Thanks. I will try Osmconvert. (That is idiotic - I was on the geofabrik website and downloaded the Canada OSM, but did not realize Canada had sub-regions. Logically, BC and Maine would be at the same level.)

Thanks for all the comments. This is annoying me now; I thought it would be simple - just record some tracks and plot them. But usually I’m on a motorbike on a logging road, and 100m accuracy is often good enough.

Strava if I understand it relies on many different track uploads, and treats them all equally. Not so helpful here without a lot of volunteers. I can’t get around here on a bicycle, let alone a motorcycle in reasonable time - a couple of trails have sections with a fixed rope… (Well, OK, there is an adjacent area with a trials motorcycle course, but those guys are crazy and I don’t have one right now to map that).

I went and ordered a second GLO to play with anyway, before reading all the comments. I had been to a Trimble technical presentation talking about post-processing for DGPS, but that was years ago when SA was still in force. I’m not sure how to get raw data, or even log satellite data, from the GLO. I have maemo-mapper on my N810, and an Android tablet with Viewranger, but those just log regular GPX tracks with no HDOP. Anyone know any good Android bluetooth apps ?

Yes, I took some photos, but it’s hard for me to compare. I have the Squamish Select climber’s bible, which has lots of photos, so I need to go back, with the book, and positively identify the climbs while collecting and averaging GPS data. Hoping it doesn’t rain. The tops of some of the bluffs have a fairly good view of the sky.

The forest cover is I think coniferous, away from the wider trails which have some deciduous trees. I don’t suppose anyone would appreciate an “accidental” forest fire.

I’m not sure walking papers would be so helpful. The existing map is partly my fuzzy tracks away from the residential area, and there aren’t any good landmarks. The satellite photos show mostly trees.

Rangefinder - don’t have one (well, only an indoor one good for 50 feet). A survey crew would have some trouble - there isn’t line-of-sight anywhere and the trails aren’t straight.

Thanks guys. Turns out I had a note about tile URLs for Osma but hadn't loaded it in Maemo Mapper. http://tah.openstreetmap.org/Tiles/tile/%0d/%d/%d.png
OpenPisteMap also works, with the contours set as a layer
http://tiles.openpistemap.org/nocontours/%0d/%d/%d.png
http://tiles.openpistemap.org/contours-only/%0d/%d/%d.png

I tried pngout. Much slower than optipng, at least on the maybe 1.5Mpixel image I used.
I was thinking about bandwidth on mobile clients, not the server.

I remember I used to get significant reduction in GIFs by reducing the palette size, before everyone had broadband. With people getting images over cell data networks (and maybe paying per kb) there may be some point to it again.

On a related topic, I forget whether I saw it on OSM or Maemo Mapper - is there any scheme to save downloads by redirecting all requests for "empty blue tile" to the same URL ?

Ah. So if I edit a riverbank and break it and leave a hole, the sea will get in ?
I did fix some banks on the Fraser, but near Ladner, and I'm fairly certain I just added some points and corrected placement, not broke/split/deleted anything.