need for images larger than a few hundred kB. Bruce -----Original Message----- From: therion-bounces@speleo.sk [mailto:therion-bounces@speleo.sk] On Behalf Of Martin Sluka Sent: Monday, 13 July 2009 4:36 a.m. To: List for Therion users Subject: Re: [Therion] Size of image files On 12.7.2009, at 17:38, Graham Mullan wrote:

Importing a 20Mb png image

Is there any reason to use such a huge background images? 100 dpi and couple of scraps (about 100 m of passages) should be enough. Similar for surface. Martin

2009/7/13 Martin Sluka <martinsluka@mac.com>:

There is a limit of altitude points Loch is able to work with. And there is no sense to have more pixels than altitude points.

Surely the view creates a mesh over the altitude points you give, and you want a higher resolution bitmap for the overlay than the number of points in the mesh?